Course 1: Introduction to Water and Health Programme (Identical to Discussion Page)

Course 1

How to use the course materials:

The material is divided into Concept and Discussion sections. Most Concept pages are accompanied by a Discussion page. The Concept page gives a brief overview of the topic being considered and each Discussion page amplifies that overview into a more detailed review of the topic. The simple analogy is that the Concept pages are what you would see on a PowerPoint or blackboard summary in a lecture and the Discussion page is what the lecturer would say in class about that topic (or would provide in written lecture notes).

This means that you can use the Concept pages as a quick review of the topics by progressing through them in order using the Arrow icons at the top of the page (or in any order you want) and looking at the Discussion pages to amplify or remind you of the detailed content. This is very useful for a rapid review of course materials.

If you mark the level of understanding you have for each topic (from low to high - red to green) , you can then use these measures of understanding to review only those topics that you need to work on further or had difficulty with on first reading.

You may also add notes to any page or highlight materials for later study. For Help with the StudySpace software, see the Help Section on the left-hand menu. To see a PowerPoint Presentation on the StudySpace software used in these Water-Health courses see this link. PowerPoint or PowerPoint Viewer (free from Microsoft) is required and PowerPoint Viewer is included for installation from the CD

Any page may contain references to extra materials; either on the CD or as an external web reference (URL) (usually marked as Internet Access Required). You can access the CD material directly but you need an internet connection to access the external references. These extra materials and the external web references are NOT required reading but are there for those who wish to look at certain topics in more detail or who want to go to the original sources of material. The CD references are given to amplify the topics and are usually well worth reading even though we will not normally require any detailed knowledge of their contents for this course.

You will also see listings of material such as bibliographies and data sources on the internet. We provide these in an attempt to make the courses more useful to you in your career or studies, but knowledge of them is NOT required. They are there to provide reference materials that might be useful to you.

In short, everything you need to know for this series of courses is on the CD,, but you have been given extra materials and internet references to supplementary materials for clarification if

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c000TitlePage.html[11/3/2014 5:16:52 PM] Course 1

needed, for later use if it is relevant, or for you to pursue individual topics for your own interest.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c000TitlePage.html[11/3/2014 5:16:52 PM] Water and Health Title Page

Water and Health Programme Introduction

The Water and Health Programme consists of a number of individual courses addressing the many issues surrounding the relationships between water and the health of people and populations. This first introductory course will present an overview of;

Historical background to water and health Current and past issues in water and health The current global perspective on these issues Water Management overview - relationship to health issues A brief introduction to other parts of the Water-Health Programme

Other Courses in the Water-Health Programme are:

Course 2 - Water-related Impacts on Health - Principles, Methods and Applications

Course 3 - Technical Solutions for Water and Health

Course 4 - Water Ethics, Governance, Law, Economics and Social Intervention

Course 5 - Challenges for WaSH

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c001Introduction.html[11/3/2014 5:16:52 PM] Introduction - Overview

Historical background to water and health

This section will look at the historical background and the role of water and health issues in ancient and more recent civilizations

This overview will serve to put water and health issues into a much broader perspective and show how problems have occurred. what effects they have had and how solutions have been evolved over the millennia.

We will start with a very broad overview of the history of the Earth and the genesis and role of water in the first few billion years of Earth's history.

We will then look at the role of water and health issues on ancient civilizations starting around 10,000 BCE (Before Current Era) and continue until the present day.

After a brief look at the water cycle (the hydrologic cycle) we will examine the various uses for water and the global and regional use patterns

We will then look at global water issues and then at health issues related to water

We finish this first course with an brief overview of Integrated Water Resource Management (IWRM), one of the most commonly used management "systems" around the world that attempts to improve the overall management of water resources.

There is a list of resources at the end of this first course that will allow you to access data and information on water-related issues. Much of this information will be supplied but some is only available on the Internet.

You will also be given access to an on-line bibliography from UNU-INWEH (Internet Access Required) on Integrated Water Resource Management with more than 3000 searchable references on water-related issues (including water/health topics). This was prepared for the IWRM distance learning programme delivered through the Water Learning Centre (WLC) (Internet Access Required) ions.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c002Course1.html[11/3/2014 5:16:53 PM] Introduction - Water Supplies

Historical background to water and health Geologic Time Clock

All of the Earth’s evolution expressed as a clock with 12 hours! Notice that:

2. Eurkayotes emerged just over 2 billion years ago followed by multicellular organisms about 1.5 billion years ago

3. Land plants evolved at 450 million years ago allowing land animals to evolve

4. The first vertebrates occurred around 380 millions years ago and dinosaurs existed from 230 to file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c003EarlyHistory1Title.html[11/3/2014 5:16:53 PM] Introduction - Water Supplies

65 million years ago

5. First humans at 2 millions years ago (it almost doesn’t show on the clock!)

6. Modern recorded history and civilization only occupies the last 10,000 years (or less than the blink of an eye on the 12 hour clock!)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c003EarlyHistory1Title.html[11/3/2014 5:16:53 PM] Introduction - Water Supplies

Historical background to water and health Geologic Time Clock

All of the Earth’s evolution expressed as a clock with 12 hours! Notice that:

1. Photosynthesis started around 3.5 billion years ago and led eventually to an oxygen rich atmosphere about 2.3 billion years ago (see the outer purple line for “prokaryotes” that were responsible for photosynthesis) 2. Eurkayotes emerged just over 2 billion years ago followed by multicellular organisms about 1.5 billion years ago 3. Land plants evolved at 450 million years ago allowing land animals to evolve 4. The first vertebrates occurred around 380 millions years ago and dinosaurs existed from 230 to 65 million years ago 5. First humans at 2 millions years ago (it almost doesn’t show on the clock!) 6. Modern recorded history and civilization only occupies the last 10,000 years (or less than the blink of an eye on the 12 hour clock!)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c003History1.html[11/3/2014 5:16:53 PM] Where did the water come from

Where did the water come from?

Surprisingly, it is not certain how water came to be on the Earth. Some speculate that it could have come:

1. From the nebula dust cloud by the early Earth capturing hydrogen from the nebula that was subsequently oxidized to water through chemical reactions. This theory is somewhat at odds with the ratio of Deuterium to Hydrogen in water and the time scale required for it to occur seems to be too long.

2. From water contained in comets bombarding the early Earth (although their models show this could only have contributed about 10% of the water)

3. By the early Earth accreting water by bombardment with primitive very small planets and asteroids present in the outer asteroid belt. According to some calculations, this could account for sufficient water accumulation during the later stages of Earth's formation

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c005SourceofWater.html[11/3/2014 5:16:53 PM] Introduction - The Past

Historical background to water and health Early Human Evolution and Migrations

In East Africa near the Rift Valley, modern humans evolved about 200,000 years ago. The population rose and fell, and small subsets of the people left to go elsewhere, creating their own groups. Those groups spread, small subsets of the original groups leaving, sometimes returning and rejoining, sometimes leaving again. Africa has a huge range of environments—deserts, coastal regions, pampas, rivers, lakes, and mountains, and it is certain that some of these required human adaptations—behavioral, cultural and physical—to the demands of the various climates.

Eventually, we left Africa and colonized other parts of the world

As you examine these early migrations, consider the importance that access to water must have played; humans cannot go without water for more than 3 to 5 days so climatic conditions, lack of potable water and distances between water sources must have played a crucial role in these migrations.

On average, humans require about 2.5 litres of water per day to survive.

For a more detailed calculation of an individual's daily water requirement see the on-line calculator at http://www.csgnetwork.com/humanh2owater.html (Internet Access Required)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c008HumanMigration.html[11/3/2014 5:16:53 PM] Timeline of Ancient Civilization

Timeline of Ancient Civilizations

Timelines of Major Civilizations

Ancient civilizations usually established themselves near sources of water. Ample water quantity for drinking and other purposes was important to our ancestors, drinking water quality problems were not well known. Although historical records have long mentioned aesthetic problems (an unpleasant appearance, taste or smell) with regard to drinking water, it took thousands of years for people to recognize that their senses alone were not accurate judges of water quality. The three oldest civilization, the Indus, the Mesopotamian and the Egyptian civilizations were founded on water; all were on large river systems or flood plains (the Tigris-Euphrates in Mesopotamia, the Nile in Egypt and the Indus River in present-day India, Afghanistan and Pakistan). Before the major civilizations, there were periods that can be categorized as the Hunter-Gatherer and Agricultural societies. Then came Empires and, much more recently, European dominance. 1. Hunter-gatherer societies (up to about 10,000 years ago) 2. Agriculture (10,000 to 5,000 years ago) 3. Empires (5,000 to 1,000 years ago)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c010TimelineCivilization.html[11/3/2014 5:16:53 PM] Timeline of Ancient Civilization

4. European dominance (1,000 to 50 years ago) 5. The present day

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c010TimelineCivilization.html[11/3/2014 5:16:53 PM] Prehistoric and Hunter-Gatherer

Prehistoric and Hunter-Gatherer Societies

Stone Age: Paleolithic means "Old Stone Age," and begins with the first use of stone tools. The Paleolithic is the earliest period of the Stone Age. They lived as nomadic hunter-gatherers in most cases.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c040HunterGatherer.html[11/3/2014 5:16:54 PM] Agriculture

Agriculture

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c050Agriculture1.html[11/3/2014 5:16:54 PM] Agriculture

Agriculture Where did Agriculture begin?

Agricultural communities started in different places when conditions became suitable

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c060Agriculture2.html[11/3/2014 5:16:54 PM] Distribution of social and techn

Distribution of social and technological systems in early history Click on each map for a larger version in a new window (and then click on that new map to enlarge it)

Distribution of social and technological systems in 2000 BCE

Distribution of social and technological systems in 1000 BCE

Distribution of social and technological systems in 500 BCE

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c070CivilizationsEarly.html[11/3/2014 5:16:54 PM] Distribution of social and techn

Distribution of social and technological systems in 200 BCE

See the Discussion page for more detail

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c070CivilizationsEarly.html[11/3/2014 5:16:54 PM] Empires

Empires

Empires developed where there where suitable climatic conditions, available crop plants and/or animals and a sufficiently large population (or conditions that allowed an increase in population from the hunter/gatherer stage). They did NOT develop initially in Europe or Australia. Why?

No indigenous crop plants and/or No indigenous animals for domestication

Note: Australia was “cut off” from the rest of the world 40,000 years ago and had no mammals for domestication nor any suitable crop plants. Imagine trying to domesticate and herd kangaroos or other marsupials. The aboriginal population therefore remained as hunter/gatherers until the arrival of Europeans with wheat, animals (and diseases).

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c080Empires.html[11/3/2014 5:16:54 PM] Barriers affecting Empires

Barriers affecting Empires

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c090Barriers.html[11/3/2014 5:16:54 PM] The Fertile Crescent – General H

The Fertile Crescent – General Historical Context

The Fertile Crescent The Fertile Crescent is the region in the Middle East which encompasses modern-day southern Iraq, Syria, Lebanon, Jordan, Israel and northern Egypt.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c091FertileCrescent.html[11/3/2014 5:16:55 PM] Ancient Chinese Dynasties

Ancient Chinese Dynasties

China is one of the areas where civilization developed earliest. It has a recorded history of nearly 5,000 years.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c092china.html[11/3/2014 5:16:55 PM] The Indus Valley Civilization –

The Indus Valley Civilization – General Historical Context

The Indus Valley Civilization - 3300–1300 BCE

The Indus Valley Civilization (IVC) was a Bronze Age civilization (3300–1300 BCE; mature period 2600–1900 BCE) in the northwestern region of the Indian subcontinent, consisting of what is now mainly present-day Pakistan and northwest India

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c093IndusValley.html[11/3/2014 5:16:55 PM] Egypt – General Historical Conte

Egypt – General Historical Context

Between 5000 and 3100 BCE, Neolithic (late Stone Age) communities in northeastern Africa exchanged hunting for agriculture and made early advances that paved the way for the later development of Egyptian arts and crafts, technology, politics and religion For almost 30 centuries—from its unification around 3100 B.C. to its conquest by Alexander the Great in 332 B.C.—ancient Egypt was the preeminent civilization in the Mediterranean world. People began to settle in the Nile valley in about 7000 B.C.. They farmed the land, kept animals, and built permanent homes on the banks of the Nile.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c095Egypt.html[11/3/2014 5:16:55 PM] Greece – General Historical Cont

Greece – General Historical Context

Map of Ancient Greece showing the major cities

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c097Greece.html[11/3/2014 5:16:55 PM] Rome - General Historical Conte

Rome - General Historical Context

Animated map of the Roman Republic and Empire.

Displayed in the map:

Roman republic 510 BCE-40 BCE

Roman Empire 20 AD-360 AD

Eastern Roman Empire 405 AD-1453 AD

Western Roman Empire 405 AD-480 AD

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c098Rome.html[11/3/2014 5:16:56 PM] The Hydrologic Cycle

The Hydrologic Cycle

This simplified version of the water cycle (the hydrologic cycle) shows the circulation of water in its three phases (liquid, solid [snow] and gaseous [water vapour])

The major functional components of this cycle are:

Precipitation Condensed water vapor that falls to the Earth's surface. Most precipitation occurs as rain, but also includes snow, hail, fog drip,soft hail or snow pellets, and sleet. Approximately 505,000 km3 of water falls as precipitation each year, 398,000 km3 of it over the oceans. The rain on land contains 107,000 km3 (26,000 cu mi) of water per year and a snowing only 1,000 km3 . Canopy interception The precipitation that is intercepted by plant foliage, eventually evaporates back to the atmosphere rather than falling to the ground. Snowmelt The runoff produced by melting snow. Runoff The variety of ways by which water moves across the land. This includes both surface runoff and channel runoff. As it flows, the water may seep into the ground, evaporate into the air, become stored in lakes or reservoirs, or be extracted for agricultural or other human uses.

Infiltration file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c100WaterCycleTitle.html[11/3/2014 5:16:56 PM] The Hydrologic Cycle

The flow of water from the ground surface into the ground. Once infiltrated, the water becomes soil moisture or groundwater. Subsurface flow The flow of water underground. Subsurface water may return to the surface or eventually seep into the oceans. Water returns to the land surface at lower elevation than where it infiltrated, under the force of gravity or gravity induced pressures. Groundwater tends to move slowly, and is replenished slowly, so it can remain in aquifers for thousands of years. Evaporation (Evapotranspiration) The transformation of water from liquid to gas phases as it moves from the ground or bodies of water into the overlying atmosphere. The source of energy for evaporation is primarily solar radiation. Evaporation often implicitly includes transpiration from plants, though together they are specifically referred to as evapotranspiration. Total annual evapotranspiration amounts to approximately 505,000 km3 of water, most of which (434,000 km3) evaporates from the oceans. Sublimation The state change directly from solid water (snow or ice) to water vapor. Deposition This refers to changing of water vapor directly to ice. Advection The movement of water — in solid, liquid, or vapor states — through the atmosphere. Without advection, water that evaporated over the oceans could not precipitate over land. Condensation The transformation of water vapor to liquid water droplets in the air, creating clouds and fog. Transpiration The release of water vapor from plants and soil into the air. Water vapor is a gas that cannot be seen. Percolation Water flows horizontally through the soil and rocks.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c100WaterCycleTitle.html[11/3/2014 5:16:56 PM] Main components of the water cyc

Main components of the water cycle

The major features and components of the water cycle are:

Water Storage in Oceans Ice caps around the world. Oceans in movement Ice and glaciers Evaporation: Contribution of snowmelt to stream flow Evaporation drives the water cycle Surface runoff Sublimation: Main components of the water cycle - Part 2 Evapotranspiration: Importance of rivers Transpiration: Watersheds and rivers Water storage in the atmosphere Groundwater begins as precipitation Condensation: Groundwater storage: Condensation in the air Groundwater flows underground Precipitation: Springs Ice caps around the world.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c105WaterCycle1.html[11/3/2014 5:16:56 PM] Main components of the water cyc

Main components of the water cycle - Part 2

The major features and components of the water cycle are:

Water Storage in Oceans Ice caps around the world. Oceans in movement Ice and glaciers Evaporation: Contribution of snowmelt to streamflow Evaporation drives the water cycle Surface runoff Sublimation: Main components of the water cycle - Part 2 Evapotranspiration: Importance of rivers - Part 2 Transpiration: Watersheds and rivers - Part 2 Water storage in the atmosphere Groundwater begins as precipitation - Part 2 Condensation: Groundwater storage - Part 2 Condensation in the air Groundwater flows underground - Part 2 Precipitation: Springs - Part 2 Ice caps around the world.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c110WaterCycle1.html[11/3/2014 5:16:56 PM] Freshwater Availability on Earth

Water Distribution

Note the small amount of freshwater on Earth (2.5% of the total water) and the even smaller percentage of that 2.5% that is easily available in rivers, lakes, swamps, soil, the atmospher and in organisms (biological water)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c115WaterDistribution.html[11/3/2014 5:16:56 PM] Freshwater Availability on Earth

Atmospheric Water Cycling The earth's water is cycled through the atmosphere (clouds, climate and weather are some of the results of this cycling). It happens on a global scale and is responsible for massive heat transfers around the Earth's atmosphere. Satellites have revealed the scale and complexity of this cycling in both the oceans and the atmosphere and have also revealed other events related to this cycling such as forest fires, vegetation changes, dust clouds, etc.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c116EarthsAtmosphere.html[11/3/2014 5:16:57 PM] Introduction - Water Supplies

Present Situation - Water Supplies and Sanitation

What is the current situation with regard to provision of safe water and sanitation?

According to the United Nations, the world has already (in 2010) met the Millennium Development Goals (MDGs) for increasing by 50% the world population with access to improved drinking water by 2015:

As they state, the quality of this water is unknown so that the improvement in access to safe water is also unknown. The distribution of this improved access across regions and countries is very uneven. To quote the 2012 Report on progress towards the MDGs;

"TARGET: Halve, by 2015, the proportion of the population without sustainable access to safe drinking water and basic sanitation.

The number of people using improved drinking water sources reached 6.1 billion in 2010, up by over 2 billion since 1990. China and India alone recorded almost half of global progress, with increases of 457 million and 522 million, respectively.

The work is not yet done. Eleven per cent of the global population—783 million people—remains without access to an improved source of drinking water and, at the current pace, 605 million people will still lack coverage in 2015.

In four of nine developing regions, 90 per cent or more of the population now uses an improved drinking water source. In contrast, coverage remains very low in Oceania and sub-Saharan Africa, neither of which is on track to meet the MDG drinking water target by 2015. Over 40 per cent of all people without improved drinking water live in sub- Saharan Africa. Since it is not yet possible to measure water quality globally, dimensions of safety, reliability and sustainability are not reflected in the proxy indicator used to track progress towards the MDG target. As a result, it is likely that the number of people using improved water sources is an overestimate of the actual number of people using safe water supplies. Continued efforts are required to promote global monitoring of drinking water safety, reliability and sustainability and to move beyond the MDG water target to universal coverage."

Rural areas fared worse than urban areas Progress towards the MDGs on the sanitation target has been much slower.

"Sanitation coverage increased from 36 per cent in 1990 to 56 per cent in 2010 in the developing regions as a whole. Despite progress, almost half of the population in those regions—2.5 billion—still lack access to improved sanitation facilities."

The greatest progress was achieved in Eastern and Southern Asia, where sanitation coverage in 2010 was, respectively, 2.4 and 1.7 times higher than in 1990. In contrast, progress was slowest in Western Asia and sub- Saharan Africa, and no improvement was achieved in Oceania over the 20-year period. At the current pace, and barring additional interventions, by 2015 the world will have reached only 67 per cent coverage, well short of the 75 per cent needed to achieve the MDG target."

"The number of people who do not use any facility and resort to open defecation has decreased by 271 million since 1990. But there remain 1.1 billion people—or 15 per cent of the global population—with no sanitation facilities at all. Daily, entire communities are exposed to the considerable health and environmental hazards of inadequate human waste disposal. In 11 countries, a majority of the population still practices open defecation. Even in countries with rapidly growing economies, large numbers of people still must resort to this practice: 626 million in India, 14 million in China and 7 million in Brazil. Nearly 60 per cent of those practicing open defecation live in India."

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c120PresentSituation.html[11/3/2014 5:16:57 PM] Introduction - Water Supplies

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c120PresentSituation.html[11/3/2014 5:16:57 PM] The Hydrologic Cycle Looking at our Earth from space, with its vast and deep oceans there is an abundance of water for our use. However, only a small portion of Earth's water is accessible for our needs. How much fresh water exists and where it is stored affects us all. This animation uses Earth science data from a variety of sensors on NASA Earth observing satellites as well as cartoons to describe Earth's water cycle and the continuous movement of water on, above and below the surface of the Earth.

Sensors on a suite of NASA satellites observe and measure water on land, in the ocean and in the atmosphere. These measurements are important to understanding the availability and distribution of Earth's water -- vital to life and vulnerable to the impacts of climate change on a growing world population.

See the Discussion page to play the NASA Video

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c150WaterCycleVideos.html[11/3/2014 5:16:57 PM] The Hydrologic Cycle

Why is water so important?

Essential for all life on Earth Some observations: Each person requires about 2 to 4 litres per day to survive (varies with weight, climatic conditions and activity level)

70% of water is used for agriculture 20% by industry 10% for domestic use

2000 - 5000 litres used to grow daily food intake (1 apple = 70litres, 150g of steak requires 2025 litres, 100g of vegetables require 20 litres, 1 slide of bread requires 40 litres)

Water use has been growing at more than twice the rate of population increase in the last century.

Water withdrawals are predicted to increase by 50 percent by 2025 in developing countries, and 18 per cent in developed countries

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c160Importanceofwater.html[11/3/2014 5:16:57 PM] The Hydrologic Cycle

Climate Change, Water and Health

Floods may increase water-borne parasites Heavy rainfall events cause storm water runoff that may contaminate water bodies used for recreation

Flooding and heavy rainfall can cause overflows from sewage treatment plants into fresh water sources.

Changes in temperature and precipitation, as well as droughts and floods, will likely affect agricultural yields and production.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c170climatechange.html[11/3/2014 5:16:57 PM] Civilizations and Water

Water and Civilizations

Early civilizations were extremely dependent on a constant, reliable water source. Most were founded close to a freshwater source (lake, river or groundwater); this is still true today even with advances in water transport and treatment. Agriculture and water supply are inextricably linked; more water is needed for agriculture than for human consumption. Technological advances in water supply and safety came about after cities were established – agricultural development and food surpluses allowed cities to become established.

Water technologies are normally developed first for irrigation of crops, then for water supplies for people in settlements and cities, sometimes for aesthetic reasons (fountains, pools and local micro- climate modification), for waste disposal and for recreation.

Thus civilization, technological development, agricultural development, urbanization and water supplies are closely linked.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c200WaterandCivilizationTITLE.html[11/3/2014 5:16:57 PM] Civilizations and Water

The Fertile Crescent

About 6,000–7,000 years ago, farming villages of the Near East and Middle East became urban centers. During the Neolithic age (ca. 5700–2800 B.C.), the first successful efforts to control the flow of water were driven by agricultural needs (irrigation). Irrigation probably began to develop at a small scale during the Neolithic age in the so-called “fertile crescent,” an arc constituting the comparatively fertile regions of Mesopotamia and the Levant, delimited by the dry climate of the Syrian Desert to the south and the Anatolian highlands to the north.

Water for irrigation agriculture and human consumption was important in this relatively dry area.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c202WaterandCivilization.html[11/3/2014 5:16:57 PM] Civilizations and Water

Egypt

The Nile River has been the most important water source for Egypt for millenia. A highly developed, but very locally controlled, system of irrigation by flooding the fields developed very early and allowed agriculture to thrive based on the annual floods of the Nile River. This supplied both water and nutrients to the soil.

This local control probably allowed the Egyptians to survive (often violent) changes in Dynasties, rulers and wars since it was not dependent upon centralized control.

Irrigation by canals (from 3000 BCE) from the river and fairly large scale dams (from 2600 BCE) developed later and were important in supporting the increasing population.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c203WaterandCivilization.html[11/3/2014 5:16:58 PM] Civilizations and Water

Greece

The ancient Greeks invented many features of modern civilization. Their achievements in water technology were impressive; in 250 BCE they invented the water mill and in circa 250 BCE they pioneered the water wheel. They had air and water pumps, indoor plumbing, central heating, showers and built canal locks and an ancient version of the Suez Canal.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c205WaterandCivilization.html[11/3/2014 5:16:58 PM] Civilizations and Water

Rome

Pont-du-Gard - Roman Aqueduct

Rome developed many water transport systems, some of amazing complexity and sophistication, using siphons to move water uphill, aqueducts to cross valleys, dams to store and control water, piped water in cities, water wheels and cisterns for storing water. After the fall of the Roman Empire, many of these structures decayed and were not equaled until much later in history

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c260WaterandCivilization.html[11/3/2014 5:16:58 PM] Civilizations from 1000 AD to th

Civilizations from 1000 AD to the present

In the past 1000+ years there have been developments in sanitation and water technologies, but in overall terms, most of the innovations were already there in the ancient European, Middle Eastern, Asian and South American civilizations.

In many cases, those early innovations were essentially lost until later in history and, in the Dark Ages in Europe, the water and sanitation systems were inferior to those earlier civilizations.

In many parts of the world, the lack of progress can be partially explained by the constant warfare and invasions that occurred throughout this period.

Some advances in engineering and technology did occur in the 16th, 17th and 18th centuries but large improvements in the health and hygiene of the populations did not happen until late in the 19th century in Europe. This occurred for many reasons, including water treatment to remove pathogens and then contaminating chemicals, and led to a much improved population health.

Fundamental changes began to appear as science and knowledge were institutionalized for the first time when the development of modern universities started in the 13th century, and the agricultural world began to industrialize from the 18th century

Sanitation in towns around Europe was one of the great achievements of the 19th century. During the century the role of water in the transmission of several important diseases – cholera, dysentery, typhoid fever and diarrhoeas – was realized. The final proof came when the microbes causing these diseases were discovered. Especially cholera served as a justification for the sanitary movement around the world in the 19th century

In the early 20th century the health problems associated with water pollution seemed to have been resolved in the industrialized countries when chlorination and other water treatment techniques were developed and widely taken into use. Microbiological problems related to water were largely considered a problem of the developing world. However, in the late 20th century the biological hazards transmitted by water emerged again in the post-modern Western world. Anxiety about chemical and radioactive environmental hazards and their impacts on human health mounted in the 1960s. The overall amount of known biological and chemical health hazards transmitted by water increased manifold during the last half of the 20th century.

From: A Brief History of Water and Health from Ancient Civilizations to Modern Times Chloe Parker IWA WaterWiki - http://www.iwawaterwiki.org/xwiki/bin/view/Articles/-ABRIEFHISTORYOFWATERANDHEALTHFROMANCIENTCIVILIZATIONSTOMODERNTIMES (Internet Access Required)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c280AD1000toPresent.html[11/3/2014 5:16:58 PM] European Dominance

European Dominance Why did the European nations come to dominate? A small advantage in European ships and weapons and then the Industrial Revolution

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c281EuropeanDominance.html[11/3/2014 5:16:58 PM] Untitled 1

Population Increase The graph of actual population increase shows the dramatic increase in the last 300 years. Some of this increase can undoubtedly be ascribed to better water management in agriculture, drinking water and sanitation.

For Millenia before that, the population only increased slightly.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c282population.html[11/3/2014 5:16:58 PM] Civilizations from 1000 AD to the present

Summary of All History (or, more accurately, the last 6000 years)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c285HistoryWorldoneChart.html[11/3/2014 5:16:58 PM] Civilizations from 1000 AD to the present

The chart shows the various empires, dynasties and other civilizations from about 3500 BCE to the present day in the different regions of the world

Note that the various Indian and Chinese empires and dynasties have existed until the present day, the American ones survived for a very long time until the Aztecs were conquered by Spain.

The rise of the Greco-Roman civilizations replaced the power of the Egyptian and Sumerian/Assyrian/Persian ones around 100 to 30 BCE

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c285HistoryWorldoneChart.html[11/3/2014 5:16:58 PM] Global Health Risks

Water and Global Health Risks The global burden of diseases and injuries - World Health Organization 2009 update (on CD) World Health Statistics - 2013 - World Health Organization (on CD)

The five leading global risks for mortality in the world are high blood pressure, tobacco use, high blood glucose, physical inactivity, and overweight and obesity. They are responsible for raising the risk of chronic diseases, such as heart disease and cancers. They affect countries across all income groups: high, middle and low.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c300GlobalHealthRisksTitle.html[11/3/2014 5:16:59 PM] Water and Sanitation-related Dis

Water and Sanitation-related Diseases

1. Waterborne Diseases

Waterborne diseases are caused by pathogenic microbes that can be directly spread through contaminated water. Most waterborne diseases cause diarrheal illness [Note: not all diseases listed below cause diarrhea]. Eighty-eight percent of diarrhea cases worldwide are linked to unsafe water, inadequate sanitation or insufficient hygiene.

These cases result in 1.5 million deaths each year, mostly in young children. The usual cause of death is dehydration. Most cases of diarrheal illness and death occur in developing countries because of unsafe water, poor sanitation, and insufficient hygiene.

Other waterborne diseases do not cause diarrhea; instead these diseases can cause malnutrition, skin infections, and organ damage.

2. Sanitation & Hygiene-Related Diseases

Sanitation and hygiene are critical to health, survival, and development. A significant amount of disease could be prevented through better access to adequate sanitation facilities and better hygiene practices. Improved sanitation facilities (for example, toilets and latrines) allow people to dispose of their waste appropriately, which helps break the infection cycle of many diseases.

Hygiene refers to acts that can lead to good health and cleanliness, such as frequent hand washing, face washing, and bathing with soap and clean water. Practicing personal hygiene in many parts of the world can be difficult due to lack of clean water and soap.

Providing access to safe water and sanitation facilities, and promoting proper hygiene behavior are important in reducing the burden of disease from sanitation and hygiene-related diseases.

3. Vector or Insect-borne Diseases Associated with Water

Water plays a critical role in the spread of insect-borne diseases because many insects, such as mosquitos, breed around water. An increase in water, especially from flooding, can directly impact the number of mosquitoes and other insects that breed around water, potentially creating high-risk environments for disease.

Infected insects can transmit deadly disease to humans through their bite, such as malaria, dengue fever, and West Nile encephalitis. Worldwide, over one million people die each year due to mosquito-borne diseases, most of them young children in sub-Saharan Africa. Insect-borne diseases are rarely contracted in North America, but some have become more common recently, such as West Nile virus

4. Neglected Tropical Diseases associated with water

Worldwide, approximately 1 billion people are affected by one or more neglected tropical diseases (NTDs). According to the World Health Organization, the diseases are named neglected because they "persist exclusively in the poorest and the most marginalized communities, and have been largely eliminated and thus forgotten in wealthier places". Neglected tropical diseases are most often found in places with unsafe drinking water, poor sanitation and insufficient hygiene practices. These diseases can cause severe pain, disabilities, and death.

Modified from: Center for Disease Control, USA http://www.cdc.gov/healthywater/wash_diseases.html (Internet Access Required)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c350Diseases.html[11/3/2014 5:16:59 PM] Water and Sanitation-related Dis

Modern Water Treatment Systems A combination selected from the following processes is used for municipal drinking water treatment worldwide:

Sedimentation - for solids separation (removal of suspended solids trapped in the floc) Filtration - removing particles from water Desalination - Process of removing salt from the water Disinfection - for killing bacteria.

There is no unique solution (selection of processes) for any type of water. Also, it is difficult to standardize the solution in the form of processes for water from different sources. Treatability studies for each source of water in different seasons need to be carried out to arrive at most appropriate processes. The above mentioned technologies are well developed, and generalized designs are available that are used by many water utilities (public or private). In addition to the generalized solutions, a number of private companies provide solutions by patenting their technologies. The developed world employs a considerable amount of automation for water and wastewater treatment. The developing nations worldwide use automation along with manual operations. The level of automation is a choice of operators. The aspects that govern the choice of level of automation are capital and operating costs, skills available locally, operators comfort, integration of automation & control with rest of the component of water supply and so on.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c360ModernWaterTreatment.html[11/3/2014 5:16:59 PM] Water and Sanitation-related Dis

Sanitation Technologies and Methods Sanitation

Sanitation refers to the safe disposal of human excreta. This entails the hygienic disposal and treatment of human waste to avoid affecting the health of people. Sanitation is an essential part of the Millennium Development Goals. The most affected countries are in the developing world. Population increase in the developing world has posed challenges in the improvement of sanitation. Lack of provisions of basic sanitation is estimated to have contributed to the deaths of approximately 3.5 million people annually from water borne diseases.

The World Health Organization states that: "Sanitation generally refers to the provision of facilities and services for the safe disposal of human urine and feces. Inadequate sanitation is a major cause of disease world-wide and improving sanitation is known to have a significant beneficial impact on health both in households and across communities. The word 'sanitation' also refers to the maintenance of hygienic conditions, through services such as garbage collection and wastewater disposal" The earliest evidence of urban sanitation was seen in Harappa, Mohenjo-daro and the recently discovered Rakhigarhi of Indus Valley civilization. This urban plan included the world's first urban sanitation systems. Within the city, individual homes or groups of homes obtained water from wells. From a room that appears to have been set aside for bathing, waste water was directed to covered drains, which lined the major streets.

Modern Sewage Treatment

Modern sewage treatment is the process of removing contaminants from wastewater and household sewage, both runoff (effluents), domestic, commercial and institutional. It includes physical, chemical, and biological processes to remove physical, chemical and biological contaminants. Its objective is to produce an environmentally safe fluid waste stream (or treated effluent) and a solid waste (or treated sludge) suitable for disposal or reuse (usually as farm fertilizer).

Sewage treatment is the process that removes the majority of the contaminants from wastewater or sewage and produces both a liquid effluent suitable for disposal to the natural environment and a sludge. To be effective, sewage must be conveyed to a treatment plant by appropriate pipes and infrastructure and the process itself must be subject to regulation and controls.

Some wastewaters require different and sometimes specialized treatment methods. At the simplest level, treatment of sewage and most wastewaters is carried out through separation of solids from liquids, usually by sedimentation. By progressively converting dissolved material into solids, usually a biological floc, which is then settled out, an effluent stream of increasing purity is produced.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c370Sanitation.html[11/3/2014 5:16:59 PM] Water as a Source of Conflict

Water as a Source of Conflict

Water as Promoter of Peace Although water can certainly be a source of conflict and even military actions, most water conflicts are resolved peacefully This is because of the importance of water to both (or all) of the countries, regions, or areas involved in the disputes. A settlement where water continues to be available, perhaps with a changed distribution or entitlement, seems to be the most common outcome of water disputes. In many cases the water source itself is very vulnerable to diversion or deliberate overuse. The key element seems to be the relative strength or power of the disputing parties; where they are similar, the dispute is often settled quickly. Where they are very unequal, it may take much longer if it even happens at all.

Most disputes are very local in scope, even down the level of neighbours disputes over water rights or withdrawals.

The list of water conflicts in 2012 from the Water Conflict Chronology website shows that relatively few are large-scale conflicts and most are about local concerns.

Summary:

On balance, most observers think that water conflicts at the international level have normally led to a peaceful resolution through treaties or negotiations. Some local disputes are still occurring and are often more difficult to resolve, although they affect relatively few people. The incidence, scope and importance of acts of terrorism is difficult to predict but could be locally significant .

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c410WaterConflict.html[11/3/2014 5:16:59 PM] Data

Data, Information, Knowledge and Synthesis

There are innumerable sources of information on water issues, health issues and health issues involving water.

They range from sites containing processed information such as graphs and maps, sites with a limited range of data to comprehensive sites containing very large databases encompassing many different subjects.

Quite recently, the United Nations has made most of its vast store of data available to anyone who wants to download it. The United Nations Statistical Division is the agency responsible for these efforts, but many other UN agencies publish such datasets.

Many other datasets are available from governments, NGOs, universities, institutes, private sector companies and others.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c500ListofDatabasesTitle.html[11/3/2014 5:16:59 PM] Other Sources of Data

Other Sources of Data: Waterbase Other useful sources of data include: Waterbase The WaterBase project is an ongoing project of the United Nations University. Its aim is to advance the practice of Integrated Water Resources Management (IWRM) in developing countries. Predictive modeling and decision support for water management in developing countries are plagued with a number of related problems: lack of money, lack of expertise, inadequate training capacity, dependence on experts from other countries. At the same time water resources are under increasing pressure, and aquatic ecosystems are being damaged by people who lack the resources to explore the consequences of decisions before they are made. http://www.waterbase.org (Internet Access Required)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c501Waterbase.html[11/3/2014 5:16:59 PM] Gapminder World

GapMinder Gapminder is a software program and associated databases that allow you to look at world statistical data in a very interactive manner.

You can download "Gapminder Offline" from http://www.gapminder.org/world-offline/ (Internet Access Required) to use on your desktop or you can use the Gapminder web-based program at http://www.gapminder.org/ (Internet Access Required). Both produce similar results.

Gapminder gives an interactive view of the data, in this case, life expectancy versus income, over long time periods. Individual countries can be highlighted and tracked and the axes can be changed.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c510GapMinder.html[11/3/2014 5:17:00 PM] Water Management

Water Management

Management of water sources, supplies and distribution, coupled with waste disposal has been a concern of human societies from the earliest days of human settlements.

The early hunter-gatherer societies were nomadic and travelled between water sources

Early agricultural societies were established close by reliable water sources; irrigation processes developed later

Early city civilizations were also established on or close to water sources and some developed quite sophisticated water management and distribution systems. These systems were sometimes the limiting resources controlling further development.

Greek and Roman cities had reasonably well-developed water systems, but sanitation was usually a more primitive set of processes.

The technologies were lost for many years in Europe after the fall of the Roman Empire and were not reintroduced until the 18th and nineteenth centuries.

In the late 19th century, water management and safe water supplies became an important issue in the rapidly expanding towns and technologies for water treatment and sanitation were developed.

At the same time, it became clear that better water management methods were required; too many people and agencies were managing different aspects of the water cycle and human consumption and they often had competing and conflicting goals.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c800WaterManagementTitle.html[11/3/2014 5:17:00 PM] Water Management

Water Management Recent Developments in Water Management

In the 20th Century, water management and sanitation developed into a complex interacting system in the industrialized countries.

It started as a set of individual management processes for the various resources (water supply, purification and distribution, and waste disposal systems), but it soon became evident that these resources needed to be coordinated to be most effective and safe.

During the past 80 years an evolving integration of these processes, and the institutions operating them, has happened.

More recently, the concept of Integrated Water Resource Management (IWRM) has come to be the dominant theoretical basis for integrating and managing all of the complex set of resources, processes, governance structures, social and legal issues that surround water and sanitation management

The usual scale of IWRM is at the watershed, or drainage basin scale.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c810WaterManagement1.html[11/3/2014 5:17:00 PM] Water Management

Water Management Integrated Water Resource Management (IWRM)

IWRM developed from early concepts of integrating water agency and institutional activities to today's concept of adaptive management of integrated water and sanitation systems on a watershed scale where all the interests of all the people and institutions are taken into account.

IWRM is the theoretical basis for a process to do this, but particular IWRM plans are developed for each instance. There is no "common template" for IWRM for every watershed; it has to be developed through extensive consultations to take into account the interests of all of the stakeholders.

The evolution of IWRM was a slow process and evolved through four main stages: 1. The Sectoral Approach - 1820 to 1950s 2. The Cooperative Approach - 1960s and 1970s 3. Management-oriented IWRM - 1980s 4. Goal-oriented IWRM - 1990s to present

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c820IWRM.html[11/3/2014 5:17:00 PM] Towards IWRM

Towards IWRM

"IWRM is not a new idea, (it evolved) in the 1970s-80s as a response to sectoral approaches to water management.

While the conceptualization of the idea (cross-sectoral, participatory-driven, co-ordinated approaches to land and water management, on a watershed basis, at the scale of river valleys and river basins), has captured much interest and action, little work has been done in developing a rigorous theoretical basis.

IWRM derives from new approaches to resource management and planning, one which seeks collaboration and consensus building and using a systems approach to resource management.

The challenge remains to build this theoretical framework – should it be built solely on systems theory, or on a theory of consensual planning, on a theory of ecosystems science?"

Bruce Hooper

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c830TowardsIWRM.html[11/3/2014 5:17:00 PM] Progress towards IWRM

Progress towards IWRM?

More and more agencies are establishing administrative frameworks that permit and even encourage the management of water on a watershed basis.

Less frequently, however, is the management of water integrated with that of other resources that affect or are affected by water.

These other resources may include, at minimum, the intensity and nature of agricultural activities, forestry, and commercial fisheries.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c835ProgressIWRM.html[11/3/2014 5:17:00 PM] Water Management

Water Management - Summary Integrated Water Resource Management The process of IWRM has been described in many documents from many different sources, but the general consensus of most is based on the broadly accepted definition of IWRM as: "a process which promotes the coordinated development and management of water, land and related resources in order to maximize economic and social welfare in an equitable manner without compromising the sustainability of vital ecosystems and the environment " The Global Water Partnership (Internet Access Required)

This evolved from the Dublin Statement and Conference Report [on CD] (1992) and express a holistic, comprehensive, multi-disciplinary approach to water resource problems worldwide. It is based on four “guiding principles” which cover environmental, social, political, and economic issues:

1. “Fresh water is a finite and vulnerable resource, essential to sustain life, development, and the environment. . .”

2. “Water development and management should be based on a participatory approach, involving users, planners, and policy-makers at all levels. . .”

3. “Women play a central part in the provision, management, and safeguarding of water. . .”

4. “Water has an economic value in all its competing uses and should be recognized as an economic good. . . .”

The emphasis of the Dublin Statement on the economic value of water rather than water as a universal right is highly contested by NGOs and human rights activists. Up till today it is still the only binding UN document that makes a statement on the issue. In November 2002, however, the UN Committee on Economic, Social and Cultural Rights (Internet Access Required) adopted General Comment No. 15, which was formulated by experts as a comment on articles 11 and 12 of the International Covenant on Economic, Social and Cultural Rights. (Internet Access Required) In this comment, water is recognized not only as a limited natural resource and a public good but also as a human right. This step - adopting General Comment No. 15 - is seen as a decisive step towards the recognition of water as universal right, although the document has no legally binding power.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c840IWRM1.html[11/3/2014 5:17:01 PM] IWRM Problems and Issues

IWRM Problems and Issues The process of IWRM has not been without its critics; many people have criticized many aspects of the process and its results. In their paper -"Finding Practical Approaches to Integrated Water Resources Management" , John Butterworth, Jeroen Warner, Patrick Moriarty, Stef Smits and Charles Batchelor deal with many of those criticisms and suggest potential solutions.

ABSTRACT: Integrated Water Resources Management (IWRM) has often been interpreted and implemented in a way that is only really suited to countries with the most developed water infrastructures and management capacities. While sympathetic to many of the criticisms leveled at the IWRM concept and recognizing the often disappointing levels of adoption, this paper and the series of papers it introduces identify some alternative ways forward in a developmental context that place more emphasis on the practical in finding solutions to water scarcity. A range of lighter, more pragmatic and context-adapted approaches, strategies and entry points are illustrated with examples from projects and initiatives in mainly 'developing' countries. The authors argue that a more service- orientated (WASH, irrigation and ecosystem services), locally rooted and balanced approach to IWRM that better matches contexts and capacities should build on such strategies, in addition to the necessary but long-term policy reforms and river basin institution-building at higher levels. Examples in this set of papers not only show that the 'lighter', more opportunistic and incremental approach has potential as well as limitations but also await wider piloting and adoption.

Butterworth, J.; Warner, J.; Moriarty, P.; Smits, S. and Batchelor, C. 2010. "Finding practical approaches to Integrated Water Resources Management". www.water-alternatives.org Volume 3 Issue 1 Local version: IWRMconcepts and practice.pdf (on CD)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c850IWRMEXTRA.html[11/3/2014 5:17:01 PM] Distribution of Water on the Ear

Summary

We have seen the central importance of water to life on Earth and how it is distributed and cycled through the atmosphere, fresh and sea water.

It is an unfortunate fact that only a very small percentage of water is fresh water available for human consumption and use.

The population is increasing to 9 billion by 2050 and large parts of the Earth, mainly developing countries, will be under even more severe water stress than they are now.

The history of civilizations over the centuries is one of improvement in technologies of water management and supply, at even a fairly rapid rate during the Greco-Roman era, followed by a long period of dormancy until the Renaissance and the 19th century, when increasing populations spurred efforts to clean and supply water to the rapidly increasing city populations.

As the knowledge about the health issues surrounding water such as microbiological contamination and chemical pollution increased, more effort was devoted to water treatment and sanitation technologies. Eventually, chlorination of water supplies and safer distribution systems led to a drastic increase in the safety of the water supply leading to the eradication in developed countries of most water-borne infectious diseases. Even so, periodic outbreaks of protozoal and viral water-related diseases require constant vigilance.

It is important to remember that water issues and problems cannot be dealt with in isolation; just considering the interactions between water, food and energy, it is clear that they are closely related and interdependent. To solve water problems many related issues must be considered. In a similar vein, food problems cannot be solved without considering water and energy issues.

It is also important to recognize the gains that have been made on the last two decades in supplying safe water and sanitation to much of the world's population previously without it.

Subsequent courses in this programme will deal with some of these topics in more detail and will introduce other topics in water and health.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c890Summary.html[11/3/2014 5:17:01 PM] References List

Reference Materials

The Concept and Discussion Pages are identical

Bibliography

On-line Bibliography for IWRM

There is a substantial (+3200 references) bibliographic database available for searching on all aspects of IWRM, including water-health issues, at the Mendeley Website http://www.mendeley.com/groups/search/?query=un+water (Internet Access Required)

Search for "UN Water Learning Centre" go to "Papers" in the left-hand section and you can then search that IWRM database for any one of hundreds of keywords.

Go directly there now (Internet Access Required)

Briefly, to perform a full search on the numerous "tags" in the Bibliography, download the up-to-date full list of "Tags" from http://www.colinmayfield.com/wlc/tagslisting.txt (Internet Access Required). A local version of the listing of tags is here. This version may not be completely up-to-date.

Then, when in the "papers" section of the Group, click on any one of the "Top Tags" from the right-hand sidebar and replace its name in the URL bar at the top of the browser with the one you want to use.

The reason for this convoluted process is that Mendeley does not allow searches on all of the tags, only on a predetermined set of popular tags.

Extra Reading Materials on the CD - A selected List

If accessing this list causes problems (the browser does not return properly to the course materials), try right-clicking on the link and "open in a new window" or "Open in a new tag" or similar instructions in other browsers.

Disease

World Health Statistics - WHO 2012

Water-based diseases - Bachurova - IWA

Global health Risks - WHO 2010

Which Came First: Burden of Infectious Disease or Poverty? - Chase - PLOS 2010

Bibliography of Safe Water, Small Scale and Household Water Treatment - Microsoft Word

Drinking Water

Drinking Water Quality - Parker - IWA

Bibliography of Safe Water, Small Scale and Household Water Treatment - Microsoft Word

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c950ReferenceMaterial.html[11/3/2014 5:17:01 PM] References List

History

A Brief History of Water and Health - Parker - IWA

Ancient Water Technologies - Mays - Springer

Building terrestrial planets Morbidelli, Lunine, O'Brien, Raymond and Walsh

Water Gods – From Wikipedia

Health

Health Impact Assessment for Sustainable Water Management - Parker - IWA

Health-related Risk Assessment - Parker - IWA

Bibliography of Safe Water, Small Scale and Household Water Treatment - Microsoft Word

IWRM

The Dublin Statement

Web Issue Analysis: An Integrated Water Resource Management Case Study - Thelwall, Vann and Fairclough

Practical Approaches to IWRM - Butterworth, Warner, Moriarty, Smits and Batchelor - PLOS 2010

IWRM at a Glance - GWP

IWRM Background - For sustainable use of water - Snellen and Schrevel 2004

IWRM Brochure - Guidelines at a River basin Level - WWAP - UINESCO

Finding Practical Approaches to Integrated Water Resources Management - Butterworth, Warner, Moriarty, Smits and Batchelor

Water Conflict Chronology Timeline - Pacific Institute

Water for Peace - WWAP - UNESCO

Patterns in International Water Resource Treaties - Hamner and Wolf 1998

The Millenium Development Goals Report 2012 - UN

Safe Water for the Community - CDC

Water for Peace - WWAP - UNESCO

Sanitation

Sanitation - Miller -IWA

Helping Sanitation Enter the Era of Sustainability - Miller - IWA

Bibliography of Safe Water, Small Scale and Household Water Treatment - Microsoft Word

Water Quality

Water Quality and Purity - Parker - IWA

Bibliography of Safe Water, Small Scale and Household Water Treatment - Microsoft Word

file:///F|/Dropbox/WaterHealthNewFinal/Course1/concepts/wh001mo001c001c950ReferenceMaterial.html[11/3/2014 5:17:01 PM] Water and Health Title Page

Water and Health Programme Course 1 - Introduction

How to use the course materials:

You may also add notes to any page or highlight materials for later study.

For Help with the StudySpace software, see the Help Section on the left-hand menu. To see a PowerPoint Presentation on the StudySpace software used in these Water-Health courses see this link. PowerPoint or PowerPoint Viewer (free from Microsoft) is required and PowerPoint Viewer is included for installation from the CD

In short, everything you need to know for this series of courses is on the CD,, but you have been given extra materials and internet references to supplementary materials for clarification if needed, for later use if it is relevant, or for you to pursue individual topics for your own interest.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d000TitlePage.html[11/3/2014 5:18:27 PM] Water and Health Title Page

Water and Health Programme Introduction to the Programme

The Water and Health Programme consists of a number of individual courses addressing the many issues surrounding the relationships between water and the health of people and populations.

Overview of Water-Health Programme Courses

Course 1 Introduction to Water & Health

History of Early Civilizations

History of Water

History of Water and Health

Global Water Issues – importance of water, current access to water and sanitation, history of water resources.

Global Health Issues – water quantity, water quality and health overview; global burden of waterborne disease; history of water-health; London cholera outbreak case study.

Water Supply (Water Quantity and Quality) - water cycle, hydrology, case studies for surface water e.g., Lake Victoria, marine and oceanic systems, groundwater.

Global Water Use and the Hydrogeological cycle – Patterns of use (global and regional) Consumptive versus non- consumptive uses, comparison of patterns of use, types of use and trends - water for human consumption, water for food, water for energy, water for industry, water for ecosystem health, water for recreation and tourism; management approaches for multiple uses IWRM watershed management.

Water Management and Introduction to IWRM – A brief overview of the history and practices of Integrated Water Resource Management

Information Sources on Water and Water-Health issues

Course 2 Water-Related Impacts on Health – Principles, Methods and Applications

Introduction – Viewing water and health through different macro lenses of user of water, needs and usage of water, quality of water and availability of water. Closer look at the intersection of these lenses where impacts occur from a needs assessment and risk assessment perspective. Look at processes for the identification of potential hazards and impacts and standard methods for evaluating prioritizing and reporting acute and chronic exposures to different types of contaminants and applied in assessing and responding in situations with threats of significant potential for causing harmful effects local scale and global scale. Health issues associated with extreme events, watershed diseases, hygiene and drought and flooding.

Water Quality – What are contaminants affecting water quality, biological microbiological and chemical and physical. What are pollution sources, point source and diffuse non-point sources.

Impacts of Water Quantity and Quality on Health – Impacts of water quality and quantity on environmental and public health. Practical methods for measuring and assessing water quality, methods for monitoring and surveillance of water quality and hygiene for use by households, schools, and the community.

Exposure - Disease transmission routes and exposure routes and exposure pathways to contaminants in water, pathogens and parasites and toxic chemicals. Acute and chronic exposures. The faecal-oral exposure pathway of disease and zoonosis. Factors influencing exposures, including differences in life-stages, children, pregnant women and other vulnerable populations.

Toxicology Epidemiology and Risk Assessment - Basic principles and methods and applications. Brief history of epidemiology and application of demographics pertaining to water-related disease. General risk assessment frameworks and integration of risk communication and risk management, including deterministic versus probabilistic risk assessment, cumulative risk assessment, and qualitative and quantitative studies. Drinking water guidelines by the World Health Organization and their development and application.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d001Introduction.html[11/3/2014 5:18:27 PM] Water and Health Title Page

Case studies - Examples of case studies and different types of contaminants and exposure pathways such as, food contamination, guinea worm, arsenic in drinking water, fluoride, pesticides and pharmaceuticals and personal care products.

Social surveys – What are social surveys. How are social surveys conducted and constructed. Data analysis and information.

Risk Communication and Risk Management Challenges –Demographics, language and literacy, and hazard identification of public health emergency of international concern.

Course 3 Technical Solutions for Water & Health

Water Treatment Methods and Water Distribution Systems– Introduction to safe drinking water and the multiple-barrier approach and other water treatment methods. Novel water treatment and purification systems. Examples of different types of water distribution systems. Household water treatment systems.

Source Water Protection - Protecting the source water supply and health issues associated with water treatment and distribution (see also Course 1 and 2). To be added in future are the following topics –water towers, reservoirs, cisterns and rain barrels and other rain and water collection and storage methods for water supply and case studies.

Point of Use, Conventional Drinking Water Treatment, and Advanced Drinking Water Treatment - Selection for the optimization of treatment system configuration- multiple barrier approach.

Sanitation and Wastewater Treatment systems including - Decentralized Treatment, Constructed Wetlands, Conventional Waste Water Treatment, and Advanced Waste Water Treatment -– Overview, sanitation hygiene and wastewater, Ecosan, waste treatment systems, health issues associated with waste treatment (see also Course 1 and 2), non-technical solutions (constructed wetlands). Resource materials are provided on education and participatory approaches. Case studies of wastewater treatment and wetlands construction.

Course 4 Water Ethics, Governance, Law, Economics and Social Intervention

Water and Ethics

Human Rights & Social Justice

Managing Water

Integrating Water and Health

Challenges to Integration

Moving Forward -- Managing Watersheds for Health

Course 5 Challenges for WaSH

Introduction – About 2.5 billion people lack improved sanitation facilities, and 768 million people still use unsafe drinking water sources, according to the latest estimates of the WHO/UNICEF Joint Monitoring Programme for Water Supply and Sanitation (JMP), released in early 2013. Inadequate access to safe water and sanitation services, coupled with poor hygiene practices, kills and sickens thousands of children every day, and leads to impoverishment and diminished opportunities for thousands more.

Challenges for WaSH - The following challenges for WaSH are discussed in the course: disease prevention; disease intervention; maternal health; newborn infant and preschool health; school health.

Water and Sanitation -The importance of water and sanitation in religious and cultural traditions, and in ecological food webs and food networks.

Applications of WaSH – including WaSH and Energy; WaSH and social well-being; WaSH and Tourism, and WaSH in disasters. Case studies for WaSH file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d001Introduction.html[11/3/2014 5:18:27 PM] Water and Health Title Page

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d001Introduction.html[11/3/2014 5:18:27 PM] Untitled 1

Course 1 - Introduction to the Water-Health programme

Overview

To see a PowerPoint Presentation on the StudySpace software used in these Water-Health courses see this link on the CD.

PowerPoint or PowerPoint Viewer (free from Microsoft) is required and it is included for installation from the CD

Early History of the Earth

The history of water and civilizations

Human evolution and water - Prehistoric times

Ancient civilizations and water

The last 1000 years

Progress through the centuries

The Water Cycle

The Hydrologic cycle

Cycling of water

Quantity of water recirculating in the cycle

Residence times of water in various parts of the cycle

Amount of water available for use by populations

Global Climate Change and its Effects on the cycle

Water Resources (details of surface, water, groundwater, oceanic and coastal systems)

Water availability

Why Water is important in Health

Global Water Issues

Population Pressure

Water quantity

Water uses

Water quality issues

Distribution

Patterns of use

Global and regional

Consumptive and non-consumptive

Uses of water

Drinking water (municipal, treated at home, untreated)

Agriculture (arable, animal watering, aquaculture, etc) file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d002Course1.html[11/3/2014 5:18:27 PM] Untitled 1

Industrial

Ecosystem requirements

Water and Civilizations

Ancient Water Systems

1000 CE to the Present day

Civilization Timeline and History Overview

Global Health Issues related to water

Overview of water related illnesses and health problems

Water requirements for health

Water requirements for other activities

Water and Diseases

Water Quantity, Quality, Health requirements (hygiene and sanitation)

Oveview of Water Treatment

Overview of Sanitation

Water Conflicts

Water Management

Integrated Water Resource Management

History, Theory, Practices, Outcomes and Assessment

Data and Information Access

Bibliographic Information

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d002Course1.html[11/3/2014 5:18:27 PM] Introduction - Water Supplies

Historical background to water and health - 2

Complete History of the Earth - The Geologic Time Clock

All of the Earth’s evolution expressed as a clock with 12 hours in a different graphical representation

Notice that:

2. Eukayotes emerged just over 2 billion years ago followed by multicellular organisms about 1.5 billion years ago

3. Land plants evolved at 450 million years ago allowing land animals to evolve

4. The first vertebrates occurred around 380 millions years ago and dinosaurs existed from 230 to 65 million years ago

5. First humans at 2 millions years ago (it almost doesn’t show on the clock!)

6. Modern recorded history and civilization only occupies the last 10,000 years (or less than the blink of an eye on the 12 hour clock!)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d003EarlyHistory1Title.html[11/3/2014 5:18:27 PM] Introduction - Water Supplies

The geologic time scale (GTS) is a system of chronological measurement that relates stratigraphy to time, and is used by geologists, paleontologists, and other earth scientists to describe the timing and relationships between events that have occurred throughout Earth's history. The table of geologic time spans presented here agrees with the dates and nomenclature set forth by the International Commission on Stratigraphy standard color codes of the International Commission on Stratigraphy. Evidence from radiometric dating indicates that the Earth is about 4.54 billion years old.

Extra Material:

The geology or deep time of Earth's past has been organized into various units according to events which took place in each period. Different spans of time on the GTS are usually

delimited by changes in the composition of strata which correspond to them, indicating major geological or paleontological events, such as mass extinctions. For example, the boundary

between the Cretaceous period and the Paleogene period is defined by the Cretaceous–Paleogene extinction event, which marked the demise of the dinosaurs and many other groups of

life. Older time spans which predate the reliable fossil record (before the Proterozoic Eon) are defined by the absolute age. (from Wikipedia

http://en.wikipedia.org/wiki/Geologic_time_scale)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d003EarlyHistory1Title.html[11/3/2014 5:18:27 PM] A simpler view of the history of

Where did the water come from?

A simpler view of the history of the Universe and the Earth.

Humans appear in the last few minutes of the clock.

All of recorded history is shorter still!

There are many interesting questions (many still to be answered) about this evolutionary process

An interesting one from our point of view in this course is "Where did the water come from on Earth?"

That question is not as easy to answer as one might expect!

In a paper on the formation of planets, Morbidelli et al. (Adobe Reader required) model the early evolution of differently-sized planets and speculate that water could have come from three sources;

2. From water contained in comets bombarding the early Earth (although their models show this could only have contributed about 10% of the water)

3. By the early Earth accreting water by bombardment with primitive very small planets and asteroids present in the outer asteroid belt. According to their calculations, this could account for sufficient water accumulation during the later stages of Earth's formation

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d005Sourceofwater.html[11/3/2014 5:18:28 PM] A simpler view of the history of

Wherever the water came from, it now comprises about 0.0005 to 0.005 of the Earth's mass - a significant but still small percentage. The evolution of life could not proceed until there was liquid water and the first procaryotes (single celled organisms with no distinct membrane around their nucleus) evolved in that water around 4.2 billion years ago. They eventually produced atmospheric oxygen in sufficient quantities for single-celled eucaryotes (with a nuclear membrane) to evolve followed by multicellular eucaryotes, marine animals ( which later colonized the land surface), followed by primates and humans.

A video of stages in the formation of the Earth is available at http://www.bbc.co.uk/science/earth/earth_timeline (Internet Connection Required)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d005Sourceofwater.html[11/3/2014 5:18:28 PM] Human Migration Timeline

Human Migration Timeline

In an excellent analysis of human genetics, Stephen Oppenheimer was able to trace the migration routes of humans from Africa around the entire Earth over a period of 160,000 years.

The results were compiled and presented in an interactive animation available on-line at http://www.bradshawfoundation.com/journey/ (Internet Access Required). With this, you can track the migration of humans and relate it to major climatic events such as the glaciation periods, large volcanic eruptions causing climate change and other factors. Based on a synthesis of the mtDNA and Y chromosome evidence with archaeology, climatology and fossil study, Stephen Oppenheimer has tracked the routes and timing of migration, also placing it in context with ancient rock art around the world.

Also available is the Journey of Mankind lecture film at http://www.bradshawfoundation.com/stephenoppenheimer/journey_of_mankind.php. (Internet Access Required)

If you have problems with the video playing intermittently, allow more of it to download by pressing "Pause" and waiting till more video has downloaded before starting to "Play" again.

The image below is the final view of human migration patterns from the website. Click the image to go to the animation on the Internet at http://www.bradshawfoundation.com/journey/ (Internet Access Required)

Homo sapiens are supposed to have appeared in East Africa around 200,000 years ago. The oldest individuals found left their marks in the Omo remains (195,000 years ago) and the Homo sapiens idaltu (160,000 years ago), that was found at the Middle Awash site in Ethiopia. Recent claims of remains of anatomically modern humans from 400,000 years ago, found at Qesem Cave (Israel), are controversial. Some authors argue that these remains are from Neanderthals or their ancestors. From there they spread around the world. An exodus from Africa over the Arabian Peninsula around 125,000 years ago brought modern humans to Eurasia, with one group rapidly settling coastal areas around the Indian Ocean and one group migrating north to steppes of Central Asia. There is some evidence for the argument that modern humans left Africa at least 125,000 years ago using two different routes: the Nile Valley heading to the Middle East, at least into modern Israel (Qafzeh: 120,000–100,000 years ago); and a second one through the present-day Bab-el-MandebStrait on the Red Sea (at that time, with a much lower sea level and narrower extension),

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d008HumanMigration.html[11/3/2014 5:18:28 PM] Human Migration Timeline

crossing it into the Arabian Peninsula, settling in places like the present-day United Arab Emirates (125,000 years ago) and Oman (106,000 years ago)] and then possibly going into the Indian Subcontinent (Jwalapuram: 75,000 years ago). Despite the fact that no human remains have yet been found in these three places, the apparent similarities between the stone tools found at Jebel Faya, the ones from Jwalapuram and some African ones suggest that their creators were all modern humans. These findings might give some support to the claim that modern humans from Africa arrived at southern China about 100,000 years ago (Zhiren Cave, Zhirendong, Chongzuo City: 100,000 years ago, and the Liujiang hominid: controversially dated at 139,000–111,000 years ago). Since these previous exits from Africa did not leave traces in the results of genetic analyses based on the Y chromosome and on MtDNA (which represent only a small part of the human genetic material), it seems that those modern humans did not survive or survived in small numbers and were assimilated by our major antecedents. An explanation for their extinction (or small genetic imprint) may be the Toba catastrophe theory (74,000 years ago). However, some argue that its impact on human population was not dramatic. According to the Recent African Origin theory a small group living in East Africa migrated north east, possibly searching for food or escaping adverse conditions, crossing the Red Sea about 70 millennia ago, and in the process going on to populate the rest of the world. According to some authors, based in the fact that only descendants of a particular genic group (L3) are found outside Africa, only a few people left Africa in a single migration to a settlement in the Arabian peninsula. From that settlement, some others point to the possibility of several waves of expansion close in time. For example, Wells says that the early travelers followed the southern coastline of Asia, crossed about 250 kilometers [155 miles] of sea (probably by simple boats or rafts]), and colonized Australia by around 50,000 years ago. The Aborigines of Australia, Wells says, are the descendants of the first wave of migration out of Africa. There is some evidence (Internet Access Required) that the human race was reduced to about 10,000 individuals 74,000 years ago. We only just escaped extinction! Around 50,000 years ago the world was entering the last ice age and water was trapped in the polar ice caps, so sea levels were much lower. Today at the Gate of Grief the Red Sea is about 12 miles (20 kilometres) wide but 50,000 years ago it was much narrower and sea levels were 70 metres lower. Though the straits were never completely closed, there may have been islands in between which could be reached by simple rafts. Shell middens 125,000 years old indicate that the diet of early humans in Eritrea included sea food obtained by beachcombing. This has been seen as evidence that humans may have crossed the Red Sea in search of food sources on new beaches. Modified from: Wikipedia: http://en.wikipedia.org/wiki/Early_human_migrations (Internet Access Required)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d008HumanMigration.html[11/3/2014 5:18:28 PM] History of Civilization

Timelines of Ancient Civilizations

Some initial observations:

No major health differences between populations on the various continents during the Stone Age. We all started from the same place as hunter-gatherers. At least four more stages in development after that:

1. Hunter-gatherer societies (up to about 10,000 years ago) 2. Agriculture (10,000 to 5,000 years ago) 3. Empires (5,000 to 1,000 years ago) 4. European dominance (1,000 to 50 years ago) 5. The present day The next few pages provide a capsule view of the stages in development and important civilizations and their relation to water over the centuries. We also will attempt to explain the divergence between different parts of the world in terms of development of civilizations and technology.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d010TimelineCivilization.html[11/3/2014 5:18:28 PM] Hunter-gatherer society

Prehistoric and Hunter-Gatherer Societies

A hunter-gatherer society is one whose primary subsistence method involves: 1) direct procurement of edible plants and animals from the wild, and 2) foraging and hunting without significant recourse to the domestication of either.

The Mesolithic or "Middle Stone Age” was the period in the development of human technology between the Paleolithic and Neolithic periods of the Stone Age. Flint tools, bows, fishing tackle and canoes appear.

The Neolithic, or “New Stone Age” was an era of primitive social and technological development including villages, agriculture, animal domestication

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d040HunterGatherer.html[11/3/2014 5:18:28 PM] Agriculture and Human Developmen

Agriculture and Human Development

A major change occurred about the 10th millennium BCE with the adoption of agriculture. The Sumerians first began farming c. 9500 BCE. By 7000 BCE, agriculture had been developed in India and Peru separately; by 6000 BCE, to Egypt; by 5000 BCE, to China.

• About 2700 BCE, agriculture had come to Mesoamerica.

• Although attention has tended to concentrate on the Middle East's Fertile Crescent, archaeology in the Americas, East Asia and Southeast Asia indicates that agricultural systems, using different crops and animals, may in some cases have developed there nearly as early.

• The development of organized irrigation, and the use of a specialized workforce, by the Sumerians, began about 5500 BC. Stone was supplanted by bronze and iron in implements of agriculture and warfare.

• Agricultural settlements had until then been almost completely dependent on stone tools. In Eurasia, copper and bronze tools, decorations and weapons began to be commonplace about 3000 BC. After bronze, the Eastern Mediterranean region, Middle East and China saw the introduction of iron tools and weapons

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d050Agriculture1.html[11/3/2014 5:18:28 PM] Agriculture

The Origins of Agriculture

Major Crops

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d060Agriculture2.html[11/3/2014 5:18:29 PM] Agriculture

The 5 most important crops were, and are:

• Wheat - in Syria/Turkey/Iran

• Maize - in Mexico

• Rice - in China

• Potato - in Peru

• Cassava - in Brazil

• The “other five” are millet, sorghum, sweet potato, yams and bananas

Domesticated animals were, and are:

• Cow, horse, sheep, pig, goat, camel, llama, chicken, duck and turkey.

• and NOT – water buffalo, zebra, kangaroo, wombat, etc.

Why these plants and animals?

· Why at these locations?

· Why not elsewhere?

· Why have there been no new discoveries of “domesticatable” plants or animals?

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d060Agriculture2.html[11/3/2014 5:18:29 PM] Agriculture

The simple answers:

· Where nature provided suitable animals and plants for domestication, people developed agriculture.

· All major domestic crops and animals were in use 4000 years ago. No others have been found since then, although many have been tried.

· Notice: none of the crops are native to Europe The result was that: Agriculture enabled the population to increase by 100-fold from 10 million at the end of the Stone Age to 1 billion at the beginning of the Industrial Revolution (circa 1810-1820). More food improved nutrition and general health but, because of increased population density, led to the spread of new and infectious diseases such as measles and smallpox. May also have resulted in more deficiency diseases (iron and others) However, overall effect was favourable as shown by increased population.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d060Agriculture2.html[11/3/2014 5:18:29 PM] Distribution of social and techn

Distribution of social and technological systems in early history - An Overview

Click on each map for a larger version in a new window (and then click on that new map to enlarge it)

Distribution of social and technological systems in 2000 BCE

There are one or two state societies in the Middle East and South America, but most of the world is comprised of hunter-gatherer, nomadic, simple farming, or complex farming societies

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d070CivilizationsEarly.html[11/3/2014 5:18:29 PM] Distribution of social and techn

Distribution of social and technological systems in 1000 BCE

Agriculture enabled expansion of farming communities either through spread of the methods or by conquest (probably mainly by conquest!) It led to the establishment of larger communities and eventually kingdoms and civilizations in what is now China, India, Iran, Egypt and Mexico.

Why in those places? 1.Spread of agricultural technology and crops was easiest in an East-West direction since the major land masses are arranged in that direction and:

2. There are barriers in the North-South direction such as mountains, the Central American forest and the Saharan

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d070CivilizationsEarly.html[11/3/2014 5:18:29 PM] Distribution of social and techn

desert

Distribution of social and technological systems in 500 BCE

More state societies emerge in India and China. Empires develop in the Middle East

Distribution of social and technological systems in 200 BCE

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d070CivilizationsEarly.html[11/3/2014 5:18:29 PM] Distribution of social and techn

Then: More Empires develop in Rome, Greece, India and China. More state societies develop.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d070CivilizationsEarly.html[11/3/2014 5:18:29 PM] Barriers affecting Empires

Empires - General Historical Context

For a large scale economic, social and cultural unit like an Empire to develop, there are some obvious criteria:

1. A population large enough and producing enough excess food to

sustain non-agricultural workers an education system to produce skilled workers and bureaucrats a concentration of artisans and bureaucrats in cities and a ruling class sufficiently powerful to impose order and organization in some manner

2. Some kind of armed force to protect the Empire against invaders and/or internal rebellion

3. A succession program for the rulers to prevent too much competition for the ruling positions

Interesting early examples of Empires are those of China and Mongolia.

They had different ways of establishing and maintaining their Empire - the Mongolians under Kublai and Genghis Khan rapidly expanded by force of arms with superior fighting strategy and tactics - their succession was by a meeting of the leaders in their capital city - this saved Europe when the conquering army off Genghis Khan had to return to Mongolia for those succession meetings just before they finished their conquests. Nothing had stopped them until that point.

The Chinese Empires were based on a well-organized bureaucracy (which is why top civil servants today are often called "mandarins") and either negotiation or treaties between regions,. Some actually used water as a weapon against rebellious provinces; in times a water shortages, they cut off rebellious provinces and gave the water to loyal ones - a very powerful incentive to stay loyal. External threats were dealt with by a large armed force, but even if that failed, the invaders were often assimilated into Chinese culture and society.

For an animated view of the rise and fall of civilizations and empires from 1 to 900 CE - Right-click this link and "Open in new window" It is a very large map of the world that cycles through the period from 1 to 900 CE - you can enlarge or decrease the size of the map by zooming your browser and then move around it by using the page "sliders"

Derived and modified from: http://commons.wikimedia.org/wiki/ (Internet Access Required)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d080Empires.html[11/3/2014 5:18:29 PM] Barriers affecting Empires

Barriers affecting Empires

Physical barriers played a large role in allowing and preventing the spread of crops, technologies and social institutions in early history. Travel and communications was very difficult in a North-South direction in Africa, South-East Asia and Australia and in South America due to deserts, large ocean expanses, small islands, mountain ranges and other difficult terrain. It was easier in an East-West direction between Asia, the Middle East and Europe by overland routes with many intermediate stopping places. The result was that:

· Civilizations that developed early on the Eurasian continent gradually came into contact with each other and transferred technology and institutional arrangements.

· Europe had no native crops and did not develop an early civilization but was able to “import” agriculture, crops and technologies from the others (Iran, Egypt and China) since movement was easy in that East-West direction.

· The kingdoms of Sub-Saharan Africa were involved to a very limited extent

· The civilizations in the American continent (Mayans, Incas and Aztecs) were isolated from Eurasia and also largely from each other

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d090Barriers.html[11/3/2014 5:18:29 PM] The Fertile Crescent – General H

The Fertile Crescent – General Historical Context

The Fertile Crescent is regarded as the birthplace of agriculture, urbanization, writing, trade, science, history and organized religion and was first populated c.10,000 BCE (Before Current Era) when agriculture and the domestication of animals began in the region. By 9,000 BCE the cultivation of wild grains and cereals was wide-spread and, by 5000 BCE, irrigation of agricultural crops was fully developed. By 4500 BCE the cultivation of wool-bearing sheep was practiced widely. The first cities began around 4300 BCE and cultivation of wheat and grains was practiced. The unusually fertile soil of the region encouraged the cultivation of wheat as well as rye, barley and From 3400 BC, the priests (who were also the rulers of the cities) were responsible for the distribution of food and the careful monitoring of surplus for trade.

By 2300 BCE, soap was produced from tallow and ash and was in wide use. Attention to one’s person in terms of hygiene was stressed in that human beings were thought to have been created as help-mates to the gods and so should make themselves presentable in the performance of their duties (this was especially so for the Priestly Class). By 2000 BCE, Babylon controlled the Fertile Crescent and the region saw advances in law (Hammurabi’s famous code) literature (The Epic of Gilgamesh, among other works) religion (the development of the Babylonian pantheon of the gods) science and math. From 1900-1400 BCE trade with Europe, Egypt, Phoenicia and the Indian sub-continent was flourishing, resulting in the spread of literacy, culture and religion between these regions.

The region changed hands many times through the ages. By 600 BCE the Assyrians controlled the Fertile Crescent and, by 580, the Neo-Babylonian Chaldean Empire under Nebuchadnezzar II ruled the region. In 539 BCE Babylon fell to the Cyrus the Great after the Battle of Opis and the lands fell under the control of the Achaemenid Empire (also known as The First Persian Empire). Alexander the Great invaded the area in 334 BCE and, after him, it was ruled by the Parthians until the coming of Rome in 116 CE. After the short-lived Roman annexation and occupation, the region was conquered by the Sassanid Persians (c. 226 CE) and, finally, by the Arabian Muslims in the 7th century CE.

By then, the knowledge from the cities which grew up beside the Tigris and Euphrates Rivers had long been disseminated throughout the ancient world but the cities themselves were mostly in ruins through the destruction caused by the many military conquests in the region as well as natural causes such as earthquakes and fire. Over-use of the land and urbanization also resulted in the decline and eventual abandonment of the cities. Eridu, considered by the early Mesopotamians to be the first city on earth, built and inhabited by the gods, had been abandoned since 600 BCE, Uruk, the city of Gilgamesh, since 200 CE and Babylon, the city which gave writing, law and culture to the world was a vacant ruin.

Modified from Wikipedia

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d091FertileCrescent.html[11/3/2014 5:18:30 PM] Ancient Chinese Dynasties

Ancient Chinese Dynasties - General Historical Context

"Territories of Dynasties in China" by Ian Kiu - Zhou Dynasty 1000 B.C. from "The Chou Dynasty, 11th-9th Centuries B.C."Warring States 350 B.C. from "The Contending States- Boundaries of 350 B.C."Han Dynasty 100 B.C. from "Economic Development under the Earlier Han Dynasty, ca. 100 B.C."Sui Dynasty 581 A.D. from "The Sui Dynasty, 581-618 A.D."Tong Dynasty 700 A.D. from "The T'ang Dynasty, 618-906 A.D.-Boundaries of 700 A.D."Albert Herrmann (1935). History and Commercial Atlas of China. Harvard University Press.. Licensed under Creative Commons Attribution-Share Alike 3.0 via Wikimedia Commons - http://commons.wikimedia.org/wiki/File:Territories_of_Dynasties_in_China.gif#mediaviewer/File:Territories_of_Dynasties_in_China.gif

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d092china.html[11/3/2014 5:18:30 PM] Ancient Chinese Dynasties

Extra: Click Image for a PowerPoint slideshow summarizing the Chinese Dynasties (on CD)

Extra: If you have difficulties with PowerPoint, the file is available here as an Adobe Acrobat Reader PDF file on the CD

Summary:

China is one of the areas where civilization developed earliest. It has a recorded history of nearly 5,000 years.

More than a million years ago, primitive human beings lived on the land now called China. About 400,000 to 500,000 years ago, the Peking Man, a primitive man that lived in Zhoukoudian southwest of Beijing, was able to walk with the body erect, to make and use simple tools, and use fire. Six to seven thousand years ago, the people living in the Yellow River valley supported themselves primarily with agriculture, while also raising livestock. More than 3,000 years ago these people began smelting bronze and using ironware.

In China, slave society began around the 21st century B.C. Over the next 1,700 years, agriculture and animal husbandry developed greatly and the skills of silkworm-raising, raw-silk reeling and silk-weaving spread widely. Bronze smelting and casting skills reached a relatively high level, and iron smelting became increasingly sophisticated. The Chinese culture flourished, as a great number of thinkers and philosophers emerged, most famously Confucius.

In 221 B.C., Qin Shi Huang, the first emperor of the Qin Dynasty, established a centralized, unified, multi-national feudal state. This period of feudal society continued until after the Opium War in 1840. During these 2,000 years, China's economy and culture continued to develop, bequeathing a rich heritage of science and technology, literature and the arts. The four great inventions of ancient China - paper-making, printing, the compass and gunpowder - have proved an enormous contribution to world civilization.

Chinese civilization peaked at Tang Dynasty (618-907) when Tang people traded with people all over the world. This is why Chinese residing overseas often call themselves Tang Ren, or the People of Tang.

In 1840, anxious to continue its opium trade in China, Britain started the Opium War against China. After the war, the big foreign powers forcibly occupied "concessions" and divided China into "spheres of influence"; thus, China was transformed into a semi- colonial, semi-feudal society.

In 1911, the bourgeois democratic revolution (the Xinhai Revolution) led by Sun Yat-sen abolished the feudal monarchy, and established the Republic of China, therefore starting the modern history of China.

In 1949, Chinese Communist Party established the People's Republic of China, driving Kumingtang Party to Taiwan Island.

From: http://polaris.gseis.ucla.edu/yanglu/ECC_HISTORY_SUMMARY.htm (Internet Access Required)

Extra - A very detailed timeline is available at http://en.wikipedia.org/wiki/Timeline_of_Chinese_history (Internet Access Required)

Extra - Another good, short history is at http://condensedchina.com/index.html (Internet Access Required)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d092china.html[11/3/2014 5:18:30 PM] The Indus Valley Civilization -

The Indus Valley Civilization - 3300–1300 BCE - General Historical Context

India. Flourishing around the Indus River basin, the civilization extended east into the Ghaggar-Hakra River valley and the upper reaches Ganges-Yamuna Doab; it extended west to the Makran coast of Balochistan, north to northeastern Afghanistan and south to Daimabad in Maharashtra. The civilization was spread over some 1,260,000 km², making it the largest known ancient civilization.

The Indus Valley is one of the world's earliest urban civilizations, along with its contemporaries, Mesopotamia and Ancient Egypt. At its peak, the Indus Civilization may have had a population of well over five million. Inhabitants of the ancient Indus river valley developed new techniques in handicraft (carnelian products, seal carving) and metallurgy (copper, bronze, lead, and tin). The civilization is noted for its cities built of brick, roadside drainage system, and multistoried houses.

The Indus Valley Civilization is also known as the Harappan Civilization, as the first of its cities to be unearthed was located at Harappa. There were earlier and later cultures, often called Early Harappan and Late Harappan, in the same area of the Harappan Civilization. The Harappan civilisation is sometimes called the Mature Harappan culture to distinguish it from these cultures. Over 1,056 cities and settlements have been found, out of which 96 have been excavated, mainly in the general region of the Indus and Ghaggar-Hakra river and its tributaries. Among the settlements were the major urban centres of Harappa, Lothal, Mohenjo-daro (UNESCO World Heritage Site), Dholavira, Kalibanga, and Rakhigarhi.

Modified from Wikipedia

Extra: Documentary Video "Masters of the River" - from http://dharma-documentaries.net/the-indus-valley-the-masters-of- the-river (Internet Access Required)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d093Indus.html[11/3/2014 5:18:30 PM] Egypt – General Historical Conte

Egypt – General Historical Context People began to settle in the Nile valley in about 7000 B.C.. They farmed the land, kept animals, and built permanent homes on the banks of the Nile. Since early history, civilization in Egypt has been closely linked with the annual flooding of the Nile River. Daily life in ancient Egypt revolved around the Nile and the fertile land along its banks. The yearly flooding of the Nile enriched the soil and brought good harvests and wealth to the land. The ancient Egyptians thought of Egypt as being divided into two types of land, the 'black land' and the 'red land'.

The 'black land' was the fertile land on the banks of the Nile. The ancient Egyptians used this land for growing their crops. This was the only land in ancient Egypt that could be farmed because a layer of rich, black silt was deposited there every year after the Nile flooded.

The 'red land' was the barren desert that protected Egypt on two sides. These deserts separated ancient Egypt from neighbouring countries and invading armies. They also provided the ancient Egyptians with a source for precious metals and semi-precious stones.

Narmer (also known as Menes) was the first Egyptian pharaoh to conquer and rule over Upper and Lower Egypt. (3100 BCE)

The first stone pyramid built in ancient Egypt was the 'Step Pyramid'. The Step Pyramid was built at Saqqara for the

pharaoh Djoser. It was made by building several 'steps' or layers of stone on top of each other.

In about 2200 B.C. the government in ancient Egypt collapsed and many people fought to become the ruler of ancient Egypt. For about 150 years, Upper and Lower Egypt had different rulers. Ahmose was a pharaoh who ruled ancient Egypt from 1550 B.C. to 1525 B.C.. In about 1550, Ahmose became pharaoh of Upper and Lower Egypt. The Assyrians came from Mesopotamia. They conquered Egypt in 669 B.C., and controlled the country until 525 B.C The Persians came from the Near East. They conquered Egypt in 525 B.C. and controlled the country until 332 B.C. file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d095Egypt.html[11/3/2014 5:18:30 PM] Egypt – General Historical Conte

Alexander the Great (352-323 B.C.) came from Macedonia. Alexander had conquered much of Greece and the Levant by the time he was about 20 years old. In 332 B.C. Alexander conquered Egypt.

He founded the city of Alexandria on the Mediterranean coast, then left Egypt to continue his battles in the Near East. Alexander conquered territories as far east as India. However, in 323 B.C. he died of a fever.

In A.D. 642 Egypt was conquered by Arabs who came from lands in the east.

1517 – The Ottaman Turks ruled Egypt In the late eighteenth century, the French ruler, Napoleon Bonaparte invaded Egypt. In 1798, he fought against the rulers of Egypt called the Mamelukes. Napoleon and the Mamelukes fought a major battle near the pyramids of Giza.

A dam built in the 1960s to control the annual flooding of the Nile, and to create a reservoir. The water flowing from the Nile sources collects south of the dam forming Lake Nasser. Lake Nasser covers much of the area that was ancient Nubia.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d095Egypt.html[11/3/2014 5:18:30 PM] Egypt – General Historical Conte

Narmer (also known as Menes) was the first Egyptian pharaoh to conquer and rule over Upper and Lower Egypt. (3100 BCE)

The first stone pyramid built in ancient Egypt was the 'Step Pyramid'. The Step Pyramid was built at Saqqara for the

pharaoh Djoser. It was made by building several 'steps' or layers of stone on top of each other.

In about 2200 B.C. the government in ancient Egypt collapsed and many people fought to become the ruler of ancient Egypt. For about 150 years, Upper and Lower Egypt had different rulers. Ahmose was a pharaoh who ruled ancient Egypt from 1550 B.C. to 1525 B.C.. In about 1550, Ahmose became pharaoh of Upper and Lower Egypt. The Assyrians came from Mesopotamia. They conquered Egypt in 669 B.C., and controlled the country until 525 B.C The Persians came from the Near East. They conquered Egypt in 525 B.C. and controlled the country until 332 B.C. file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d095Eygypt.html[11/3/2014 5:18:30 PM] Egypt – General Historical Conte

Alexander the Great (352-323 B.C.) came from Macedonia. Alexander had conquered much of Greece and the Levant by the time he was about 20 years old. In 332 B.C. Alexander conquered Egypt.

In A.D. 642 Egypt was conquered by Arabs who came from lands in the east.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d095Eygypt.html[11/3/2014 5:18:30 PM] Greece – General Historical Cont

Greece – General Historical Context

The history of Greece starts in Neolithic times with some small settlements, prroceeds through the Bronze Age when Aegean civilization is a general term for the Bronze Age civilizations of Greece around the Aegean Sea. There are three distinct but communicating and interacting geographic regions covered by this term:Crete, the Cyclades and the Greek mainland. Crete is associated with the Minoan civilization from the Early Bronze Age. The collapse of the Mycenaean civilization coincided with the fall of several other large empires in the near east, most notably the Hittite and the Egyptian. The Greek Dark Ages (ca. 1100 BC–800 BC) refers to the period of Greek history from the presumed Dorian invasion and end of the Mycenaean civilization in the 11th century BC to the rise of the first Greek city-states in the 9th century BC and the epics of Homer and earliest writings in alphabetic Greek in the 8th century BC. Ancient Greece was an ancient civilization belonging to a period of Greek history that lasted from the Archaic period of the 8th to 6th centuries BC to the end of antiquity (ca. 600 AD). In common usage it refers to all Greek history before the Roman Empire, but historians use the term more precisely. Some writers include the periods of the Minoan and Mycenaean civilizations, while others argue that these civilizations were so different from later Greek cultures that they should be classed separately. Traditionally, the Ancient Greek period was taken to begin with the date of the first Olympic Games in 776 BC, but most historians now extend the term back to about 1000 BC. In Ancient Greece the basic unit of politics in Ancient Greece was the polis, sometimes translated as city-state. "Politics" literally means "the things of the polis". Each city was independent, at least in theory. Some cities might be subordinate to others (a colony traditionally deferred to its mother city), some might have had governments wholly dependent upon others (the Thirty Tyrants in Athens was imposed by Sparta following the Peloponnesian War), but the titularly supreme power in each city was located within that city. This meant that when Greece went to war (e.g., against the Persian Empire), it took the form of an alliance going to war. It also gave ample opportunity for wars within Greece between different cities. The traditional date for the end of the Ancient Greek period is the death of Alexander the Great in 323 BC. Ancient Greece is considered by most historians to be the foundational culture of Western Civilization. Greek culture was a powerful influence in the Roman Empire, which carried a version of it to many parts of Europe. The Hellenistic period of Greek history begins with the death of Alexander the Great in 323 BC and ends with the annexation of the Greek peninsula and islands by Rome in 146 BC. Although the establishment of Roman rule did not break the continuity of Hellenistic society and culture, which remained essentially unchanged until the advent of Christianity, it did mark the end of Greek political independence. During the Hellenistic period the importance of "Greece proper" (that is, the territory of modern Greece) within the Greek-speaking world declined sharply. The great centres of Hellenistic culture were Alexandria and Antioch, capitals of Ptolemaic Egypt and Seleucid Syria.

(Modified from Wikipedia)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d097Greece.html[11/3/2014 5:18:31 PM] Rome - General Historical Conte

Rome - General Historical Context

600 BC The Etruscans establish cities from northern to central Italy 282 BC 282-272: War with Pyrrhus 264 BC 264-241: War with Carthage (First Punic War) 218 BC Hannibal invades Italy 135BC First Servile War prompted by slave revolts 73 BC Slave uprising led by the gladiator called Spartacus 64 BC Pompey captures Jerusalem 45 BC Julius Caesar defeats Pompey to become the first dictator of Rome 44 BC Julius Caesar assassinated 44 BC The Triumvirate of Marc Antony, Lepidus, and Octavian (later known as Caesar Augustus) become the rulers of Rome 31 BC Antony and Cleopatra are defeated by Octavian 27 BC Octavian becomes Caesar Augustus, the first Roman emperor until 14AD 14AD Death of Augustus and Tiberius, stepson of Caesar Augustus, becomes emperor until 37AD 37 Gaius (Caligula) crowned Emperor 41 Caligula is killed and Claudius proclaimed Emperor 54 Emperor Claudius is murdered and Nero is proclaimed Emperor 64 Fire destroyed much of Rome - the Christians are blamed for the destruction 68 The death of Nero ended the infamous Julio-Claudian dynasty 75 The Roman emperors start to build the Coliseum in Rome as a place of gladiatorial combat 180 Commodus succeeds his father Marcus Aurelius and gains imperial power 305 Constantine becomes the first Christian emperor 380 Christianity is declared the sole religion of the Roman Empire by Theodosius I 410 The Visigoths, led by Alaric, sack Rome heralding the total decline of the Roman Empire 455 The Vandals, led by Gaiseric, sack Rome 476 The last Roman Emperor was Romulus Augustulus who was defeated by Odoacer who was a German Goth

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d098Rome.html[11/3/2014 5:18:31 PM] Hydrologic Cycle - The Water Cyc

Hydrologic Cycle - The Water Cycle

The water cycle describes the existence and movement of water on, in, and above the Earth. Earth's water is always in movement and is always changing states, from liquid to vapor to ice and back again. The water cycle has been working for billions of years and all life on Earth depends on it continuing to work.

The water cycle has no starting point, but most water is in the world's oceans. The sun, which drives the water cycle, heats water in the oceans. Some of it evaporates as vapor into the air; a relatively smaller amount of moisture is added as ice and snow sublimate directly from the solid state into vapor. Rising air currents take the vapor up into the atmosphere, along with water from evapotranspiration, which is water transpired from plants and evaporated from the soil. The vapor rises into the air where cooler temperatures cause it to condense into clouds.

Air currents move clouds around the globe, and cloud particles collide, grow, and fall out of the sky as precipitation. Some precipitation falls as snow and can accumulate as ice caps and glaciers, which can store frozen water for thousands of years. Snowpacks in warmer climates often thaw and melt when spring arrives, and the melted water flows overland as snowmelt. Most precipitation falls back into the oceans or onto land, where, due to gravity, the precipitation flows over the ground as surface runoff. A portion of runoff enters rivers in valleys in the landscape, with streamflow moving water towards the oceans. Runoff, and groundwater seepage accumulate and are stored as freshwater in lakes.

Not all runoff flows into rivers, though. Much of it soaks into the ground as infiltration. Some of the water infiltrates into the ground and replenishes aquifers (saturated subsurface rock), which store huge amounts of freshwater for long periods of time. Some infiltration stays close to the land surface and can seep back into surface-water bodies (and the ocean) as groundwater discharge, and some groundwater finds openings in the land surface and emerges as freshwater springs. Yet more groundwater is absorbed by plant roots to end up as evapotranspiration from the leaves.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d100WaterCycleTitle.html[11/3/2014 5:18:31 PM] Main components of the water cyc

Main components of the water cycle - Part 1

Water storage in oceans:

The water cycle sounds like it is describing how water moves above, on, and through the Earth ... and it does. But, in fact, much more water is in storage; for long periods of time than is actually moving through the cycle. The storehouses for the vast majority of all water on Earth are the oceans. It is estimated that of the 332,600,000 cubic miles (mi3) (1,386,000,000 cubic kilometers (km3)) of the world's water supply, about 321,000,000 mi3 (1,338,000,000 km3) is stored in oceans. That is about 96.5 percent. It is also estimated that the oceans supply about 90 percent of the evaporated water that goes into the water cycle.

During colder climatic periods more ice caps and glaciers form, and enough of the global water supply accumulates as ice to lessen the amounts in other parts of the water cycle. The reverse is true during warm periods. During the last ice age glaciers covered almost one-third of Earth's land mass, with the result being that the oceans were about 400 feet (122 meters) lower than today. During the last global "warm spell," about 125,000 years ago, the seas were about 18 feet (5.5. meters) higher than they are now. About three million years ago the oceans could have been up to 165 feet (50 meters) higher.

Oceans in movement

You might think that the water in the oceans moves around because of waves, which are driven by winds. But, actually, there are currents and "rivers" in the oceans that move massive amounts of water around the world. These movements have a great deal of influence on the water cycle. The Kuroshio Current, off the shores of Japan, is the largest current. It can travel between 25 and 75 miles (40 and 121 kilometers) a day, 1-3 miles (1.4-4.8 kilometers) per hour, and extends some 3,300 feet (1,000 meters) deep. The Gulf Stream is a well known stream of warm water in the Atlantic Ocean, moving water from the Gulf of Mexico across the Atlantic Ocean towards Great Britain. At a speed of 60 miles (97 kilometers) per day, the Gulf stream moves 100 times as much water as all the rivers on Earth. Coming from warm climates, the Gulf Stream moves warmer water to the North Atlantic.

Evaporation:

Evaporation is the process by which water changes from a liquid to a gas or vapor. Evaporation is the primary pathway that water moves from the liquid state back into the water cycle as atmospheric water vapor. Studies have shown that the oceans, seas, lakes, and rivers provide nearly 90 percent of the moisture in our atmosphere via evaporation, with the remaining 10 percent being contributed by plan Heat (energy) is necessary for evaporation to occur. Energy is used to break the bonds that hold water molecules together, which is why water easily evaporates at the boiling point (212° F, 100° C) but evaporates much more slowly at the freezing point. Net evaporation occurs when the rate of evaporation exceeds the rate of condensation. A state of saturation exists when these two process rates are equal, at which point, the relative humidity of the air is 100 percent. Condensation, the opposite of evaporation, occurs when saturated air is cooled below the dew point (the temperature to which air must be cooled at a constant pressure for it to become fully saturated with water), such as on the outside of a glass of ice water. In fact, the process of evaporation removes heat from the environment, which is why water evaporating from your skin cools you.

Evaporation drives the water cycle

Evaporation from the oceans is the primary mechanism supporting the surface-to-atmosphere portion of the water cycle. After all, the large surface area of the oceans (over 70 percent of the Earth's surface is covered by the oceans) provides the opportunity for such large-scale evaporation to occur. On a global scale, the amount of water evaporating is about the same as the amount of water delivered to the Earth as precipitation. This does vary geographically, though. Evaporation is more prevalent over the oceans than precipitation, while over the land precipitation routinely exceeds evaporation. Most of the water that evaporates from the oceans falls back into the oceans as precipitation. Only about 10 percent of the water evaporated from the oceans is transported over land and falls as precipitation. Once evaporated, a water molecule spends about 10 days in the air

Sublimation:

Sublimation describes the process of snow and ice changing into water vapor without first melting into water. Sublimation is a common way for snow to disappear in certain climates.

It is not easy to actually see sublimation happen, at least not with ice. One way to see the results of sublimation is to hang a wet shirt outside on a below-freezing day. Eventually the ice in the shirt will disappear. Actually, the best way to visualize sublimation is to not use water at all, but to use carbon dioxide instead, as this picture shows."Dry ice" is solid, frozen carbon dioxide, which sublimates, or turns to gas, at the temperature -78.5 °C (-109.3°F). The fog you see in the picture is a mixture of cold carbon

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d105WaterCycle1.html[11/3/2014 5:18:31 PM] Main components of the water cyc

dioxide gas and cold, humid air, created as the dry ice sublimates.

Sublimation occurs more readily when certain weather conditions are present, such as low relative humidity and dry winds. It also occurs more at higher altitudes, where the air pressure is less than at lower altitudes. Energy, such as strong sunlight, is also needed. If I was to pick one place on Earth where sublimation happens a lot, I might choose the south side of Mt. Everest. Low temperatures, strong winds, intense sunlight, very low air pressure - just what is needed for sublimation to occur.

Evapotranspiration:

Although some definitions of evapotranspiration include evaporation from surface-water bodies, such as lakes and even the ocean, on this Web site, evapotranspiration is defined as the water lost to the atmosphere from the ground surface and the transpiration of groundwater by plants through their leaves.

Transpiration:

Plant transpiration is an invisible process;since the water is evaporating from the leaf surfaces, you don't just go out and see the leaves "breathing". During a growing season, a leaf will transpire many times more water than its own weight. A large oak tree can transpire 40,000 gallons (151,000 liters) per year.

The amount of water that plants transpire varies greatly geographically and over time. There are a number of factors that determine transpiration rates:

Temperature Transpiration rates go up as the temperature goes up, especially during the growing season, when the air is warmer.

Relative humidity: As the relative humidity of the air surrounding the plant rises the transpiration rate falls. It is easier for water to evaporate into dryer air than into more saturated air.

Increased movement of the air around a plant will result in a higher transpiration rate. When moisture is lacking, plants can begin to senesce (premature ageing, which can result in leaf loss) and transpire less water.Plants transpire water at different rates. Some plants which grow in arid regions, such as cacti and succulents, conserve precious water by transpiring less water than other plants.

Water storage in the atmosphere

The water cycle is all about storing water and moving water on, in, and above the Earth. Although the atmosphere may not be a great storehouse of water, it is the superhighway used to move water around the globe. There is always water in the atmosphere. Clouds are, of course, the most visible manifestation of atmospheric water, but even clear air contains water; water in particles that are too small to be seen. One estimate of the volume of water in the atmosphere at any one time is about 3,100 cubic miles (mi3) or 12,900 cubic kilometers (km3). That may sound like a lot, but it is only about 0.001 percent of the total Earth's water volume. If all of the water in the atmosphere rained down at once, it would only cover the ground to a depth of 2.5 centimeters, about 1 inch.

Condensation:

Condensation is the process in which water vapor in the air is changed into liquid water. Condensation is crucial to the water cycle because it is responsible for the formation of clouds. These clouds may produce precipitation, which is the primary route for water to return to the Earth's surface within the water cycle. Condensation is the opposite of evaporation.

You don't have to look at something as far away as a cloud to notice condensation, though. Condensation is responsible for ground-level fog, for your glasses fogging up when you go from a cold room to the outdoors on a hot, humid day, for the water that drips off the outside of your glass of iced tea, and for the water on the inside of your home windows on a cold day.

Condensation in the air

Even though clouds are absent in a crystal clear blue sky, water is still present in the form of water vapor and droplets which are too small to be seen. Depending on meteorological conditions, water molecules will combine with tiny particles of dust, salt, and smoke in the air to form cloud droplets, which grow and develop into clouds, a form of water we can see. Cloud droplets can vary greatly in size, from 10 microns (millionths of a meter) to 1 millimeter (mm), and even as large as 5 mm. This process occurs higher in the sky where the air is cooler and more condensation occurs relative to evaporation. As water droplets combine (also known as coalescence) with each other, and grow in size, clouds not only develop, but precipitation may also occur. Precipitation is essentially water cloud in its liquid or solid form falling form the base of a cloud. This seems to happen too often during picnics or

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d105WaterCycle1.html[11/3/2014 5:18:31 PM] Main components of the water cyc

when large groups of people gather at swimming pools.

As we said, clouds form in the atmosphere because air containing water vapor rises and cools. The key to this process is that air near the Earth's surface is warmed by solar radiation. But, do you know why the atmosphere cools above the Earth's surface? Generally, air pressure, is the reason. Air has mass (and, because of gravity on Earth, weight) and at sea level the weight of a column of air pressing down on your head is about 14 ½ pounds (6.6 kilograms) per square inch. The pressure (weight), called barometric pressure, that results is a consequence of the density of the air above. At higher altitudes, there is less air above, and, thus, less air pressure pressing down. The barometric pressure is lower, and lower barometric pressure is associated with fewer molecules per unit volume. Therefore, the air at higher altitudes is less dense. Since fewer air molecules exist in a certain volume of air, there are fewer molecules colliding with each other, and as a result, there will be less heat produced. This means cooler air. Do you find this confusing? Just think, clouds form all day long without having to understand any of this.

Precipitation:

Precipitation is water released from clouds in the form of rain, freezing rain, sleet, snow, or hail. It is the primary connection in the water cycle that provides for the delivery of atmospheric water to the Earth. Most precipitation falls as rain.

The clouds floating overhead contain water vapor and cloud droplets, which are small drops of condensed water. These droplets are way too small to fall as precipitation, but they are large enough to form visible clouds. Water is continually evaporating and condensing in the sky. If you look closely at a cloud you can see some parts disappearing (evaporating) while other parts are growing (condensation). Most of the condensed water in clouds does not fall as precipitation because their fall speed is not large enough to overcome updrafts which support the clouds. For precipitation to happen, first tiny water droplets must condense on even tinier dust, salt, or smoke particles, which act as a nucleus. Water droplets may grow as a result of additional condensation of water vapor when the particles collide. If enough collisions occur to produce a droplet with a fall velocity which exceeds the cloud updraft speed, then it will fall out of the cloud as precipitation. This is not a trivial task since millions of cloud droplets are required to produce a single raindrop.

Precipitation rates vary geographically and over tim. Precipitation does not fall in the same amounts throughout the world, in a country, or even in a city. For example, in Georgia, USA, it rains fairly evenly all during the year, around 40-50 inches (102-127 centimeters (cm)) per year. Summer thunderstorms may deliver an inch or more of rain on one suburb while leaving another area dry a few miles away. But, the rain amount that Georgia gets in one month is often more than Las Vegas, Nevada observes all year. The world's record for average-annual rainfall belongs to Mt. Waialeale, Hawaii, where it averages about 450 inches (1,140 cm) per year. A remarkable 642 inches (1,630 cm) was reported there during one twelve-month period (that's almost 2 inches (5 cm) every day!). Is this the world record for the most rain in a year? No, that was recorded at Cherrapunji, India, where it rained 905 inches (2,300 cm) in 1861. Contrast those excessive precipitation amounts to Arica, Chile, where no rain fell for 14 years

The map below shows average annual precipitation, in millimeters and inches, for the world. The light green areas can be considered "deserts". You might expect the Sahara area in Africa to be a desert, but much of Greenland and Antarctica are deserts.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d105WaterCycle1.html[11/3/2014 5:18:31 PM] Main components of the water cyc

On average, the 48 continental United States receives enough precipitation in one year to cover the land to a depth of 30 inches (0.76 meters).

Ice caps around the world.

The vast majority, almost 90 percent, of Earth's ice mass is in Antarctica, while the Greenland ice cap contains 10 percent of the total global ice-mass. The Greenland ice cap is an interesting part of the water cycle. The ice cap became so large over time (about 600,000 cubic miles (mi3) or 2.5 million cubic kilometers (km3)) because more snow fell than melted. Over the millenia, as the snow got deeper, it compressed and became ice. The ice cap averages about 5,000 feet (1,500 meters) in thickness, but can be as thick as 14,000 feet (4,300 meters). The ice is so heavy that the land below it has been pressed down into the shape of a bowl. In many places, glaciers on Greenland reach to the sea, and one estimate is that as much as 125 mi3 (517 km3) of ice "calves" into the ocean each year;one of Greenland's contributions to the global water cycle. Ocean-bound icebergs travel with the currents, melting along the way. Some icebergs have been seen, in much smaller form, as far south as the island of Bermuda.

Ice and glaciers

The climate, on a global scale, is always changing, although usually not at a rate fast enough for people to notice. There have been many warm periods, such as when the dinosaurs lived (about 100 million years ago) and many cold periods, such as the last ice age of about 20,000 years ago. During the last ice age much of the northern hemisphere was covered in ice and glaciers, and, as this map from the University of Arizona shows, they covered nearly all of Canada, much of northern Asia and Europe, and extended well into the United States.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d105WaterCycle1.html[11/3/2014 5:18:31 PM] Main components of the water cyc

The vast majority, almost 90 percent, of Earth's ice mass is in Antarctica, while the Greenland ice cap contains 10 percent of the total global ice mass. The Greenland ice cap is an interesting part of the water cycle. The ice cap became so large over time (about 600,000 cubic miles (mi3) or 2.5 million cubic kilometers (km3)) because more snow fell than melted. Over the millennia, as the snow got deeper, it compressed and became ice. The ice cap averages about 5,000 feet (1,500 meters) in thickness, but can be as thick as 14,000 feet (4,300 meters). The ice is so heavy that the land below it has been pressed down into the shape of a bowl. In many places, glaciers on Greenland reach to the sea, and one estimate is that as much as 125 mi3 (517 km3) of ice "calves" into the ocean each year—one of Greenland's contributions to the global water cycle. Ocean-bound icebergs travel with the currents, melting along the way. Some icebergs have been seen, in much smaller form, as far south as the island of Bermuda.

Contribution of snowmelt to streamflow

A good way to visualize the contribution of snowmelt to streamflow in rivers is to look at the hydrograph below, which shows daily mean streamflow (average streamflow for each day) for four years for the North Fork American River at North Fork Dam in California. The large peaks in the chart are mainly the result of melting snow, although storms can contribute runoff also. Compare the fact that minimum mean-daily streamflow during March of 2000 was 1,200 cubic feet per second (ft3), while during August streamflows ranged from 55-75 ft3.

Note that runoff from snowmelt varies not only by season but also by year. Compare the high peaks of streamflows for the year 2000 with the much smaller streamflows for 2001. It looks like a major drought hit that area of California in 2001. The lack of water stored as snowpack in the winter can affect the availability of water (for streamflow) in streams the rest of the year. This can have an effect on the amount of water in reservoirs located downstream, which in turn can affect water available for irrigation and the water supply for cities and towns.

Surface runoff

Many people probably have an overly-simplified idea that precipitation falls on the land, flows overland (runoff), and runs into rivers, which then empty into the oceans. That is "overly simplified" because rivers also gain and lose water to the ground. Still, it is true that much of the water in rivers comes directly from runoff from the land surface, which is defined as surface runoff.

When rain hits saturated or impervious ground it begins to flow overland downhill. It is easy to see if it flows down your driveway to the curb and into a storm sewer, but it is harder to notice it flowing overland in a natural setting. During a heavy rain you might notice small rivulets of water flowing downhill. Water will flow along channels as it moves into larger creeks, streams, and rivers. This picture gives a graphic example of how surface runoff (here flowing off a road) enters a small creek. The runoff in this case is flowing over bare soil and is depositing sediment into the river (not good for water quality). The runoff entering this creek is beginning its journey back to the ocean.

As with all aspects of the water cycle, the interaction between precipitation and surface runoff varies according to time and geography. Similar storms occurring in the Amazon jungle and in the desert Southwest of the United States will produce different surface-runoff effects. Surface runoff is affected by both meteorological factors and the physical geology and topography of the land. Only about a third of the precipitation that falls over land runs off into streams and rivers and is returned to the oceans. The other two-thirds is evaporated, transpired, or soaks into groundwater. Surface runoff can also be diverted by humans for their own file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d105WaterCycle1.html[11/3/2014 5:18:31 PM] Main components of the water cyc

uses

The U.S. Geological Survey (USGS) uses the term streamflow to refer to the amount of water flowing in a river.

Amended from the United States Geological Survey web site at http://ga.water.usgs.gov/edu/watercycle.html (Internet bAccess Required)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d105WaterCycle1.html[11/3/2014 5:18:31 PM] Main components of the water cyc

Main components of the water cycle - Continued - Part 2

Importance of rivers

Rivers are invaluable to not only people, but to life everywhere. Not only are rivers a great place for people (and their dogs) to play, but people use river water for drinking-water supplies and irrigation water, to produce electricity, to flush away wastes (hopefully, but not always, treated wastes), to transport merchandise, and to obtain food. Rivers are indeed major aquatic landscapes for all manners of plants and animals. Rivers even help keep the aquifers underground full of water by discharging water downward through their streambeds. And, we've already mentioned that the oceans stay full of water because rivers and runoff continually refreshes them.

Watersheds and rivers

When looking at the location of rivers and also the amount of streamflow in rivers, the key concept to know about is the river's "watershed". What is a watershed? Easy, if you are standing on the ground right now, just look down. You're standing, and everyone is standing, in a watershed. A watershed is the area of land where all of the water that falls in it and drains off of it goes into the same place. Watersheds can be as small as a footprint in the mud or large enough to encompass all the land that drains water into the Mississippi River where it enters the Gulf of Mexico. Smaller watersheds are contained in bigger watersheds. It all depends of the outflow point;all of the land above that drains water that flows to the outflow point is the watershed for that outflow location. Watersheds are important because the streamflow and the water quality of a river are affected by things, human-induced or not, happening in the land area "above" the river-outflow point

Streamflow is always changing, from day to day and even minute to minute. Of course, the main influence on streamflow is precipitation runoff in the watershed. Rainfall causes rivers to rise, and a river can even rise if it only rains very far up in the watershed; remember that water that falls in a watershed will eventually drain by the outflow point. The size of a river is highly dependent on the size of its watershed. Large rivers have watersheds with lots of surface area; small rivers have smaller watersheds. Likewise, different size rivers react differently to storms and rainfall. Large rivers rise and fall slower and at a slower rate than small rivers. In a small watershed, a storm can cause 100 times as much water to flow by each minute as during baseflow periods, but the river will rise and fall possibly in a matter of minutes and hours. Large rivers may take days to rise and fall, and flooding can last for a number of days. After all, it can take days for all the water that fell hundreds of miles upstream to drain past an outflow point.

One part of the water cycle that is obviously esential to all life on Earth is the freshwater existing on the land surface. Just ask your neighbor, a tomato plant, a trout, or that pesky mosquito. Surface water includes the streams (of all sizes, from large rivers to small creeks), ponds, lakes, reservoirs (man-made lakes), and freshwater wetlands. The definition of freshwater is water containing less than 1,000 milligrams per liter of dissolved solids, most often salt.

The amount of water in our rivers and lakes is always changing due to inflows and outflows. Inflows to these water bodies will be from precipitation, overland runoff, ground-water seepage, or tributary inflows. Outflows from lakes and rivers include evaporation and discharge to groundwater. Humans get into the act also, as people make great use of diverted surface water for their needs. So, the amount and location of surface water changes over time and space, whether naturally or with human help. Certainly during the last ice age when glaciers and snowpacks covered much more land surface than today, life on Earth had to adapt to different hydrologic conditions than >those which took place both before and after. And the layout of the landscape certainly was different before and after the last ice age, which influenced the topographical layout of many surface-water bodies today. Glaciers are what made the Great Lakes not only "great," but also such a huge storehouse of freshwater Surface water keeps life going

Water on the land surface really does sustain life, and this is as true today as it was millions of years ago. Dinosaurs held their meetings at the local watering hole 100 million years ago, just as antelopes in Africa do today. And, since groundwater is supplied by the downward percolation of surface water, even aquifers are happy for water on the Earth's surface. You might think that fish living in the saline oceans aren't affected by freshwater, but, without freshwater to replenish the oceans they would eventually evaporate and become too saline for even the fish to survive.

Usable freshwater is relatively scarce and represents only about three percent of all water on Earth and freshwater lakes and swamps account for a mere 0.29 percent of the Earth's freshwater. Twenty percent of all freshwater is in one lake, Lake Baikal in Asia. Another twenty percent is stored in the Great Lakes (Huron, Michigan, and Superior). Rivers hold only about 0.006 percent of total freshwater reserves. You can see that life on Earth survives on what is essentially only a "drop in the bucket" of Earth's total water supply

Groundwater begins as precipitation

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d110WaterCycle2.html[11/3/2014 5:18:32 PM] Main components of the water cyc

Anywhere in the world, a portion of the water that falls as rain and snow infiltrates into the subsurface soil and rock. How much infiltrates depends greatly on a number of factors. Infiltration of precipitation falling on the ice cap of Greenland might be very small, whereas, as this picture of a stream disappearing into a cave in southern Georgia, USA shows, a stream can act as a direct funnel right into groundwater!

Some water that infiltrates will remain in the shallow soil layer, where it will gradually move vertically and horizontally through the soil and subsurface material. Eventually it might enter a stream by seepage into the stream bank. Some of the water may infiltrate deeper, recharging ground-water aquifers. If the aquifers are shallow or porous enough to allow water to move freely through it, people can drill wells into the aquifer and use the water for their purposes. Water may travel long distances or remain in groundwater storage for long periods before returning to the surface or seeping into other water bodies, such as streams and the oceans.

In places where the water table (the top of the saturated zone) is close to the land surface and where the water can move through the aquifer at a high rate, aquifers can be replenished artificially

Groundwater storage:

Large amounts of water are stored in the ground. The water is still moving, possibly very slowly, and it is a part of the water cycle. Most of the water in the ground comes from precipitation that infiltrates downward from the land surface. The upper layer of the soil is the unsaturated zone, where water is present in varying amounts that change over time, but does not saturate the soil. Below this layer is the saturated zone, where all of the pores, cracks, and spaces between rock particles are saturated with water. The term groundwater is used to describe this area. Another term for groundwater is "aquifer," although this term is usually used to describe water-bearing formations capable of yielding enough water to supply peoples' uses. Aquifers are a huge storehouse of Earth's water and people all over the world depend on groundwater in their daily lives.

At a certain depth the ground, if it is permeable enough to hold water, the soil is saturated with water. The top of the pool of water in this hole is the water table.

To access freshwater, people have to drill wells deep enough to tap into an aquifer. The well might have to be dozens or thousands of feet deep. But the concept is the same - access the water in the saturated zone where the voids in the rock are full of water.

You see water all around you every day as lakes, rivers, ice, rain and snow. There are also vast amounts of water that are unseen; water existing in the ground. And even though groundwater is unseen, it is moving below your feet right now. As part of the water cycle, groundwater is a major contributor to flow in many streams and rivers and has a strong influence on river and wetland habitats for plants and animals. People have been using groundwater for thousands of years and continue to use it today, largely for drinking water and irrigation. Life on Earth depends on groundwater just as it does on surface water.

Groundwater flows underground

Some of the precipitation that falls onto the land infiltrates into the ground to become groundwater. Once in the ground, some of this water travels close to the land surface and emerges very quickly as discharge into streambeds, but, because of gravity, much of it continues to sink deeper into the ground. If the water meets the water table (below which the soil is saturated), it can move both vertically and horizontally. Water moving downward can also meet more dense and water-resistant non-porous rock and soil, which causes it to flow in a more horizontal fashion, generally towards streams, the ocean, or deeper into the ground.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d110WaterCycle2.html[11/3/2014 5:18:32 PM] Main components of the water cyc

As this diagram shows, the direction and speed of ground-water movement is determined by the various characteristics of aquifers and confining layers (which water has a difficult time penetrating) in the ground. Water moving below ground depends on the permeability (how easy or difficult it is for water to move) and on the porosity (the amount of open space in the material) of the subsurface rock. If the rock has characteristics that allow water to move relatively freely through it, then groundwater can move significant distances in a number of days. But groundwater can also sink into deep aquifers where it takes thousands of years to move back into the environment, or even go into deep ground-water storage, where it might stay for much longer periods.

Springs

A spring is a water resource formed when the side of a hill, a valley bottom or other excavation intersects a flowing body of groundwater at or below the local water table. A spring is the result of an aquifer being filled to the point that the water overflows onto the land surface. They range in size from intermittent seeps, which flow only after much rain, to huge pools with a flow of hundreds of millions of liters per day.

Springs may be formed in any sort of rock, but are more prevalent in limestone and dolomite, which fracture easily and can be dissolved by rainfall that becomes weakly acidic. As the rock dissolves and fractures, spaces can form that allow water to flow. If the flow is horizontal, it can reach the land surface, resulting in a spring.

Water from springs usually is remarkably clear. Water from some springs, however, may be "tea-colored." In Florida, many surface waters contain natural tannic acids from organic material in subsurface rocks, and the color from these streams can appear in springs. If surface water enters the aquifer near a spring, the water can move quickly through the aquifer and discharge at the spring vent. The discharge of highly colored water from springs can indicate that water is flowing quickly through large channels within the aquifer without being filtered through the limestone.

Thermal springs are ordinary springs except that the water is warm and, in some places, hot, such as in the bubbling mud springs in Yellowstone National Park, Wyoming. Many thermal springs occur in regions of recent volcanic activity and are fed by water heated by contact with hot rocks far below the surface. Even where there has been no recent volcanic action, rocks become warmer with increasing depth. In such areas water may migrate slowly to considerable depth, warming as it descends through rocks deep in the Earth. If it then reaches a large crevice that offers a path of less resistance, it may rise more quickly than it descended. Water that does not have time to cool before it emerges forms a thermal spring.

Amended from the United States Geological Survey web site at http://ga.water.usgs.gov/edu/watercycle.html (Internet bAccess Required)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d110WaterCycle2.html[11/3/2014 5:18:32 PM] Distribution of Water on the Ear

Distribution of Water on the Earth

The vast majority (96.5%) of the water on Earth is in the oceans as salt water. Unless desalinated with high energy expenditure, this is not available for human consumption.

Saline groundwater and saline lakes (both also unavailable for direct human consumption) comprises 0.93% and 0.07%, respectively.

Freshwater comprises only 2.5% of the water on Earth - but 68.6% of this is in the ice caps and glaciers and 30.1% is in the form of groundwater, leaving only 1.3% of the freshwater on Earth easily available as surface and other freshwater sources for human consumption and use.

Of this 1.3%, 73.1% is in the form of ice and snow, 20.1% is in lakes, 0.46% is in rivers, 2.53% is in swamps and marshes, 3,52% is soil moisture, 0.22% is atmospheric water and 0.22% is in organisms (biological water).

One estimate of global water distribution

Water source Water volume, in Water volume, in Percent Percent cubic miles cubic kilometers of of total water

Oceans, Seas, & Bays 321,000,000 1,338,000,000 -- 96.5

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d115WaterDistribution.html[11/3/2014 5:18:32 PM] Distribution of Water on the Ear

Ice caps, Glaciers, & 5,773,000 24,064,000 68.6 1.74 Permanent Snow

Groundwater 5,614,000 23,400,000 -- 1.7

Fresh 2,526,000 10,530,000 30.1 0.76

Saline 3,088,000 12,870,000 -- 0.93

Soil Moisture 3,959 16,500 0.05 0.001

Ground Ice & 71,970 300,000 0.86 0.022 Permafrost

Lakes 42,320 176,400 -- 0.013

Fresh 21,830 91,000 0.26 0.007

Saline 20,490 85,400 -- 0.007

Atmosphere 3,095 12,900 0.04 0.001

Swamp Water 2,752 11,470 0.03 0.0008

Rivers 509 2,120 0.006 0.0002

Biological Water 269 1,120 0.003 0.0001

Source: Igor Shiklomanov's chapter "World fresh water resources" in Peter H. Gleick (editor), 1993, Water in Crisis: A Guide to the World's Fresh Water Resources (Oxford University Press, New York).

Approximate residence time of water found in various reservoirs.

Approximate Residence Reservoir Time

Glaciers 40 years

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d115WaterDistribution.html[11/3/2014 5:18:32 PM] Distribution of Water on the Ear

Seasonal Snow Cover 0.4 years

Soil Moisture 0.2 years

Groundwater: Shallow 200 years

Groundwater: Deep 10,000 years

Lakes 100 years

Rivers 0.04 years

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d115WaterDistribution.html[11/3/2014 5:18:32 PM] The Earth

The Earth's Atmosphere and Climate

Click blue Start button to start animation

Urgent: As of May 2014, Google has blocked the Windows Media plugin and so Chrome (after Version 33) will NOT play any video files of this type. There is a workaround available - downloading and installing the VLC plugin to Chrome will allow playback. Microsoft Internet Explorer and Firebox will both play the videos without any plug-in.

Earth Surface Temperature Fires

Water Vapour Vegetation Index

DETAILS

LAND SURFACE TEMPERATURE: is how hot the “surface” of the Earth would feel to the touch in a particular location. From a satellite’s point of view, the “surface” is whatever it sees when it looks through the atmosphere to the ground. It could be snow and ice, the grass on a lawn, the roof of a building, or the leaves in the canopy of a forest. Thus, land surface temperature is not the same as the air temperature that is included in the daily weather report.

The maps shown here were made using data collected during the daytime by the Moderate Resolution Imaging

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d116EarthsAtmosphere.html[11/3/2014 5:18:32 PM] The Earth

Spectroradiometer (MODIS) on NASA’s Terra satellite. Temperatures range from -25 degrees Celsius (deep blue) to 45 degrees Celsius (pinkish yellow). At mid-to-high latitudes, land surface temperatures can vary throughout the year, but equatorial regions tend to remain consistently warm, and Antarctica and Greenland remain consistently cold. Altitude plays a clear role in temperatures, with mountain ranges like the North American Rockies cooler than other areas at the same latitude.

Scientists monitor land surface temperature because the warmth rising off Earth’s landscapes influences (and is influenced by) our world’s weather and climate patterns. Scientists want to monitor how increasing atmospheric greenhouse gases affect land surface temperature, and how rising land surface temperatures affect glaciers, ice sheets, permafrost, and the vegetation in Earth’s ecosystems.

Commercial farmers may also use land surface temperature maps like these to evaluate water requirements for their crops during the summer, when they are prone to heat stress. Conversely, in winter, these maps can help citrus farmers to determine where and when orange groves could have been exposed to damaging frost.

If in Chrome, Download this file to play in Windows Media Player or VLC (right-click and "Save link as") or download VLC and play in the page

FIRE: On Earth, something is always burning. Wildfires are started by lightning or accidentally by people, and people use controlled fires to manage farmland and pasture and clear natural vegetation for farmland. Fires can generate large amounts of smoke pollution, release greenhouse gases, and unintentionally degrade ecosystems. But fires can also clear away dead and dying underbrush, which can help restore an ecosystem to good health. In many ecosystems, including boreal forests and grasslands, plants have co-evolved with fire and require periodic burning to reproduce.

The fire maps show the locations of actively burning fires around the world on a monthly basis, based on observations from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite. The colors are based on a count of the number (not size) of fires observed within a 1,000-square-kilometer area. White pixels show the high end of the count —as many as 100 fires in a 1,000-square-kilometer area per day. Yellow pixels show as many as 10 fires, orange shows as many as 5 fires, and red areas as few as 1 fire per day.

Some of the global patterns that appear in the fire maps over time are the result of natural cycles of rainfall, dryness, and lightning. For example, naturally occurring fires are common in the boreal forests of Canada in the summer. In other parts of the world, the patterns are the result of human activity. For example, the intense burning in the heart of South America from August-October is a result of human-triggered fires, both intentional and accidental, in the Amazon Rainforest and the Cerrado (a grassland/savanna ecosystem) to the south. Across Africa, a band of widespread agricultural burning sweeps north to south over the continent as the dry season progresses each year. Agricultural burning occurs in late winter and early spring each year across Southeast Asia.

If in Chrome, Download this file to play in Windows Media Player or VLC (right-click and "Save link as") or download VLC and play in the page

WATER VAPOUR: Water is constantly cycling through the atmosphere. Water evaporates from the Earth’s surface and rises on warm updrafts into the atmosphere. It condenses into clouds, is blown by the wind, and then falls back to the Earth as rain or snow. This cycle is one important way that heat and energy are transferred from the surface of the Earth to the atmosphere, and transported from one place to another on our planet.

Water vapor is also the most important greenhouse gas in the atmosphere. Heat radiated from Earth’s surface is absorbed by water vapor molecules in the lower atmosphere. The water vapor molecules, in turn, radiate heat in all directions. Some of the heat returns to the Earth’'s surface. Thus, water vapor is a second source of warmth (in addition to sunlight) at the Earth’s surface.

These maps show the average amount of water vapor in a column of atmosphere in a given month. The units are given in centimeters, which is the equivalent amount of water that could be produced if all the water vapor in the column were to condense. The lowest amounts of water vapor (0 centimeters) appear in yellow, and the highest amounts (6 centimeters) appear in dark blue. Areas of missing data appear in shades of gray. The maps are based on data collected by the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor on NASA’s Aqua satellite.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d116EarthsAtmosphere.html[11/3/2014 5:18:32 PM] The Earth

The most noticeable pattern in the time series is the influence of seasonal temperature changes and incoming sunlight on water vapor. In the tropics, a band of extremely humid air wobbles north and south of the equator as the seasons change. This band of humidity is part of the Intertropical Convergence Zone, where the easterly trade winds from each hemisphere converge and produce near-daily thunderstorms and clouds. Farther from the equator, water vapor concentrations are high in the hemisphere experiencing summer and low in the one experiencing winter.

Another pattern that shows up in the time series is that water vapor amounts over land areas decrease more in winter months than adjacent ocean areas do. This is largely because air temperatures over land drop more in the winter than temperatures over the ocean. Water vapor condenses more rapidly in colder air.

If in Chrome, Download this file to play in Windows Media Player or VLC (right-click and "Save link as") or download VLC and play in the page

VEGETATION INDEX: Satellites observe global-scale patterns of vegetation that scientists use to study changes in plant growth as a result of climate and environmental changes as well as human activity. Photosynthesis plays a big role in removing carbon dioxide from the atmosphere and storing it in wood and soils, so mapping vegetation is a key part of studying the carbon cycle. Farmers and resource managers also use satellite-based vegetation maps to help them monitor the health of our forests and croplands.

On these maps, vegetation is pictured as a scale, or index, of greenness. Greenness is based on several factors: the number and type of plants, how leafy they are, and how healthy they are. In places where foliage is dense and plants are growing quickly, the index is high, represented in dark green. Regions where few plants grow have a low vegetation index, shown in tan. The index is based on measurements taken by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite. Areas where the satellite did not collect data are gray.

The most obvious pattern that the maps show is a global one: vegetation greenness is high around the equator all year long, where temperatures, rainfall and sunlight are abundant. Between the equator and the poles, the vegetation greenness rises and falls as the seasons change.

If in Chrome, Download this file to play in Windows Media Player or VLC (right-click and "Save link as") or download VLC and play in the page

NASA Earth Observatory

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d116EarthsAtmosphere.html[11/3/2014 5:18:32 PM] Introduction - Water Supplies

Present Situation - Water Supplies and Sanitation

What is the current situation with regard to provision of safe water and sanitation?

According to the United Nations, the world has already (in 2010) met the Millenium Development Goals (MDGs) for increasing by 50% the world population with access to improved drinking water by 2015:

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d120PresentSituation.html[11/3/2014 5:18:32 PM] Introduction - Water Supplies

"TARGET: Halve, by 2015, the proportion of the population without sustainable access to safe drinking water and basic sanitation. file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d120PresentSituation.html[11/3/2014 5:18:32 PM] Introduction - Water Supplies

In four of nine developing regions, 90 per cent or more of the population now uses an improved drinking water source. In contrast, coverage remains very low in Oceania and sub-Saharan Africa, neither of which is on track to meet the MDG drinking water target by 2015. Over 40 per cent of all people without improved drinking water live in sub-Saharan Africa. Since it is not yet possible to measure water quality globally, dimensions of safety, reliability and sustainability are not reflected in the proxy indicator used to track progress towards the MDG target. As a result, it is likely that the number of people using improved water sources is an overestimate of the actual number of people using safe water supplies.Continued efforts are required to promote global monitoring of drinking water safety, reliability andsustainability and to move beyond the MDG water target to universal coverage."

Rural areas fared worse than urban areas

"Coverage with improved drinking water sources for rural populations is still lagging. In 2010, 96 per cent the urban population used an improved drinking water source, compared with 81 per cent of the rural population. In absolute terms, because of population growth, the number of people without an improved source in urban areas actually increased. In rural areas, on the other hand, the number of people without an improved source of water decreased, from 1.1 billion in 1990 to 653 million in 2010. However, the gap between urban and rural areas still remains wide, with the number of people in rural areas without an improved water source five times greater than in urban areas."

The global picture for access to water is shown on the map below. The different kinds of water scarcity reflect the that water can be considered scarce for a variety of reasons, not simple physical lack of water, but also that the cost of water extraction can make it unavailable (economic water scarcity).

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d120PresentSituation.html[11/3/2014 5:18:32 PM] Introduction - Water Supplies

Progress towards the MDGs on the sanitation target has been much slower.

The greatest progress was achieved in Eastern and Southern Asia, where sanitation coverage in 2010 was, respectively, 2.4 and 1.7 times higher than in 1990. In contrast, progress was slowest in Western Asia and sub- Saharan Africa, and no improvement was achieved in Oceania over the 20-year period. At the current pace, and barring additional interventions, by 2015 the world will have reached only 67 per cencoverage, well short of the 75 per cent needed to achieve the MDG target."

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d120PresentSituation.html[11/3/2014 5:18:32 PM] Introduction - Water Supplies

The complete report (in Adobe Acrobat pdf format) on progress towards all of the MDGs is available locally here:

Click the image to access a local copy in Adobe PDF format

Click here for a local Summary of the Report in HTML format file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d120PresentSituation.html[11/3/2014 5:18:32 PM] Introduction - Water Supplies

Or go to the UN website at http://www.un.org/millenniumgoals/pdf/MDG_Report_202012.pdf to see the full report (Internet Access Required)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d120PresentSituation.html[11/3/2014 5:18:32 PM] The Hydrologic Cycle

The Hydrologic Cycle

The Earth's Water Cycle movie (below) from NASA shows the cycling of water around the Earth.

The Movie below will play in most recent versions of Chrome, Firefox, Opera, Microsoft Explorer, and Safari

Video is not visible, most likely your browser does not support HTML5 video

Water is the fundamental ingredient for life on Earth. Looking at our Earth from space, with its vast and deep ocean,s thougere is an abundance of water for our use. However, only a small portion of Earth's water is accessible for our needs. How much fresh water exists and where it is stored affects us all. This animation uses Earth science data from a variety of sensors on NASA Earth observing satellites as well as cartoons to describe Earth's water cycle and the continuous movement of water on, above and below the surface of the Earth. Sensors on a suite of NASA satellites observe and measure water on land, in the ocean and in the atmosphere. These measurements are important to understanding the availability and distribution of Earth's water -- vital to life and vulnerable to the impacts of climate change on a growing world population. This video is public domain.

NASA Earth Observing System Data and Information Systems (EOSDIS) EOSDIS is a distributed system of twelve data centers and science investigator processing systems. EOSDIS processes, archives, and distributes data from Earth observing satellites, field campaigns, airborne sensors, and related Earth science programs. These data enable the study of Earth from space to advance scientific understanding.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d150WaterCycleVideos.html[11/3/2014 5:18:33 PM] The Hydrologic Cycle

Why is water so important?

1. Freshwater resources are unevenly distributed, with much of the water located far from human populations. Many of the world’s largest river basins run through thinly populated regions. There are an estimated 263 international rivers, covering 45.3% of the land-surface of the earth (excluding Antarctica).

2. Groundwater represents about 90% of the world’s readily available freshwater resources, and some 1.5 billion people depend upon groundwater for their drinking water.

3. Agricultural water use accounts for about 70% of total global consumption - mainly through crop irrigation - while industrial use accounts for about 20%, and the remaining 10% is used for domestic purposes

4. It is estimated that two out of every three people will live in water-stressed areas by the year 2025. In Africa alone, it is estimated that 25 countries will be experiencing water stress (below 1,700 m3 per capita per year) by 2025. Today, 450 million people in 29 countries suffer from water shortages.

Annual global freshwater withdrawal has grown from 3,790 km3 (of which consumption accounted for 2,070 km3 or 61%) in 1995, to 4,430 km3 (of which consumption accounted for 2,304 km3 or 52%) in 2000 (Shiklomanov, 1999).

In 2000, about 57% of the world’s freshwater withdrawal, and 70% of its consumption, took place in Asia, where the world’s major irrigated lands are located (UNESCO, 1999).

In the future, annual global water withdrawal is expected to grow by about 10-12% every 10 years, reaching approximately 5,240 km3 (or an increase of 1.38 times since 1995) by 2025. Water consumption is expected to grow at a slower rate of 1.33 times (UNESCO, 1999).

In the coming decades, the most intensive rate of water withdrawal is expected to occur in Africa and South America (increasing by 1.5-1.6 times), while the least will take place in Europe and North America (1.2 times) (Harrison and Pearce, 2001; Shiklomanov, 1999; UNESCO, 1999).

Annual global freshwater withdrawal has grown from 3,790 km3 (of which consumption accounted for 2,070 km3 or 61%) in 1995, to 4,430 km3 (of which consumption accounted for 2,304 km3 or 52%) in 2000

In 2000, about 57% of the world’s freshwater withdrawal, and 70% of its consumption, took place in Asia, where the world’s major irrigated lands are located

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d160Importanceofwater.html[11/3/2014 5:18:33 PM] The Hydrologic Cycle

5. Clean water supplies and sanitation remain major problems in many parts of the world, with 20% of the global population lacking access to safe drinking water. Around 1.1 billion people globally do not have access to improved water supply sources, while 2.4 billion people do not have access to any type of improved sanitation facility. About 2 million people die every year due to waterborne diseases from faecal pollution of surface waters; most of them are children less than five years of age. A wide variety of human activities also affect the coastal and marine environment. Population pressures, increasing demand for space and resources, and poor economic performance can all undermine the sustainable use of our oceans and coastal areas.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d160Importanceofwater.html[11/3/2014 5:18:33 PM] The Hydrologic Cycle

6. Serious problems affecting the quality and use of these ecosystems include the alteration and destruction of habitats and ecosystems. For example:

Estimates show that almost 50% of the world’s coasts are threatened by development-related activities. Severe eutrophication has been discovered in several enclosed or semi-enclosed seas. It is estimated that about 80% of marine pollution originates from land-based sources and activities.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d160Importanceofwater.html[11/3/2014 5:18:33 PM] The Hydrologic Cycle

In marine fisheries, most areas are producing significantly lower yields than in the past. Substantial increases are never again likely to be recorded for global fish catches. In contrast, inland and marine aquaculture production is increasing and now contributes 30% of the total global fish yield.

7. The impact of climate change is projected to include a significant rise in the level of the world’s oceans. This will cause some low lying coastal areas to become completely submerged, and increase human vulnerability in other areas. Small Island Developing States (SIDS), which are highly dependent upon marine resources, are especially vulnerable, due to both the effects of sea level rise and to changes in marine ecosystems.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d160Importanceofwater.html[11/3/2014 5:18:33 PM] The Hydrologic Cycle

This can lead to many effects. One might be an increase in disease spread

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d160Importanceofwater.html[11/3/2014 5:18:33 PM] The Hydrologic Cycle

Climate Change, Water and Health

Heavy rainfall or flooding can increase water-borne parasites such as Cryptosporidium and Giardia that are sometimes found in drinking water. These parasites can cause gastrointestinal distress and in severe cases, death. The distribution of diseases and disease vectors (such as the malarial mosquito) may change as the climate changes Heavy rainfall events cause stormwater runoff that may contaminate water bodies used for recreation (such as lakes and beaches) with other bacteria. The most common illness contracted from contamination at beaches is gastroenteritis, an inflammation of the stomach and the intestines that can cause symptoms such as vomiting, headaches, and fever. Other minor illnesses include ear, eye, nose, and throat infections Flooding and heavy rainfall can cause overflows from sewage treatment plants into fresh water sources. Changes in temperature and precipitation, as well as droughts and floods, will likely affect agricultural yields and production. In some regions of the world, these impacts may compromise food security and threaten human health through malnutrition, the spread of infectious diseases, and food poisoning. The worst of these effects are projected to occur in developing countries, among vulnerable populations.

In the USA, for example, it has been calculated that water shortages will occur in 33% of the counties in the lower 48 states and 400 of these will face extyreme water shortage.

Worldwide, water availability will change drastically (both higher and lower) over the next few decades

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d170climatechange.html[11/3/2014 5:18:34 PM] The Hydrologic Cycle

The Science of Global Climate Change

For an excellent summary of the science of global warming, see the Summary of the Physical Science basis for GCC from the IPCC (Intergovernmental Panel on Climate Change) on the CD and the website at http://ipcc.ch/ (Internet Access Required)

One of the many Figures from the IPCC report quite clearly shows some of the impacts of Global Climate Change - there are many others!

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d170climatechange.html[11/3/2014 5:18:34 PM] The Hydrologic Cycle

Also see the large poster produced on "Climate Change 2013: The Physical Science Basis" on the CD.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d170climatechange.html[11/3/2014 5:18:34 PM] The Hydrologic Cycle

One part of the poster shows the likely scenarios of continued global warming:

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d170climatechange.html[11/3/2014 5:18:34 PM] Water and civilizations

Water and civilizations

The Fertile Crescent. The Fertile Crescent is the region in the Middle East which encompasses modern- day southern Iraq, Syria, Lebanon, Jordan, Israel and northern Egypt

The Indus Valley Civilization The Indus Valley Civilization was a Bronze Age Civilization in the northwestern region of the Indian subcontinent, consisting of what is now mainly present-day Pakistan and northwest India

Egypt For almost 30 centuries—from its unification around 3100 B.C. to its conquest by Alexander the Great in 332 B.C.—ancient Egypt was the preeminent civilization in the Mediterranean world

Greece The history of Greece can be traced back to Stone Age hunters. Later came early farmers and the civilizations of the Minoan and Mycenaean kings. This was followed by a period of wars and invasions, known as the Dark Ages. Classical period of ancient Greek history, is fixed between about 500 B. C., when the Greeks began to come into conflict with the kingdom of Persia to the east, and the death of the Macedonian king and conqueror Alexander the Great in 323 B.C. In this period Athens reached its greatest political and cultural heights. The Hellenistic Period (336-146 BC) was the period between the conquest of the Persian Empire by Alexander the Great and the establishment of Roman supremacy, in which Greek culture and learning were pre-eminent in the Mediterranean and Asia Minor.

Rome In its approximately twelve centuries of existence, Roman civilization shifted from a monarchy to an aristocratic republic to an increasingly autocratic empire. Through conquest and assimilation, it came to dominate Southern Europe, Western Europe, Asia Minor, North Africa, parts of Northern Europe, and parts of Eastern Europe. Rome was preponderant throughout the Mediterranean region and was one of the most powerful entities of the ancient world. It is often grouped into Classical Antiquity together with ancient Greece, and their similar cultures and societies are known as the Greco-Roman world

A comprehensive treatment of ancient water technologies can be viewed in:

"Ancient Water Technologies" Edited by Larry Mays (on CD)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d200WaterandCivilizationTITLE.html[11/3/2014 5:18:35 PM] Civilizations and Water

The Fertile Crescent

Mesopotamia is in the east side of the region named “fertile crescent”, where agriculture flourished and the earliest civilizations were born more than eight thousand years ago. In the alluvial plain of Lower Mesopotamia agriculture based on irrigation developed, in contrast to the Upper Mesopotamia, where dry-farming was possible. A complex system of canals and waterworks developed, with the dual function to ensure irrigation and to be used as waterways. Control of water was decisive as a way to guarantee economic prosperity, but also was a source of interstate conflicts and a political tool. Water technology was not limited to irrigation, Mesopotamians also pioneered in sanitary engineering, with many cities presenting networks of wastewater and storm water drainage systems. Overexploitation of land and water resources for agriculture affected the environment, resulting in silting and soil salinization, matter that has been recorded since the earliest cuneiform writings (Ancient Water Technologies, Larry W. Mays Editor 2010)

Irrigation:

Lift Irrigation

The first devices were human-powered. The shaduf had a bag and rope attached to the one end of a wooded arm or beam with a counter balance at the other end of the arm. The beam rotates around an axis so that the person operating the shaduf pulls down the bag into the water, then lifts the bag with water, and then drops the water from the bag. The shaduf was known in Mesopotamia as early as the time of Sargon of Akkad (ca. 2300 B.C.).

Qanat

The qanat is a collection and conveyance system for groundwater that was developed in Persia. It consists of an underground tunnel which uses gravity to convey water from the water table (or springs) at higher elevations to the surface of lower lands. Qanats also have a series of vertical shafts that were used for excavation of the tunnel and provided air circulation and lighting. The oldest qanats have been found in the northern part of Iran and date back to around 3,000 years ago when the Arians (Aryans) settled in present day Iran file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d202WaterandCivilization.html[11/3/2014 5:18:35 PM] Civilizations and Water

Urban Water Supply

Urban Water Sources

The sources of water for some early cities or, sometimes, just the ruler's palaces were:

Short canal connected to permanent river Canals and reservoirs storing flood water of nonpermanent river, rainfall Rainwater harvesting (gutters and cisterns) Shallow Wells Aqueducts from source at altitude Underground cisterns w/ steps Springs

Sanitation

There is evidence that, as early as 6500 B.C., there was a well developed urban settlement at El Kowm 2, Central Syria, about 80 km south from the Euphrates. The city had well planned houses, many of them with drainage systems for domestic wastewater. Many cities of Mesopotamia had networks of wastewater and storm water drainage systems.

Water Treatment and Settling Basin

Perhaps most surprising to modern day hydraulic engineers is the very early engineering works in Sumaria. Kang (1973) proposed a system of Sumerian canal and irrigation systems as a multi- purpose settling-reservoir, serving ‘to facilitate intersections, to slow water flow from higher to a lower plane, to prevent scouring and erosion, and to act as a kind of a simple reservoir’. However, according to Kang, its primary importance was to serve as a sedimentation basin, as storage and water regulator, and as a reservoir for dry seasons. It is remarkably similar to todays sedimentation basins for run-off water and the sedimentation systems used to remove suspended solids from water.

The settling-reservoir (nag-ku5) and complementary water-works,

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d202WaterandCivilization.html[11/3/2014 5:18:35 PM] Civilizations and Water

Egypt

The ancient Egyptians depended upon the Nile not only for their livelihoods, but they also considered the Nile to be a deific force of the universe, to be respected and honored if they wanted it to treat them favorably. Its annual rise and fall were likened to the rise and fall of the sun, each cycle equally important to their lives, though both remaining a mystery. Since the Nile sources were unknown up until the 19th century, the Ancient Egyptians believed it to be a part of the great celestial ocean, or the sea that surrounds the whole world.

The Nile seen from space, nearly 6,650 km in total length, drains an estimated 3,350,000 km2, which is about one-tenth of the African continent with catchments in nine different countries.

Sad-el-Kaffara Early Egyptian periods (6000 to 3000 BCE) depended on the flooding of the Nile to both irrigate and fertilize the soil. Around 3000BCE, artificial canals began to appear and led to larger areas being irrigated. Artificial irrigation increased the area of annual cropland in relation to the flood stage; retained water in the basin after smaller floods; and allowed second and even third crops in some basins. This form of water management, called basin irrigation, consisted of a network of earthen banks, some parallel to the river and some perpendicular to the river that formed basins of various sizes.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d203WaterandCivilization.html[11/3/2014 5:18:35 PM] Civilizations and Water

Floodwaters were diverted into the basins where the water was allowed to saturate the soil with the remaining water drained off to a down-gradient basin or to a canal. After the draining process was completed in a basin, crops were planted. King Menes, the founder of the first dynasty in 3100 B.C. traditionally has been known as the first to develop a major basin irrigation project. About 1500 BCE, lift irrigation started and was well advanced by Roman times. Oldest records of Nile flood levels were carved on a large stone monument from approximately 2480 BCE.

The Sadd-el-Kafara dam (Dam of the Pagans) was constructed about 2600–2700 B.C. The dam was constructed around 2650 and was the first attempt at storing water on a large scale. Possibly older dams include the Jawa reservoir in Jordan and diversion dams on the Kasakh River in the southern part of the former Soviet Union. However these structures were much smaller than the Sadd- el-Kafara dam so Sadd-el-Kafar is probably the world’s oldest large- scale dam.

Urban Water Supply

Urban Water Sources

The sources of water in Ancient Egypt were

The Nile Canals and reservoirs storing flood water Shallow Wells Springs

Sanitation

Women would walk to the Nile, in groups, to fetch the water needed file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d203WaterandCivilization.html[11/3/2014 5:18:35 PM] Civilizations and Water

for drinking, washing and cooking. Female servants (baket) made frequent trips, transporting heavy jars balanced on their heads. The streets of ancient Egypt lacked a proper drainage system. Canals were used to draw away waste. The disposal of refuse was always a major concern. Household garbage was heaped into a dump outside the town and burned, or leveled, and houses would later be built on the site. Sewage was disposed of in the river as well as in the alleys.

http://emhotep.net/2013/02/25/emhotep-digest/em-hotep-digest-vol- 02-no-07-daily-life-in-ancient- egypt/ Internet Access Required)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d203WaterandCivilization.html[11/3/2014 5:18:35 PM] Civilizations and Water

Greece

The ancient Greeks invented many features of modern civilization. A brief list shows how much we owe to their ingenuity. Their achievements in water technology were impressive; in 250 BCE they invented the water mill and in circa 250 BCE they pioneered the water wheel. They had air and water pumps, indoor plumbing, central heating, showers and built canal locks an ancient version of the Suez Canal.

For example:

A shower room for female athletes with plumbed-in water is depicted on an Athenian vase.

A whole complex of shower-baths was also found in a 2nd-century BC gymnasium at Pergamum. and excavations at Olympus as well as Athens have revealed extensive plumbing systems for baths and fountains as well as for personal use.

They used groundwater, constructed aqueducts for water supply, used storm water and wastewater sewerage systems, flood protection and drainage, and constructed and used fountains, baths and other sanitary and purgatory facilities.

As well as many water-related inventions, they also invented the first Streets, use of Cartography, Calipers, Truss roof, Crane, Escapement, Tumbler lock, Gears, Spiral staircase, Urban Planning, Crossbow, Winch, Wheelbarrow, Central heating, Lead sheathing, Astrolabe, Lighthouse, Alarm clock, Odometer, Chain drive, Cannon, Double-action principle, Levers, Three-masted ship (mizzen), Gimbal, Sakia gear,Surveying tools, Fore-and-aft rig (spritsail), Analog computers, Fire hose, Vending machine, Wind vane, Clock tower and Automatic doors ---- an impressive list. There are many more.....

Some examples of Greek inventions:

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d205WaterandCivilization.html[11/3/2014 5:18:35 PM] Civilizations and Water

Washstand

Philo of Byzantium (3rd century BC) in his technical treatise Pneumatics (chapter 31) as part of a washstand automaton for guests washing their hands. Philon's comment that "its construction is similar to that of clocks" indicates that such escapements mechanism were already integrated in ancient water clocks

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d205WaterandCivilization.html[11/3/2014 5:18:35 PM] Civilizations and Water

Crossbow

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d205WaterandCivilization.html[11/3/2014 5:18:35 PM] Civilizations and Water

Lighthouse: Pharos of Alexandria

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d205WaterandCivilization.html[11/3/2014 5:18:35 PM] Civilizations and Water

Clock Tower: Tower of the Wind

The watermill

The earliest machine harnessing natural forces (apart from the sail) and as such holding a special place in the history of technology, was invented by Greek engineers somewhere between the 3rd and 1st centuries BC. The image is a Roman gristmill as described by Vitruvius.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d205WaterandCivilization.html[11/3/2014 5:18:35 PM] Civilizations and Water

Rome

Dams: Roman dam construction was characterized by "the Romans' ability to plan and organize engineering construction on a grand scale". Roman planners introduced the then novel concept of large reservoir dams which could secure a permanent water supply for urban settlements also over the dry season. Their pioneering use of water-proof hydraulic mortar and particularly Roman concrete allowed for much larger dam structures than previously built, such as the Lake Homs Dam, possibly the largest water barrier to that date, and the Harbaqa Dam, both in Roman Syria. The highest Roman dam was the Subiaco Dam near Rome; its record height of 50 m (160 ft.) remained unsurpassed until its accidental destruction in 1305. Roman engineers made routine use of ancient standard designs like embankment dams and masonry gravity dams. Apart from that, they displayed a high degree of inventiveness, introducing most of the other basic dam designs which had been unknown until then. These include arch-gravity dams, arch dams, buttress dams and multiple arch buttress dams, all of which were known and employed by the 2nd century AD (see List of Roman dams). Roman workforces also were the first to build dam bridges, such as the Bridge of Valerian in Iran Roman dam construction began in earnest in the early imperial period. For the most part, it concentrated on the semi-arid fringe of the empire, namely the provinces of North Africa, the Near East, and Hispania. The relative abundance of Spanish dams below is due partly to more intensive field work there; for Italy only the Subiaco Dams, created by emperor Nero (54–68 AD) for recreational purposes, are attested. These dams are noteworthy, though, for their extraordinary height, which remained unsurpassed anywhere in the world until the Late Middle Ages The most frequent dam types were earth- or rock-filled embankment dams and masonry gravity dams. These served a wide array of purposes, such as irrigation, flood control, river diversion, soil-retention, or a combination of these functions. In this, Roman engineering did not differ fundamentally from the practices of older hydraulic societies. "The Romans' ability to plan and organize engineering construction on a grand scale" gave their dam construction special distinction. Their engineering prowess, therefore, facilitated the construction of large and novel reservoir dams, which secured a permanent water supply for urban settlements even during the dry season, a common concept today, but little-understood and - employed in ancient times. The impermeability of Roman dams was increased by the introduction of water-proof hydraulic mortar and especially opus caementicium in the Concrete Revolution. These materials also allowed for bigger structures to be built, like the Lake Homs Dam, possibly the largest water barrier to date, and the sturdy Harbaqa Dam, both of which consist of a concrete core. On the whole, Roman dam engineering displayed a high degree of completeness and innovativeness. While hitherto dams relied solely on their heavy weight to resist the thrust of water, Roman builders were the first to realize the stabilizing effect of arches and buttresses, which they integrated into their dam designs. Previously unknown dam types introduced by the Romans include:

Aqueducts:

The Romans constructed numerous aqueducts to bring water from distant sources into their cities and towns, supplying public baths, latrines, fountains and private households. Waste water was removed by complex sewage systems and released into nearby bodies of water, keeping the towns clean and free from effluent. Some aqueducts also provided water for mining operations and the milling of grain. Aqueducts moved water through gravity alone, being constructed along a slight downward gradient within conduits of stone, brick or concrete. Most were buried beneath the ground, and followed its contours; obstructing peaks were circumvented or, less often, tunneled through. Where valleys or lowlands intervened, the conduit was carried on bridgework, or its contents fed into high- pressure lead, ceramic or stone pipes and siphoned across. Most aqueduct systems included sedimentation tanks, sluices and distribution tanks to regulate the supply at need. Rome's first aqueduct supplied a water-fountain sited at the city's cattle-market. By the third century AD, the city had eleven aqueducts, sustaining a population of over a million in a water-extravagant economy; most of the water supplied the city's many

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d260WaterandCivilization.html[11/3/2014 5:18:36 PM] Civilizations and Water

public baths. Cities and municipalities throughout the Roman Empire emulated this model, and funded aqueducts as objects of public interest and civic pride, "an expensive yet necessary luxury to which all could, and did, aspire." Most Roman aqueducts proved reliable, and durable; some were maintained into the early modern era, and a few are still partly in use. Methods of aqueduct surveying and construction are noted by Vitruvius in his work De Architectura (1st century BC). The general Frontinus gives more detail in his official report on the problems, uses and abuses of Imperial Rome's public water supply. Notable examples of aqueduct architecture include the supporting piers of the Aqueduct of Segovia, and the aqueduct-fed cisterns of Constantinople.

The multiple arches of the Pont du Gard in Roman Gaul(modern-day southern France). Its lower tiers carry a road across the river, and the upper tiers support an aqueduct conduit that carried water to Nimes in Roman times.

Water Wheels:

Another fascinating technology used by the Romans was the water wheel (Noria) which is represented in 4th century AD mosaics from Syria. The noria is powered by the flow of a river and lifts water in buckets to fields or aqueducts. There remain a number of ancient Arabic water wheels along the Orontes River in and near Hama. These water works date back to medieval times and as late as 1985 there were about 80 in use along the file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d260WaterandCivilization.html[11/3/2014 5:18:36 PM] Civilizations and Water

river irrigating over 5000 ha. Today only a handful remain and those in Hama itself are tourist attractions for the city – ancient and elegant reminders of the long history of water management and transference in Syria.

Water wheel (Noria) and aqueduct at Hama

Cisterns:

One type of Roman water work that is extremely abundant, and often still functional, is the Roman Cistern (Abar Romani). These are small excavated caverns, often lined with Roman hydraulic cement, that capture surface flow from the winter rains for use in the dry summer. They typically have a large stone cover to protect the water. There are at least 1115 of these cisterns in Syria.

Roman Sanitation Technologies:

The Romans were one of the first known civilizations to invent indoor plumbing. The Roman public baths, or thermae served hygienic, social and cultural functions. The baths contained three main facilities for bathing. After undressing in the apodyterium or changing room, Romans would proceed to the tepidarium or warm room. In the moderate dry heat of the tepidarium, some performed warm-up exercises and stretched while others oiled themselves or had slaves oil them. The tepidarium’s main purpose was to promote sweating to prepare for the next room, the caldarium or hot room. The caldarium, unlike the tepidarium, was extremely humid and hot. Temperatures in the caldarium could reach 40 degrees Celsius (104 degrees Fahrenheit). Many contained steam baths and a cold-water fountain known as the labrum. The last room was the frigidarium or cold room, which offered a cold bath for cooling off after the caldarium. The Romans also had flush toilets.

These levels of sophisticated water supply systems, sanitation and management of water were not approached again until the 19th and 20th centuries, except for isolated remnants of technology in some parts of the world

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d260WaterandCivilization.html[11/3/2014 5:18:36 PM] Civilizations from 1000 AD to the present

Civilizations from 1000 AD to the present

Previously, we examined the contribution of ancient civilizations in different regions to the development of water technologies, processes and looked at the advances in health and hygiene flowing from those advances.

A timeline of civilizations in the various regions of the world shows the changes that have occurred in the past 1000+ years. Most continents and regions have examples of relatively advanced civilizations in that period and many have had advanced civilizations for very long periods of time.

In many of those cases, the different cultures in the last 1000+ years developed different methods for handling water supply, treatment and distribution, but, as we will show in the next sections of the course, in many other cases they invented or used remarkably similar approaches to those issues. In fact, many of the solutions were developed in the ancient world and were not significantly improved until the industrial era.

Some innovations in engineering and science happened during this period, but it was not until the advent of water purification technologies in the late 19th century and the discovery of the disease causing microorganisms in the same time period that massive improvements in It could be argued that many of the sanitation the health of the public in some of those regions occurred. and water technology and distribution systems developed in the ancient Greek, Roman, As is evident in the video below showing the changes in borders and Mayan, Middle Eastern and other old countries in Europe between 1000 CE and the present day, one civilizations were essentially "lost" as those important reason for the lack of progress was constant turmoil, civilizations declined and had to be reinvented invasions, wars and fragmentation of countries. The same was true for or rediscovered much later in history. much of the rest of the world.

If video is not visible, most likely your browser does not support HTML5 video

Changes in Europe between 1000 CE and the present day.

Also available from: http://www.liveleak.com/view?i=f54_1337075813&use_old_player=1

(Internet connection required for link - Right-click and Open as New Window)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d280AD1000toPresent.html[11/3/2014 5:18:36 PM] Main Reasons for European/Eurasi

European Dominance Main Reasons for European/Eurasian Dominance

Trade and Capital: · The Empires in China and India kept themselves more isolated. The Europeans (starting in Italy) carried out more trade. · They used superior weapons to enforce trade and to colonize. Agriculture and crops: · European trade and dominance led to a “globalization” of agricultural crops (maize, cassava, potatoes and wheat) Technology and Institutions: · Europe advanced until around 1500 by importing the technologies developed in the Middle East, India and China . The change around 1500 was due to steadily increasing populations, urban centre development (with universities, the church, financial institutions, and trade). · Culminated in the Industrial Revolution (starting around 1820)

Results: In 1820, the economic level of Europe, North America and Japan were only about twice that of the rest of the world. The level is now approximately 7 times that of the “rest of the world” Asia has started to close the gap. The total disparity between high and low income countries continues to grow

Some other observations: · Total size of the world economy has increased 300 fold in the last 1000 years · Total population has increased about 20 fold (from 0.3 to 6 billion) · Therefore the total economic activity per capita has increased 15 fold.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d281EuropeanDominance.html[11/3/2014 5:18:36 PM] Population Increase

Population Increase Theoretical rate of Population Increase

Assumptions; 4 children survive per couple per generation (i.e. population doubles each generation) and all survivors produce 4 surviving children.

This very large, hypothetical, population increase has only been approached in the modern era. The growth rate during the early Stone Age was, in fact, 0.02% per year (one person per 1000 people per generation!). The reasons for this low rate were numerous and included: Very harsh living conditions; leading to: – High mortality rates (children and adults) – Short life expectancies – Infanticide – Expulsion of young adults

The World population 10,000 years ago was approximately 10 million (same as Sweden today) after about 90,000 years (4000 generations) of existence of Homo sapiens

The graph of actual population increase shows the dramatic increase in the last 300 years. Some of this increase can undoubtedly be ascribed to better water management in agriculture, drinking water and sanitation

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d282population.html[11/3/2014 5:18:36 PM] Population Increase

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d282population.html[11/3/2014 5:18:36 PM] Civilizations from 1000 AD to the present

Summary of All History (or, more accurately, the last 4000 years)

In 1931, John B. Sparks created a "histomap" that distilled the history of civilization into a colorful timeline. See 4,000 years of empires rising and falling, and even though it stops after World War I, you can imagine how it would look if it were continued. The original can be seen at -http://www.slate.com/blogs/the_vault/2013/08/12/the_1931_histomap_the_entire_history_of_the_world_distilled_into_a_single.html (Internet Connection Required)

The chart emphasizes domination, using color to show how the power of various “peoples” (a quasi-racial understanding of the nature of human groups, quite popular at the time) evolved throughout history.

This is a huge image and may be too big for your screen, depending on the browser you use, but you can usually navigate around by using the scroll bars.

If you simply look at the patterns on the chart, it is easy too see how most empires and civilizations had short lifetimes and have now gone. Notable exceptions are the Indian and Chinese civilizations - still important today (even more so now than when this chart was finished). Others lasted a long time but are no longer existing as important civilizations (even though the countries may still be with us). Examples are the Mongolian, Ottoman, Greek and Roman empires.

Note: This chart is for reference ONLY. It is here to give you an overview of history for the last 4000 years. Probably nobody in the world knows the details of everything behind this chart. If they do, they are a candidate for one of the many TV quiz shows out there. For an even more detailed treatment see http://en.wikipedia.org/wiki/Ancient_history (Internet Connection Required)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d285HistoryWorldoneChart.html[11/3/2014 5:18:37 PM] Civilizations from 1000 AD to the present

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d285HistoryWorldoneChart.html[11/3/2014 5:18:37 PM] Global Health Risks

Global Health Risks

The global burden of diseases and injuries - World Health Organization 2009 update (on CD)

World Health Statistics - 2013 - World Health Organization (on CD)

More than one third of the world’s deaths can be attributed to a small number of risk factors. The 24 risk factors described in this report are responsible for 44% of global deaths and 34% of DALYs; the 10 leading risk factors account for 33% of deaths. Understanding the role of these risk factors is key to developing a clear and effective strategy for improving global health. The five leading global risks for mortality in the world are high blood pressure, tobacco use, high blood glucose, physical inactivity, and overweight and obesity. They are responsible for raising the risk of chronic diseases, such as heart disease and cancers. They affect countries across all income groups: high, middle and low.

This report measures the burden of disease, or lost years of healthy life, using the DALY: a measure that gives more weight to non-fatal loss of health and deaths at younger ages. The leading global risks for burden of disease in the world are underweight and unsafe sex, followed by alcohol use and unsafe water, sanitation and hygiene.

Three of the four leading risks for DALYs – underweight, unsafe sex, and unsafe water, sanitation and hygiene – increase the number and severity of new cases of infectious diseases, and particularly affect populations in low-income countries, especially in the regions of South-East Asia and sub- Saharan Africa.

Note the relative importance of water-related diseases and unsafe water, sanitation and hygiene in the various tables and figures.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d300GlobalHealthRisksTitle.html[11/3/2014 5:18:43 PM] Global Health Risks

Ranking of selected risk factors: 10 leading causes of death by income group, 2004

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d300GlobalHealthRisksTitle.html[11/3/2014 5:18:43 PM] Global Health Risks

Ranking of selected risk factors: 10 leading causes of DALY's by income group, 2004

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d300GlobalHealthRisksTitle.html[11/3/2014 5:18:43 PM] Global Health Risks

Major Causes of death in children under 5 years old with disease specific contribution of undernutrition

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d300GlobalHealthRisksTitle.html[11/3/2014 5:18:43 PM] Global Health Risks

Deaths and DALYS from Selected Water-Related Diseases, 2000 and 2004

2000 2004 Deaths DALYS Death DALYS Diarrheal diseases 2,019,585 63,345,722 2,163,283 72,776,516 Childhood cluster diseases Poliomyelitis 1,136 188,543 1,195 34,399 Diphtheria 5,527 187,838 5,091 173,575 Tropical-cluster diseases Trypanosomiasis 49,129 1,570,242 52,347 1,672,728 Schistosomiasis 15,335 1,711,522 41,087 1,707,144 Trachoma 72 3,892,326 108 1,334,414 Intestinal nematode infections Ascariasis 4,929 1,204,384 2,455 1,850,781 Trichuriasis 2,393 1,661,689 1,828 1,012,138 Hookworm disease 3,477 1,785,539 242 1,091,589 Other Intestinal Infections 1,692 53,222 1,957 58,158 TOTAL 2,103,274 75,601,028 2,269,593 81,711,443

Source (2004 data): http://www.who.int/healthinfo/global_burden_disease/estimates_regional/en/index.html (Internet Connection Required)

There has been an improvement in many areas based on the estimates below of Global Morbidity and Mortality of Water- Related Diseases from the early 1990s;

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d300GlobalHealthRisksTitle.html[11/3/2014 5:18:43 PM] Global Health Risks

Disease Morbidity (episodes/year or people infected) Mortality (deaths/year)

Diarrheal Diseases 1,000,000,000 3,300,000

Intestinal Helminths 1,500,000,000 (people infected) 100,000

Schistosomiasis 200,000,000 (people infected) 200,000

Dracunculiasis 150,000 (in 1996) -

Trachoma 150,000,000 (active cases) -

Malaria 400,000,000 1,500,000

Dengue Fever 1,750,000 20,000

Poliomyelitis 114,000 -

Trypanosomiasis 275,000 130,000

Bancroftian Filariasis 72,800,000 (people infected) -

Onchocerciasis 17,700,000 (people infected; 270,000 blind) 40,000 (mortality caused by blindness)

Data from World Health Organization, 1995, "Community Water Supply and Sanitation: Needs, Challenges and Health Objectives." 48th World Health Assembly, A48/INF.DOC./2,28 April, Geneva, Switzerland.

The WHO World Health Statistics for 2013 (download a local copy as a pdf file)

has numerous statistics that include some on water and sanitation.

Just as examples, here are some extracts from the Index to the report:

1. Life expectancy and mortality 49 Life expectancy at birth (years) Life expectancy at age 60 (years) Stillbirth rate (per 1000 total births) Neonatal mortality rate (per 1000 live births) Infant mortality rate (probability of dying by age 1 per 1000 live births)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d300GlobalHealthRisksTitle.html[11/3/2014 5:18:43 PM] Global Health Risks

Under-five mortality rate (probability of dying by age 5 per 1000 live births) Adult mortality rate (probability of dying between 15 and 60 years of age per 1000 population)

2. Cause-specific mortality and morbidity 61 Mortality Age-standardized mortality rates by cause (per 100 000 population) Number of deaths among children aged < 5 years (000s) Distribution of causes of death among children aged < 5 years (%) Age-standardized adult mortality rate by cause (ages 30–70 per 100 000 population) Maternal mortality ratio (per 100 000 live births) Cause-specific mortality rate (per 100 000 population) Morbidity Incidence rate (per 100 000 population) Prevalence (per 100 000 population)

3. Selected infectious diseases Cholera Diphtheria H5N1 influenza Japanese encephalitis Leprosy Malaria Measles Meningitis Mumps Pertussis Plague Poliomyelitis Congenital rubella syndrome Rubella Neonatal tetanus Total tetanus Tuberculosis Yellow fever

5. Risk factors Population using improved drinking-water sources (%) Population using improved sanitation (%) Population using solid fuels (%) Preterm birth rate (per 100 live births) Infants exclusively breastfed for the first 6 months of life (%) Children aged < 5 years who are wasted (%) Children aged < 5 years who are stunted (%) Children aged < 5 years who are underweight (%) Children aged < 5 years who are overweight (%) Prevalence of raised fasting blood glucose among adults aged ≥ 25 years (%) Prevalence of raised blood pressure among adults aged ≥ 25 years (%) Adults aged ≥ 20 years who are obese (%) Alcohol consumption among adults aged ≥ 15 years (litres of pure alcohol per person per year) Prevalence of smoking any tobacco product among adults aged ≥ 15 years (%) Prevalence of current tobacco use among adolescents aged 13–15 years (%) Prevalence of condom use by adults aged 15–49 years during higher-risk sex (%) Population aged 15–24 years with comprehensive correct knowledge of HIV/AIDS (%)

6. Health systems Health workforce Physicians (per 10 000 population) Nursing and midwifery personnel (per 10 000 population) Dentists (per 10 000 population) Pharmacists (per 10 000 population) Environment and public health professionals (per 10 000 population) Community health workers (per 10 000 population) Psychiatrists (per 10 000 population) Infrastructure and technologies Hospitals (per 100 000 population) Hospital beds (per 10 000 population) Psychiatric beds (per 10 000 population) Computed tomography units (per million population) Radiotherapy units (per million population) Essential medicines Median availability of selected generic medicines in public and private sectors (%) Median consumer price ratio of selected generic medicines in public and private sectors

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d300GlobalHealthRisksTitle.html[11/3/2014 5:18:43 PM] Water and Sanitation-related Dis

Water and Sanitation-related Diseases

(Internet Access required to visit CDC and WHO websites)

These Resources are for information and reference only - you are NOT required to know details of each details of each disease. Important organisms will be dealt with in a later course.

1. Waterborne Diseases Amebiasis (CDC) Buruli Ulcer* (CDC, WHO ) Campylobacter (CDC, WHO) Cholera (CDC, WHO) Cryptosporidiosis (CDC) Cyclosporiasis (CDC) Dracunculasis (guinea-worm disease) (CDC, Carter Center, WHO) Escherichia coli (CDC, WHO) Fascioliasis (CDC, WHO) Giardiasis (CDC) Hepatitis (CDC, WHO) Leptospirosis (CDC, WHO) Norovirus (CDC) Rotavirus (CDC, WHO) Salmonella (CDC, WHO) Schistosomiasis (CDC, WHO, WHO-PPC) Shigellosis (CDC, WHO) Typhoid Fever (CDC, WHO)

2. Sanitation & Hygiene-Related Diseases

Lice (CDC) Lymphatic filariasis (CDC, WHO, Global Alliance to Eliminate LF) Ringworm (CDC, WHO, NIH) Scabies (CDC, WHO) Soil transmitted helminthiasis (CDC, Ascaris, Whipworm, Hookworm, WHO, Children without Worms, WHO-PPC) Trachoma (CDC, WHO, International Trachoma Initiative)

[Note: Many of the waterborne diseases of the previous section may also be associated with inadequate sanitation and hygiene.]

3. Vector or Insect-borne Diseases Associated with Water Arboviral Encephalitides (CDC, WHO) (Eastern Equine Encephalitis, Japanese Encephalitis, La Crosse Encephalitis, St. Louis Encephalitis, Western Equine Encephalitis, West Nile Virus) Dengue/dengue haemorrhagic fever (CDC, WHO) Malaria (CDC, WHO) Onchocerciasis (CDC, WHO) Rift Valley Fever (CDC, WHO)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d350Diseases.html[11/3/2014 5:18:44 PM] Water and Sanitation-related Dis

Yellow Fever (CDC, WHO)

4. Neglected Tropical Diseases associated with water

Buruli Ulcer (CDC, WHO) - According to the World Health Organization, Buruli Ulcer is believed to be present within environments (for example, small aquatic animals, biofilms) from where it can be spread to humans by an unknown m Dengue/dengue haemorrhagic fever(CDC, WHO) Dracunculiasis (guinea-worm disease)** (CDC, Carter Center, WHO) Fascioliasis (CDC, WHO) Lymphatic filariasis (CDC, WHO, Global Alliance to Eliminate LF) Onchocerciasis (CDC, WHO) Schistosomiasis (CDC, WHO, WHO-PPC) Trachoma (CDC, WHO, International Trachoma Initiative)

Modified from: Center for Disease Control, USA http://www.cdc.gov/healthywater/wash_diseases.html

Extra Reading Materials - not required reading, just well-written, semi-technical books and videos.

For an interesting account of the effects of microorganisms on history and health of peoples, see "Guns, Germs and Steel" by Jared Diamond and the Public Broadcasting Service TV program of the same name (Internet Access required)

For an old, but still very relevant, treatment of diseases and their possible emergence and re-emergence see "The Coming Plague" by Laurie Garrett. Published 1995 by Penguin Books

Review: "Unpurified drinking water. Improper use of antibiotics. Local warfare. Massive refugee migration. Changing social and environmental conditions around the world have fostered the spread of new and potentially devastating viruses and diseases—HIV, Lassa, Ebola, and others. Laurie Garrett takes you on a fifty-year journey through the world's battles with microbes and examines the worldwide conditions that have culminated in recurrent outbreaks of newly discovered diseases, epidemics of diseases migrating to new areas, and mutated old diseases that are no longer curable."

From: http://www.goodreads.com/book/show/46722.The_Coming_Plague (Internet Access required)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d350Diseases.html[11/3/2014 5:18:44 PM] Water and Sanitation-related Dis

Modern Water Treatment Systems More Recent Developments in Water Treatment

Water treatment originally focused on improving the aesthetic qualities of drinking water. Methods to improve the taste and odor of drinking water were recorded as early as 4000 B.C. Ancient Sanskrit and Greek writings recommended water treatment methods such as filtering through charcoal, exposing to sunlight, boiling, and straining. Visible cloudiness (later termed turbidity) was the driving force behind the earliest water treatments, as many source waters contained particles that had an objectionable taste and appearance. To clarify water, the Egyptians reportedly used the chemical alum as early as 1500 BCE to cause suspended particles to settle out of water. During the 1700s, filtration was established as an effective means of removing particles from water, although the degree of clarity achieved was not measurable at that time.

By the early 1800s, slow sand filtration was beginning to be used regularly in Europe. During the mid to late 1800s, scientists gained a greater understanding of the sources and effects of drinking water contaminants, especially those that were not visible to the naked eye. During the 19th and 20th centuries, water filters for domestic water production were generally divided into slow sand filters and rapid sand filters (also called mechanical filters and American filters). While there were many small-scale water filtration systems prior to 1800, Paisley, Scotland is generally acknowledged as the first city to receive filtered water for an entire town. The Paisley filter began operation in 1804 and was an early type of slow sand filter. Throughout the 1800s, hundreds of slow sand filters were constructed in the UK and on the European continent. An intermittent slow sand filter was constructed and operated at Lawrence, Massachusetts in 1893 due to continuing typhoid fever epidemics caused by sewage contamination of the water supply. The first continuously operating slow sand filter was designed for the city of Albany, New York in 1897 In 1855, epidemiologist Dr. John Snow proved that cholera was a waterborne disease by linking an outbreak of illness in London to a public well that was contaminated by sewage. In the late 1880s, Louis Pasteur demonstrated the “germ theory” of disease, which explained how microscopic organisms (microbes) could transmit disease through media like water.

During the late nineteenth and early twentieth centuries, concerns regarding drinking water quality continued to focus mostly on disease-causing microbes (pathogens) in public water supplies. Scientists discovered that turbidity was not only an aesthetic problem; particles in source water, such as fecal matter, could harbor pathogens. As a result, the design of most drinking water treatment systems built in the U.S. during the early 1900s was driven by the need to reduce turbidity, thereby removing microbial contaminants that were causing typhoid, dysentery, and cholera epidemics. To reduce turbidity, some water systems in U.S. cities (such as Philadelphia) began to use slow sand filtration. While filtration was a fairly effective treatment method for reducing turbidity, it was disinfectants like chlorine that played the largest role in reducing the number of waterborne disease outbreaks in the early 1900s. In 1908, chlorine was used for the first time as a primary disinfectant of drinking water in Jersey City, New Jersey. The use of other disinfectants such as ozone also began in Europe around this time, but were not employed in the U.S. until several decades later. Many of the treatment techniques used today by drinking water plants include methods that have been used for hundreds and even thousands of years (see the diagram below). However, newer treatment techniques (e.g., reverse osmosis and granular activated carbon) are also being employed by some modern drinking water plants.

Recently, the Centers for Disease Control and Prevention and the National Academy of Engineering named water treatment as one of the most significant public health advancements of the 20th Century. Moreover, the number of treatment techniques, and combinations of techniques, developed is expected to increase with time as more complex contaminants are discovered and regulated. It is also expected that the number of systems employing these techniques will increase due to the recent creation of a multi-billion dollar state revolving loan fund that will help water systems, especially those serving small and disadvantaged communities, upgrade or install new treatment facilities. From: EPA The History of Drinking Water Treatment EPA-816-F-00-006 - February 2000

A combination selected from the following processes is used for municipal drinking water treatment worldwide:

Pre-chlorination - for algae control and arresting any biological growth Aeration - along with pre-chlorination for removal of dissolved iron and manganese Coagulation - or flocculation Coagulant aids, also known as polyelectrolytes - to improve coagulation and for thicker floc formation Sedimentation - for solids separation (removal of suspended solids trapped in the floc) Filtration - removing particles from water Desalination - Process of removing salt from the water Disinfection - for killing bacteria.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d360ModernWaterTreatment.html[11/3/2014 5:18:44 PM] Water and Sanitation-related Dis

available that are used by many water utilities (public or private). In addition to the generalized solutions, a number of private companies provide solutions by patenting their technologies. The developed world employs a considerable amount of automation for water and wastewater treatment. The developing nations worldwide use automation along with manual operations. The level of automation is a choice of operators. The aspects that govern the choice of level of automation are capital and operating costs, skills available locally, operators comfort, integration of automation & control with rest of the component of water supply and so on.

See Course 3 for more details

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d360ModernWaterTreatment.html[11/3/2014 5:18:44 PM] Water and Sanitation-related Dis

Sanitation Technologies and Methods

Sanitation Sanitation refers to the safe disposal of human excreta. This entails the hygienic disposal and treatment of human waste to avoid affecting the health of people. Sanitation is an essential part of the Millennium Development Goals. The most affected countries are in the developing world. Population increase in the developing world has posed challenges in the improvement of sanitation. Lack of provisions of basic sanitation is estimated to have contributed to the deaths of approximately 3.5 million people annually from water borne diseases.

The Indus Valley civilization had a system of underground drainage. The main sewer, 1.5 meters deep and 91 cm across, connected to many north-south and east-west sewers. It was made from bricks smoothened and joined together seamlessly. The expert masonry kept the sewer watertight. Drops at regular intervals acted like an automatic cleaning device.

A wooden screen at the end of the drains held back solid wastes. Liquids entered a cess poll made of radial bricks. Tunnels carried the waste liquids to the main channel connecting the dockyard with the river estuary. Commoner houses had baths and drains that emptied into underground soakage jars.

http://www.harappa.com/lothal/14.html (Internet Connection Required)

Ancient Lothal, an ancient Indus port city in the state of Gujarat, India as envisaged by The Archaeological Survey of India.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d370Sanitation.html[11/3/2014 5:18:45 PM] Water and Sanitation-related Dis

Roman cities and Roman villas had elements of sanitation systems, delivering water in the streets of towns such as Pompeii, and building stone and wooden drains to collect and remove wastewater from populated areas - see for instance the Cloaca Maxima into the River Tiber in Rome.

Most Roman apartment houses (insulae) didn't have much in the way of drainage or toilet facilities; or if they did, such facilities tended to exist only on the ground floor. So most apartment dwellers used chamber pots in their own rooms. Private Roman homes, on the other hand, often had latrines. When they existed, they would typically lie near the atrium or kitchen of the domus or villa. Again, if there were no toilet facilities, chamber pots were typically used, and the contents would be dumped periodically into cesspits. As far as public facilities were concerned, urinal pots and public toilets served the public need. In Rome, large urinal pots typically were posted on street corners. Periodically, fullers (the Roman version of a not-so-dry cleaner) would empty them and use the contents in the process of laundering and bleaching togas, tunics, and other clothing. In many Roman cities there were public toilets.

Latrine, Forum or Seaward baths, Sabratha, Libya.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d370Sanitation.html[11/3/2014 5:18:45 PM] Water and Sanitation-related Dis

Roman Sewer, Cologne

From: http://www.sewerhistory.org

Cutaway view of a typical Roman street during the Roman Empire, showing lead water pipes and a central channel for sewage under the pavement.

Perpendicular connections brought sewage from nearby homes and businesses.

From: http://www.sewerhistory.org

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d370Sanitation.html[11/3/2014 5:18:45 PM] Water and Sanitation-related Dis

Roman Toilets at Ephesus From: http://www.sewerhistory.org

Such public toilet facilities were typically just rectangular shaped rooms (some seating as many as 100 people). Arranged along several of the walls of these rooms were long stone benches each with a row of keyhole-shaped openings cut into it. Water running down drains underneath the benches would flush waste away into the sewers. Sponge-sticks were used instead of toilet paper (which, of course, did not exist at this time).

In the Minoan civilization on Crete (3000 to 100 BCE) there is evidence of sanitation;

Pithoi in the ruined town of Knossos, Crete. Items including oak and olive oil (first and second in importance) were stored in these vessels for the trade with Egypt.

The stone slabs of the floor are partially removed to show part of the extensive sewage canal system underneath the whole settlement. Knossos was probably the first European settlement with a well organized water system for incoming clean water, regular waste water disposal (ending up in the gardens outside the settlement) and storm sewage canals for the times of heavy rain.

Knossos was also the first place in Europe where "flush" toilets actually functioned (although the "flush" seems to have come from buckets of water)

From: http://www.sewerhistory.org

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d370Sanitation.html[11/3/2014 5:18:45 PM] Water and Sanitation-related Dis

Sewer structure in the Palace of Knossos in Crete. The palace dates from 1700-1300 BCE. From: http://www.sewerhistory.org

There is little record of other sanitation in most of Europe until the late Middle Ages. Unsanitary conditions and overcrowding were widespread throughout Europe and Asia during the Middle Ages, resulting periodically in cataclysmic pandemics such as the Plague of Justinian (541-42) and the Black Death (1347–1351), which killed tens of millions of people and radically altered societies. Very high infant and child mortality prevailed in Europe throughout medieval times, due not only to deficiencies in sanitation but to an insufficient food supply for a population which had expanded faster than agriculture. This was further complicated by frequent warfare and exploitation of civilians by autocratic rulers.

The late 1800s saw the beginnings of modern-style toilet design, with models following the earth closet, pan closet, and water closet designs. Modern design was complemented by the invention of toilet paper by American Joseph Cayetti in 1857. The main toilet designs were:

1. Earth closet - Dry earth is used to cover waste material for later removal. Henry Moule patented one design in 1869, advertising it as a great improvement over the cesspit.

2. Pan closet - A simple but fairly unsanitary design featuring a basin with a pan at the bottom. This pan could be tipped to discharge its contents into a receptacle.

3. Valve closet - An opening at the bottom of a pan was sealed by a valve. When flushed, the valve opened and water was released into the pan by some mechanism. As noted above, Sir John Harington is credited with designing the first valve closet. Modern airplane toilets are often a version of the valve closet.

4. Hopper closet - This inexpensive design featured an inverted cone as the receptacle, with a squirt of water released for (generally inadequate) flushing. Because of its low cost, it was used mainly by poor people.

5. Wash-out or flush-out water closet - Water was used to seal the drain tube, as in the modern trap. Combined with a flushing mechanism and siphonic action, this evolved into the modern toilet.

Modern Sewage Treatment

Modern Sewage treatment is the process of removing contaminants from wastewater and household sewage, file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d370Sanitation.html[11/3/2014 5:18:45 PM] Water and Sanitation-related Dis

both runoff (effluents), domestic, commercial and institutional. It includes physical, chemical, and biological processes to remove physical, chemical and biological contaminants. Its objective is to produce an environmentally safe fluid waste stream (or treated effluent) and a solid waste (or treated sludge) suitable for disposal or reuse (usually as farm fertilizer). Sewage treatment is the process that removes the majority of the contaminants from wastewater or sewage and produces both a liquid effluent suitable for disposal to the natural environment and a sludge. To be effective, sewage must be conveyed to a treatment plant by appropriate pipes and infrastructure and the process itself must be subject to regulation and controls. Some wastewaters require different and sometimes specialized treatment methods. At the simplest level, treatment of sewage and most wastewaters is carried out through separation of solids from liquids, usually by sedimentation. By progressively converting dissolved material into solids, usually a biological floc, which is then settled out, an effluent stream of increasing purity is produced.

Sewage treatment generally involves three stages, called primary, secondary and tertiary treatment.

Primary treatment consists of temporarily holding the sewage in a quiescent basin where heavy solids can settle to the bottom while oil, grease and lighter solids float to the surface. The settled and floating materials are removed and the remaining liquid may be discharged or subjected to secondary treatment. Secondary treatment removes dissolved and suspended biological matter. Secondary treatment is typically performed by indigenous, waterborne micro-organisms in a managed habitat. Secondary treatment may require a separation process to remove the microorganisms from the treated water prior to discharge or tertiary treatment. Tertiary treatment is sometimes defined as anything more than primary and secondary treatment in order to allow rejection into a highly sensitive or fragile ecosystem (estuaries, low-flow rivers, coral reefs,...). Treated water is sometimes disinfected chemically or physically (for example, by lagoons and microfiltration) prior to discharge into a stream, river, bay, lagoon or wetland, or it can be used for the irrigation of a golf course, green way or park. If it is sufficiently clean, it can also be used for groundwater recharge or agricultural purposes.

There are many processes used at various stages in different kinds of wastewater treatment plants.

They can include:

Pre-treatment Screening Grit removal

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d370Sanitation.html[11/3/2014 5:18:45 PM] Water and Sanitation-related Dis

Flow equalization Fat and grease removal Primary treatment Secondary treatment Activated sludge Aerobic granular sludge Surface-aerated basins (lagoons) Filter beds (oxidizing beds) Constructed wetlands Biological aerated filters Rotating Biological Reactors Membrane bioreactors Secondary sedimentation Tertiary treatment Filtration Lagooning Nutrient removal Nitrogen removal Phosphorus removal Disinfection Odor control Sludge Treatment and Disposal Anaerobic digestion Aerobic digestion Composting Incineration Sludge Disposal

For more details, see http://en.wikipedia.org/wiki/Sewage_treatment and later sections of the course.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d370Sanitation.html[11/3/2014 5:18:45 PM] Water as a Source of Conflict

Water as a Source of Conflict

See http://www.worldwater.org/conflict/list/ (Internet Access Required) from the Pacific Institute for more detail and a searchable list of Water Conflicts

In the listing, 4 conflicts had a religious basis (all between 3000BCE to 681 BCE), about 112 were due to a development dispute, 6 were due to a military goal, 62 were due to use as a military target, 70 were due to use a a military tool, 16 were where water was used a a political tool, and 65 were due to terrorism acts.

Water as Promoter of Peace

Although water can certainly be a source of conflict and even miltary actions, most water conflicts are resolved peacefully This is because of the imprtance of water to both (or all) of the countries, regions, or areas involved in the disputes. A settlement where water continues to be available,

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d410WaterConflict.html[11/3/2014 5:18:45 PM] Water as a Source of Conflict

perhaps with a changed diistribution or entitlement, seems to be the most common outcome of water disputes. In many cases the water source itself is very vulnerable to diversion or deliberate overuse. The key element seems to be the relative strength or power of the disputing parties; where they are similar, the dispute is often settled quickly. Where they are very unequal, it may take much longer if it even happens at all.

Most disputes are very local in scope, even down the level of neighbours disputes over water rights or withdrawals. The list of water conflicts in 2012 from the Water Conflict Chronology website shows that relatively few are large-scale conflicts and most are about local concerns.

During the 2011 Libyan Civil War, forces loyal to dictator Muammar Gaddafi gain control of a water operations center and cut off water Circle of Blue supply to the capital. The system controls Libya’s Great Manmade River—a system of pumps, pipes, and canals that brings water from 2012 Libya Military tool Yes 2012; UPI distant aquifers to Tripoli and other cities. Half the country is left without running water, prompting the UN and neighboring countries to 2011 mobilize tanker ships to deliver water to coastal cities.

Up to 150 schoolgirls are reported sickened by poison in a school water supply in an intentional attack thought to be carried out by 2012 Afghanistan Terrorism Yes Hamid 2012 religious conservatives opposed to the education of women.

2012 Afghanistan Terrorism Yes Seven children are killed by a bomb thought to be aimed at Afghan police and planted at a fresh water spring in Ghor Province. Shah 2012

Military Islamist militants execute militia members defending the Machalgho Dam in eastern Afghanistan. The dam is being developed for irrigation 2012 Afghanistan target; Yes and local power supply. This dispute is one of several surrounding the international waters of Afghanistan, Iran, and Pakistan, which Mashal 2012 Terrorism share several rivers,.

Thousands of farmers in Karnataka try to prevent the release of water from two dams (Krishna Raja Sagar and Kabini) on the Cauvery Circle of Blue Development River. Injuries to protestors and police are reported. The water releases were ordered by the Indian Supreme Court, which required 2012 India Yes 2012; Indian dispute Karnataka to deliver water downstream state of Tamil Nadu despite severe drought. The dispute continues later in the year when Express 2012 Karnataka again halts releases.

Development Scuffles and protests break out around New Delhi during the summer of 2012 as residents surround water delivery trucks and fight over 2012 India Yes Reuters 2012c dispute water. The summer was the hottest in 33 years, leading to extensive energy and water shortages.

Development Violence erupts in the latest event in the dispute between Pakistan and India over the waters of the Indus Basin. Pakistani militants attack India, dispute; and sabotage water systems, flood protection works, and dams in the Wullar Lake region of northern Kashmir. They attack engineers and Ul Hassan 2012 Yes Pakistan Military workers and detonate explosives at the unfinished Tulbul Navigation Lock/Wullar Dam. Pakistan claims the new dam violates the Indus 2012 target Water Treaty by cutting flows to Pakistan.

Brazil’s federal police respond to reports that water used by the indigenous Guarani-Kaiowa tribe was poisoned by nearby landowners Development Associated 2012 Brazil Yes attempting to gain control over disputed land. Since 2009, the dispute has led to the deaths of three tribesmen, who say the water runs dispute Press 2012a through sacred land.

Development Property 2012 Brazil Work on the controversial $13 billion Belo Monte dam is halted after protesters burn buildings at three dam sites. Phys.org 2012 dispute damage

Development Northeastern Brazil sees growing conflicts after severe drought reduces water availability. News agencies report that one person a day is Catholic Online 2012 Brazil Yes dispute being killed from ‘water wars,’ which involve locals fighting over scarce supplies. 2012

Several incidents of protests, injuries, and deaths are reported in regions of Peru where residents oppose large mines because of Reuters Development 2012 Peru Yes concerns over water quality and water rights. Police kill four protestors in clashes over the proposed Canadian-operated $5 billion dollar 2012a;Yeager dispute Minas Conga gold mine. 2012

Development Protests because of concerns over water quality and water rights around the Xstrata Tintaya copper mine lead to two deaths and 50 2012 Peru Yes Reuters 2012b dispute injuries.

Egypt Development Farmers from the Abu Simbel region in Egypt hold over 200 tourists hostage to protest inadequate irrigation water. The farmers captured 2012 Egypt Yes Independent dispute the tourists after they visited nearby monuments, but released them after officials agreed to a temporary release of water. 2012

Public protests over drinking and irrigation water shortages take place across Egypt. Several protests turn violent: in Beni Sueif, one Development Ooska News 2012 Egypt Yes person is killed and many injured during a conflict over irrigation water; in Minya, villagers clash with officials over water shortages and dispute 2012 water pollution; in Fayyoum, hundreds of people protesting water shortages block a highway and set fires.

Somalia, Military Somali Al Shabaab insurgents poison a well and damage water infrastructure near the port city of Kismayo, Somalia. Insurgents are 2012 Yes Wabala 2012 Kenya target fighting against Kenyan peacekeeping troops participating in the African Union mission in Somalia.

Extensive violence over water is reported in Kenya, with more than 100 deaths in clashes between farmers and cattle herders. The AFP 2012– Development conflict is part of a long-running dispute between Pokomo farmers and Orma, semi-nomadic cattle herders, over land and water. The Kenya Yes 2012;Wikipedia 2013 dispute current conflict is being exacerbated by Kenyan and foreign investment in vast tracts of land for food and biofuel cultivation, putting 2013a pressure on local resources. (See also entry in 2001.)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d410WaterConflict.html[11/3/2014 5:18:45 PM] Water as a Source of Conflict

Development 2012 Kenya Yes Violence, including several deaths, occurs during disputes over access to water in the poorest slums around Nairobi, Kenya. Njeru 2012 dispute

Tajikistan, Development Uzbekistan cuts natural gas deliveries to Tajikistan in retaliation over a Tajik hydroelectric dam which Uzbeks say will disrupt water Kozhevnikov 2012 Yes Uzbekistan dispute supplies. Gas flows resumed after a new contract is signed. 2012

Kyrgyzstan, Tajikistan, Tensions escalate over two proposed dams in central Asia: Kambarata-1 in Kyrgyzstan and the Rogun Dam in Tajikistan. These dams Development The Economist 2012 Uzbekistan, No could affect water supplies in the downstream nations of Uzbekistan, Turkmenistan, and Kazakhstan. Uzbekistan’s president, Islam dispute 2012b Turkmenistan, Karimov, says the dams could cause “not just serious confrontation, but even wars.” Kazakhstan

McNeish Sudan, South Development Violence breaks out at water points in the Jamam refugee camp in South Sudan. Médécines Sans Frontières reports that as many as 10 2012 Yes 2012; Ferrie Sudan dispute refugees die every day because of water shortages at refugee camps in South Sudan. 2012

Information is leaked about an alleged secret agreement that would allow Egypt to build an air base in Sudan to attack the Grand Development Egypt, Ethiopian Renaissance Dam (GERD). Egypt is concerned that the dam, under construction in Ethiopia just upstream of Sudan on the Sudan Tribune dispute; 2012 Ethiopia, Yes Blue Nile, would reduce flows into its territory. The news reports, strongly denied by Egypt, claim that Sudan would allow Egypt to launch 2012; Al Military Sudan attacks if diplomatic efforts failed to resolve water sharing between Egypt and Ethiopia. The allegations were based on an internal 2010 Arabiya 2012 target email made available by Wikileaks.

A clash along the border between Dogon villagers from Mali and nomadic Fulani herders from Burkina Faso kills at least 30 people, after Mali, Burkina Development Xinhua News 2012 Yes an earlier agreement to share water and pasture land was revoked. Chaos following a military coup in March is partly responsible for the Faso dispute 2012a breakdown in law and order in Mali.

Mali, Development Protests and violence over water shortages occurred in the capital of Mauritania, Nouakchott. By July 2012, over 70,000 Malian refuges 2012 Yes Taha 2012 Mauritania dispute were seeking asylum in Mauritania, putting pressure on scarce food and water supplies.

Development In August 2012, fighting between two clans in the Lower Jubba region of south Somalia kills at least three people and wounds five. Shabelle Media 2012 Somalia Yes dispute Reports from the village of Waraq (near the border with Kenya) indicate that the dispute began over the ownership of new water wells. Network 2012

Uganda, Development Tensions lead to violence between Uganda and Kenya after Kenyan Pokot herdsmen cross the border seeking water and pasture. In 2012 Yes Bii 2012 Kenya dispute October, the Ugandan government sends 5,000 soldiers to control violence among pastoralists from the two countries.

Violence between farmers and pastoralists expands in Tanzania’s southeastern Rufiji valley, a region hit by drought. A farmer is killed in Development 2012 Tanzania Yes a conflict with a herdsman over access to water in the southern regions of Lindi and Mtwara. Five more people die and many more are Makoye 2012 dispute injured in subsequent violence. According to local sources, violence has worsened during the prolonged drought.

Development Protesters in poor communities of Cape Town, South Africa riot over inadequate water and power. Hundreds burn tires, destroy cars, and Xinhua News 2012 South Africa Yes dispute throw rocks at police in anger over the lack of basic services. 2012b

Military During the Syrian Civil War, the major pipeline delivering water to the city of Aleppo is badly damaged. The city of three million suffers 2012 Syria Yes BBC 2012a target severe shortages of drinking water.

In November, Syrian rebels fighting the government of President Bashar al-Assad overrun government forces and capture the Tishrin Military 2012 Syria Yes hydroelectric dam on the Euphrates River, after days of heavy clashes. The dam supplies electricity to part of Syria and is considered Mroue 2012 target strategically important to the Syrian regime.

Development Violence over access to a water source in Maluku, Indonesia. Rival mobs from two villages attack one another “with sharp weapons, guns 2012 Indonesia Yes Antara 2012 dispute and explosives” causing several deaths and injuries.

For a complete list of the water conflicts from the Pacific Institute, see this page (Local Version) To access the interactive web pages at the Pacific Institute go to the web site at http://worldwater.org/chronology.html (Internet Access Required)

International Treaties on Water

Approximately 261 international watersheds, and an unknown but very large number of transboundary aquifers, cover about one-half of the globe's land surface. Water has created and worsened tensions around the globe, most notoriously in the Middle East, but also throughout Africa and Asia.

The fortunate corollary of water conflict is that water, by its very nature, tends to induce even hostile neighbours to cooperate even as disputes continue over other issues. The evidence tends to favor water as a catalyst for cooperation: organized political bodies have signed 3,600 water-related treaties since AD 805, versus only seven minor international water-related skirmishes (each of which included other non-water issues).

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d410WaterConflict.html[11/3/2014 5:18:45 PM] Water as a Source of Conflict

The UN Food and Agriculture Organization has identified more than 3,600 treaties relating to international water resources dating between AD 805 and 1984, the majority of which deal with some aspect of navigation. Since 1814, states have negotiated a smaller body of treaties which deal with non- navigational issues of water management, flood control, hydropower projects, or allocations for consumptive or non-consumptive uses in international basins. Including only those dating from 1870 and later which deal with water per se, and excluding those which deal only with boundaries, navigation, or fishing rights, the authors have collected full and partial texts of 145 treaties in a Transboundary Freshwater Dispute Database at the University of Alabama. The collection and translation efforts continue in an ongoing project of the Department of Geography and the Center for Freshwater Studies, in conjunction with projects funded by the World Bank and the US Institute of Peace. Table 1 lists the treaties in the Database chronologically.

Modified from : Patterns in International Water Resource Treaties:The Transboundary Freshwater Dispute Database by Jesse H. Hamner and Aaron T. Wolf. Published in: Colorado Journal of International Environmental Law and Policy. 1997 Yearbook, 1998.

Local Version of the Paper

UNESCO and Green Cross contributed the publication below (a local version) to the World Water Assessment Programme.

"From Potential Conflict to Cooperation Potential: Water for Peace" : Contribution of the International Hydrological Programme and Green Cross International to the World Water Assessment Programme (WWAP) (Local Version)

Summary:

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d410WaterConflict.html[11/3/2014 5:18:45 PM] A selected list of Global Databa

A selected list of Global Databases relevant to the Water Health Programme

Click on each image to go to the main page for the website (this will open in a new window) (Internet Access Required)

A very large list of many databases that offer access to environmental data (Internet Access Required)

The World Resource Institute uses data from many sources to produce many relevant maps, graphs and publications (Internet Access Required)

The World Health Organization has many relevant datasets and publications at http://www.who.int/research/en/ (Internet Access Required)

and

Water, sanitation and health databases at http://www.who.int/water_sanitation_health/database/en/ (Internet Access Required)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d500ListofDatabases.html[11/3/2014 5:18:46 PM] A selected list of Global Databa

The Pacific Institute has many articles, maps and databases on topics related to water (Internet Access Required)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d500ListofDatabases.html[11/3/2014 5:18:46 PM] Other Sources of Data

Other Sources of Data: Waterbase

A large amount of global data is available for download. All data can be used in the MapWindow/SWAT interface tools MWSWAT and MWSWAT 2009 ,the SWAT visualization tools SWATPlot and SWATGraph and the MapWindow/AGNPS interface tool MWAGNPS. These tools are used for predictive modeling and decision support for water management (Internet Access Required)

(all software is freely downloadable from www.waterbase.org - (Internet Access Required)

Waterbase Data Sets:

The main data inputs for hydrological modelling are digital elevation, land use, and soil. These are the sources our data is currently based on:

SRTM 90m Digital Elevation Data

USGS Global Land Cover Characterization (GLCC) database

FAO/UNESCO Soil Map of the World and Derived Soil Properties

Data Downloads (Internet Access Required)

A large amount of global data is available for download.

World Data Grids

This is a MapWindow project contained in a zip archive that allows you to graphically select the DEMs, landuse, and soil maps that you need for your location. Just unzip the archive and open the project file World_Data_Grids.mwprj in MapWindow.

Digital Elevation Maps (DEMs)

DEMs for most of the world are available from CGIAR-CSI. The quantity of data for the world is very large, but our geo- processing guide (see the documents page) explains how to select the files you need.

Landuse Maps

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d501Waterbase.html[11/3/2014 5:18:46 PM] Other Sources of Data

Landuse maps for most of the world are available from WaterBase. They come in the form of zip files containing 1 or more tiles for each continent. They come in two resolutions, the originals at approximately 400 meters (at the equator) and the resampled at 800 meters. The first are a little more accurate but the they take some time to load and minipulate in MapWindow. You may prefer to use the resampled ones at least while you are learning or experimenting.

Africa (original) Africa (resampled) Australia/Pacific (original) Australia/Pacific (resampled) Europe/Asia (original) Europe/Asia (resampled) North America (original) North America (resampled) South America (original) South America (resampled)

Soil Maps

Soil maps for most of the world are available from WaterBase. They come in the form of zip files containing 1 or more tiles for each continent.

Africa Australia/Pacific Europe/Asia North America South America

Also available are some notes and a readme file from the FAO, the source of the soil data.

Weather Data

Global weather data is now available from the SWAT website, and WaterBase also offers a special program for detecting and compensating for missing dates in that data. The SWAT data is more extensive than the data previously offered by WaterBase.

Global River Basins file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d501Waterbase.html[11/3/2014 5:18:46 PM] Other Sources of Data

Shape files for river basins across the world are available from WaterBase, divided into continents:

Africa Asia Australasia Europe North America South America

Digital Elevation Maps (DEMs)

DEMs for most of the world are available from CGIAR-CSI (Internet Access Required). The quantity of data for the world is very large, but the Waterbase geo-processing guide (see the documents page) explains how to select the files you need.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d501Waterbase.html[11/3/2014 5:18:46 PM] Gapminder World

Gapminder World

This graphic shows the Life Expectancy versus the Per Capita Income (converted to $US) for the countries of the world

Click the graphic above to download the large, full-sized Adobe Acrobat file (suitable for printing) (Internet Access Required)

If you have an internet connection, you can go to Gapminder World (Internet Access Required) and look at many other comparisons,

Some interesting ones are: Wealth & Health of Nations: This graph shows how long people live and how much money they earn. Click the play button to see how countries have developed since 1800.

People killed in floods: The size of the bubbles shows the number of people killed in floods during the given year.

CO2 emissions since 1820: In 1820, at the dawn of the Industrial Revolution, United Kingdom emitted most CO2 - both per person and in total emissions. See how USA becomes the largest emitter of CO2 from 1900 onwards.

Smaller families and longer lives: In the 1950s, most countries in Latin America, Asia and Africa had low life

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d510GapMinder.html[11/3/2014 5:18:47 PM] Gapminder World

expectancy and high birth rates; in most cases, more than 5 children per women. Only five decades later, most of those countries have less than three children per woman, and much longer lives.

You can choose which data you want to plot and try out different datasets to see the results.

On this page is a list of over 500 data sets that can be used to produce Gapminder graphics

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d510GapMinder.html[11/3/2014 5:18:47 PM] Water Management

Water Management

To effectively manage water, many different skill sets are needed, but they were often located in different agencies.

The skills include:

· Engineering · Computer Science – Databases, Modeling and Simulation · Biology

· Management Sciences · Chemistry

· Agriculture · Microbiology

· Sociology · Soil Science

· Ecology · Climatology

· Economics · Hydrology

· Aquatic Toxicology · Hydrogeology

· Environmental Sciences · Remote Sensing

· Legal & Regulatory · Geographic Information Systems

· Governance and Political Science · Cartography

The evolution of water management has been the gradual integration of people withy these skill sets, coupled with an increasing involvement of society as a whole in the decision making process that balances the competing interests in water.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d800WaterManagementTitle.html[11/3/2014 5:18:47 PM] Water Management

Water Management

Integrated Water Resource Management

Integrated Water Resources Management (IWRM) is a process which promotes the coordinated development and management of water, land and related resources in order to maximise economic and social welfare in an equitable manner without compromising the sustainability of vital ecosystems and the environment.

IWRM helps to protect the world’s environment, foster economic growth and sustainable agricultural development, promote democratic participation in governance, and improve human health. Worldwide, water policy and management are beginning to reflect the fundamentally interconnected nature of hydrological resources, and IWRM is emerging as an accepted alternative to the sector-by-sector, top-down management style that has dominated in the past.

The basis of IWRM is that the many different uses of finite water resources are interdependent. High irrigation demands and polluted drainage flows from agriculture mean less freshwater for drinking or industrial use; contaminated municipal and industrial wastewater pollutes rivers and threatens ecosystems; if water has to be left in a river to protect fisheries and ecosystems, less can be diverted to grow crops. There are plenty more examples of the basic theme that unregulated use of scarce water resources is wasteful and inherently unsustainable.

Diagram of IWRM Interactions

The diagram is an attempt to show the factors that impact developing an IWRM plan in a watershed or drainage basin.

The four main areas to be considered are:

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d810WaterManagement.html[11/3/2014 5:18:47 PM] Water Management

1. The hydrologic cycle - the physical aspects of water transport and movement in the system 2. Watershed and land use - all the activities in the watershed that affect water cycling, use and quality 3. Economics, social interactions and institutons - human interventions, social and legal aspects,waste treatment, water control measures,and others 4. External Impacts such as global climate change, water transfers (including virtual water imported or exported in food and other products), and atmospheric pollution

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d810WaterManagement.html[11/3/2014 5:18:47 PM] Water Management

Water Management

Recent Developments in Water Management

In the 20th Century, water management and sanitation developed into a complex interacting system in the industrialized countries. It started as a set of individual management processes for the various resources (water supply, purification and distribution, and waste disposal systems), but it soon became evident that these resources needed to be coordinated to be most effective and safe. During the past 80 years an evolving integration of these processes, and the institutions operating them, has happened. More recently, the concept of Integrated Water Resource Management (IWRM) has come to be the dominant theoretical basis for integrating and managing all of the complex set of resources, processes, governance structures, social and legal issues that surround water and sanitation management The usual scale of IWRM is at the watershed, or drainage basin scale.

The evolution of the concept of IWRM came from observations that many aspects of water protection, treatment, distribution, sewage and waste treatment, water quality, and legal protections and rights to water were scattered amongst many different agencies, government and municipal departments,

There are four main stages in the evolution of IWRM. They occur along an uninterrupted pathway and overlap considerably.

For the sake of convenience, we will deal with each period separately.

1. The Sectoral Approach - 1820 to 1950s

2. The Cooperative Approach - 1960s and 1970s

3. Management-oriented IWRM - 1980s

4. Goal-oriented IWRM - 1990s to present

1. The Sectoral Approach: Discussion

In the earliest examples of water planning, no sectors really existed -- there were only private or public bodies responsible for delivering water to citizens. As different interest groups were formed (government, consumers, regulators, companies, etc.), responsibilities began to be shared and each sector's respective part in managing the water supply began to be defined.

Very early on, different agencies and institutions became responsible for:

Planning and implementation processes, Activities and tasks (such as water storage, transmission, distribution, allocation), Physical and construction measures (water canals, dams, reservoirs), Legal and economic instruments such as regulations and incentives, Institutional and organizational requirements.

They began to cooperate in some rudimentary form.

Eventually these tasks and responsibilities devolved to particular agencies, but it became increasingly clear that cooperation was necessary to ensure a safe and plentiful supply of water.

2. The Cooperative Approach: Discussion

In the 1960s and 1970s, cooperative efforts increased until it became clear that more organized cooperation was required to protect the water supply, distribute the water and monitor and regulate the water quality. In the developed world, these efforts led to agencies becoming specialized (e.g. government environment agencies or ministries for monitoring and regulation) and cooperating with the other groups (the private sector, municipalities, states, etc.) who, in many cases, actually provided and distributed the water.

Gradually, the concept of an integration of many of the functions surrounding the supply of water (for all purposes, not just for drinking water) came into being. It began as a realization that to manage water effectively, one needs to look at a broader scale picture -- that of the watershed (or drainage area of the river or lake) that supplies the water. Where groundwater was the primary or a substantial component, the recharge area (where water enters the groundwater system) and any other region that could affect

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d820IWRM.html[11/3/2014 5:18:47 PM] Water Management

the quantity and quality of the groundwater, must also be considered.

3. Management-Oriented IWRM: Discussion

There are many examples of early attempts at IWRM. Some recommendations for Canadian policies were developed by Pearse et al. (1985). The “key” principles were:

· A watershed plan sufficiently comprehensive to take into account all uses of the water system and other activities that affect water flow and quality.

· Information about the watershed’s full hydrological regime.

· An analytical system, or model, capable of revealing the full range of impacts that would be produced by particular uses and developments in the watershed.

· Specified management objectives for the watershed, with criteria for assessing management alternatives in an objective and unbiased way.

· Participation of all relevant regulatory agencies.

· Provisions for public participation in determining objectives and in making management decisions.

Note the emphasis on watersheds, hydrology, analytical models, management and participation

4. Goal-Oriented IWRM: Discussion

A typical set of goals was given by Heathcote (2002):

· To develop a consensus-based vision of ideal water resources conditions for the area of interest.

· To measure the distance between current and ideal conditions, and thus define one or more water management problems, based on consensus among stakeholders.

· To develop and apply tools for water resources decision making, including demonstration projects, computer simulation models, conflict resolution tools, data management and sharing, and so on.

· To identify appropriate management actions to resolve observed problems.

· To assign responsibility for actions and costs for remedial measures.

· To agree upon acceptable timelines for implementation of management actions.

· To monitor the degree of implementation of management actions and progress toward water resources goals.

· To build the capacity of regional stakeholders for collaborative, consensus-based management of water resources.

· To build institutional capacity to work across jurisdictional, disciplinary, and sector boundaries.

· To achieve measurable progress toward improved water resources conditions.

Why IWRM?

Recently, many researchers and practitioners have suggested modifications, relabeling, additions, changes, updates, and specific regional applications to the basic concept of IWRM. A great deal of misunderstanding about what IWRM really is have proliferated or have been deliberately promulgated. It is NOT a prescriptive set of procedures that, if followed, will result in a management program for all situations. That is an extremely naive view of IWRM and if followed, is almost bound to result in failure to some degree.

Rather, IWRM is a set of flexible and adaptable principles (see Heathcote, 2002 above for an example) that guide in the development of an individual Integrated plan for managing water resources (and all their associated features such as land management, community action, legal and social frameworks, etc.).

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d820IWRM.html[11/3/2014 5:18:47 PM] Water Management

There are legitimate criticisms of IWRM based on the difficulties involved (see wh001mo001c001d850IWRMEXTRA.html) and Butterworth, J.; Warner, J.; Moriarty, P.; Smits, S. and Batchelor, C. 2010. "Finding practical approaches to Integrated Water Resources Management". www.water-alternatives.org Volume 3 Issue 1 - Local version: IWRMconcepts and practice.pdf.

The answer to "Why IWRM?" may best be explained by considering "What are the other choices?". Most other choices either fall short or are variants of IWRM in some other guise.

The relevance of the concepts behind IWRM can best be judged by the number of papers published about it, the groups of academics who have attempted to redefine it according to their own views, the many attempts to incorporate it under another banner so that particular practitioners can gain control of it and its very widespread acceptance in the field.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d820IWRM.html[11/3/2014 5:18:47 PM] Towards IWRM

Towards IWRM

Overview of Procedures for Implementing an IWRM Plan

How can IWRM be accomplished?

Four main areas are as important as data gathering and modelling exercises in IWRM.

These areas are: · Capacity Building · Information Exchange · An Enabling Environment · Cooperative Decision Making -- Involving Society in the IWRM Planning Process: Discussion

The goal of watershed management is to plan and work toward an environmentally and economically healthy watershed that benefits all who have a stake in it. The first step is to identify and involve the "right" people.All people with a stake in the watershed (stakeholders) should feel welcome to become a partner. Consider the following three distinct groups: · Those who are BOTH affected by and interested in watershed protection · Those who ARE affected, but NOT interested · Those who are NOT affected, but ARE interested

One way to involve society is to produce a matrix of available information and data and identify gaps. Fill those gaps if possible by:

Capacity Building Acquiring Information/Data: Available Information Local Information Indigenous Knowledge Enabling legislation and regulation

Build a Common Purpose

A carefully worded statement serves as a standard for decision making and measuring progress, and provides motivation for high quality. Make sure all partners are comfortable with the statement. Steps in developing a statement of purpose include:

Asking for ideas from all partners Discussing the ideas and drafting a statement Revising a draft based on discussion Writing a final statement based on consensus Soliciting statements of commitment from all partners

This process may not be easy and will take time. Potential conflicts need to be discussed and resolved. Remember, it is important to keep the statement general enough to encourage widespread support, but specific enough to identify goals and measure progress.

Gathering Information About the Area of the IWRM Plan

Some partners who can assist in data and information gathering and many other aspects of the IWRM planning process are:

Landowners Homeowners Local businesses Developers Recreational users Government agencies Elected officials file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d830TowardsIWRM.html[11/3/2014 5:18:47 PM] Towards IWRM

Media Teachers Civic groups Conservation groups Environmentalists Church groups Youth groups Others .

Successful IWRM Planning

All participants agree to and share a common set of goals for the study area. These are defined in advance and modified as required. Information and data are accessible and provided to all participants. There is a well-understood “core” of basic information, shared by all, about all aspects of the study area. Capacity building is targeted towards ensuring that all participants share a common set of basic knowledge, data and capabilities, especially in areas where they are not specialists. Genuine participatory decision making is the rule, not the exception. Conflict resolution procedures are available and used. Reporting is a collaborative process. Management and implementation are also collaborative. There is “targeted” capacity building and a “shared knowledge base”. There is an enabling environment. There is effective information exchange. There are processes for cooperative decision making and management.

Potential Benefits of IWRM

Consensus-based water management decisions with high implementation success Significantly improved community capacity for water resources decision making. Significantly improved institutional capacity for multi-stakeholder/multi-disciplinary water management. Reduced costs for governments, because increased partnerships share costs across stakeholder groups. Measurable and sustainable water resources improvements, as a result of community consensus as to a “best” course of action, including responsibilities and costs. A planning and management process that is ongoing, adaptive and iterative.

Summary of the Goals of IWRM · To develop a consensus-based vision of ideal water resources conditions for the area of interest. · To measure the distance between current and ideal conditions and, thus, define one or more water management problems based on consensus among stakeholders. · To develop and apply tools for water resources decision making including demonstration projects, computer simulation models, conflict resolution tools, data management and sharing, and so on. · To identify appropriate management actions to resolve observed problems. · To assign responsibility for actions and costs for remedial measures. · To agree upon acceptable timelines for implementation of management actions. · To monitor the degree of implementation of management actions and progress toward water resources goals. · To build the capacity of regional stakeholders for collaborative, consensus-based management of water resources. · To build institutional capacity to work across jurisdictional, disciplinary and sector boundaries. · To achieve measurable progress toward improved water resources conditions

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d830TowardsIWRM.html[11/3/2014 5:18:47 PM] Progress towards IWRM

Progress towards IWRM?

IWRM has been a qualified success.

Studies reveal that:

· IWRM principles are internationally accepted but not yet truly applied to drinking water supply and sanitation). · Water source and catchment conservation is gaining recognition but requires further work. · True stakeholder involvement in water allocation decision making remains limited. · The framework to allow management at the lowest appropriate level is often not available. · Capacity building is promoted but not at all levels, and its effectiveness is not monitored. · Stakeholder involvement is growing, but is still too limited and too narrow in focus. · Efficient water use is gaining attention but requires much greater emphasis. · Water is increasingly viewed as having an economic and social value. · Striking a gender balance is often perceived to mean enhancing women’s involvement.

The identified Conditions for Success of IWRM were: There is a set of recurring conditions or decisions that are associated with successful IWRM projects. Not all successful projects have all of these conditions, but many of them are shared by many successful projects. They are:

· All participants agree to and share a common set of goals for the study area. These are defined in advance and modified as required. · Information and data are accessible and provided to all participants. · There is a well-understood “core” of basic information, shared by all, about all aspects of the study area. · Capacity building is targeted towards ensuring that all participants share a common set of basic knowledge, data and capabilities, especially in areas where they are not specialists. · Genuine participatory decision making is the rule, not the exception. · Conflict resolution procedures are available and used. · Reporting is a collaborative process. · Management and implementation are also collaborative

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d835ProgressIWRM.html[11/3/2014 5:18:48 PM] Water Management

Water Management

Integrated Water Resource Management

The process of IWRM has been described in many documents from many different sources, but the general consensus of most is based on the broadly accepted definition of IWRM as:

"a process which promotes the coordinated development and management of water, land and related resources in order to maximize economic and social welfare in an equitable manner without compromising the sustainability of vital ecosystems and the environment " The Global Water Partnership (Internet Access Required)

1. “Fresh water is a finite and vulnerable resource, essential to sustain life, development, and the environment. . .”

2. “Water development and management should be based on a participatory approach, involving users, planners, and policy-makers at all levels. . .”

3. “Women play a central part in the provision, management, and safeguarding of water. . .”

4. “Water has an economic value in all its competing uses and should be recognized as an economic good. . . .”

The emphasis of the Dublin Statement on the economic value of water rather than water as a universal right is highly contested by NGOs and human rights activists. Up till today it is still the only binding UN document that makes a statement on the issue. In November 2002, however, the UN Committee on Economic, Social and Cultural Rights (Internet Access Required) adopted General Comment No. 15, which was formulated by experts as a comment on articles 11 and 12 of the International Covenant on Economic, Social and Cultural Rights. In this comment, water is recognized not only as a limited natural resource and a public good but also as a human right. This step - adopting General Comment No. 15 - is seen as a decisive step towards the recognition of water as universal right, although the document has no legally binding power.

Integrated Water Resources Management (IWRM) is a process which promotes the coordinated development and management of water, land and related resources in order to maximize economic and social welfare in an equitable manner without compromising the sustainability of vital ecosystems and the environment.

Diagram of IWRM Interactions

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d840IWRM1.html[11/3/2014 5:18:48 PM] Water Management

The diagram is an attempt to show the factors that impact developing an IWRM plan in a watershed or drainage basin.

The four main areas to be considered are:

1. The hydrologic cycle - the physical aspects of water transport and movement in the system 2. Watershed and land use - all the activities in the watershed that affect water cycling, use and quality 3. Economics, social interactions and institutions - human interventions, social and legal aspects, waste treatment, water control measures, and others 4. External Impacts such as global climate change, water transfers (including virtual water imported or exported in food and other products), and atmospheric pollution

There is an interesting summary of web-based documentation on IWRM done by Thelwall et al, that looks at all mentions of IWRM and related terms and determines the most referenced sites.

They list the Top 30 linked pages

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d840IWRM1.html[11/3/2014 5:18:48 PM] Water Management

Most are United Nations, NGO or government sites (like the EPA in the USA) with only a few commercial or private sector sites in the top 30. They also analyzed the interlinkages between the Top 50 sites:

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d840IWRM1.html[11/3/2014 5:18:48 PM] Water Management

Again, it is clear that a few sites "dominate" with many other sites linking to only a few "key" or "popular" sites. This is interesting since it can imply that:

These top sites are the best since everyone links to them or... Everyone copies everybody else's links or.... Looking at links does not quantify the "quality" of the information or ..... The "Top" sites started first or .... The top sites agreed to "swap" links to enhance their "Google" rating or ..... The Top sites are simply bigger with more opportunities for "in-linking" or ... Many other possibilities!

A simple map of links has also been done for the entire Internet at Lumeta Corp (Internet Access Required) Here is one such map from Lumeta Corporation:

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d840IWRM1.html[11/3/2014 5:18:48 PM] Water Management

This is simply a map of linkages, with no assessment of the number of linkages within pages - but it does show the presence of massive concentrations of internet sites in certain places and regions (IP numbers)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d840IWRM1.html[11/3/2014 5:18:48 PM] IWRM Problems and Issues

IWRM Problems and Issues

From: . Butterworth, J.; Warner, J.; Moriarty, P.; Smits, S. and Batchelor, C. 2010. "Finding practical approaches to Integrated Water Resources Management". www.water-alternatives.org Volume 3 Issue 1

Local version: IWRMconcepts and practice.pdf

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d850IWRMEXTRA.html[11/3/2014 5:18:48 PM] Distribution of Water on the Ear

Summary

We have seen the central importance of water to life on Earth and how it is distributed and cycled through the atmospher, fresh and sea water.

It is an unfortunate fact that only a very small percentage of water is fresh water available for human consumption and use.

The population is increasing to 9 billion by 2050 and large parts of the Earth, mainly developing countries, will be under even more severe water stress than they are now.

Today, issues of governance, management and equity are extremely important to ensure efficient and equitable delivery of safe water and sanitation thoughout the world. It is estimated that for $40 to $50 billion dollars per year, safe water could be provided to all the world's population. For some perspective, in 2013/2014 the world will spend $1747 billion on military budgets and $66 billion on pet foods.

As a demonstration of the complex interactions involving water, Shell Oil recently completed a study originated in 2009 of the inter-relationships between water, energy and food (the Water-Energy-Food Nexus) and initially found over 300 iteractions. They simplified these to 100 interactions and the diagram below shows this Nexus.

Shell personnel commented that "Sectors tend to look at only at their own resources. There's an assumption that there will be enough of the other things you need to develop your thing. That was the reason to start working on the Nexus". Working with Eric Berlow (an ecologist and network expert from Berkeley, U. California) they developed a picture of these interactions.

By their estimates, by 2050 the gap between energy supply and demand could be as big as the total energy industry output in 2000. By 2030, water supply could fall short of demand by 40%. By 2030, the food required to feed the world might be up by 50% with demand for beef (highly water- and land-intensive) up by 80%.

Even if the numbers are not certain, this still very clearly shows that water issues and supplies cannot be viewed in isolation and that a complex interacting web of issues related to water, food, and energy need consideration -- and action!

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d890Summary.html[11/3/2014 5:18:49 PM] Distribution of Water on the Ear

From: Shell Oil and WIRED magazine - UK Edition - September 2014

To provide a counterpoint to the scenarios described above, we must remember and acknowledge the tremendous progress that has been made in the past few decades.

According to Peter Gleick of the Pacific Institute, although we still need to address issues of water supply and quality for a large number of people, the situation today is much improved.

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d890Summary.html[11/3/2014 5:18:49 PM] Distribution of Water on the Ear

In a talk at the Water Institute at the University of Waterloo, he set forth his ideas on where we have been, where we are today and what we need to do to address the outstanding issues of water and climate change.

It is available on YouTube at:

https://www.youtube.com/watch?v=ponjGxp7twk&list=PLawkBQ15NDEkajDjQxgbRZlqXCKXbvtJJ&index=5 (Internet Access required = Right-click and "Open in New window" for the best experience for most browsers)

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d890Summary.html[11/3/2014 5:18:49 PM] References List

Reference Materials

The Concept and Discussion Pages are identical

Bibliography

On-line Bibliography for IWRM

Search for "UN Water Learning Centre" go to "Papers" in the left-hand section and you can then search that IWRM database for any one of hundreds of keywords.

Go directly there now (Internet Access Required)

A local version of the listing of tags is here. This version may not be completely up-to-date.

The reason for this convoluted process is that Mendeley does not allow searches on all of the tags, only on a predetermined set of popular tags.

Extra Reading Materials on the CD - A selected List

Disease

World Health Statistics - WHO 2012

Water-based diseases - Bachurova - IWA

Global health Risks - WHO 2010

Which Came First: Burden of Infectious Disease or Poverty? - Chase - PLOS 2010

Bibliography of Safe Water, Small Scale and Household Water Treatment - Microsoft Word

Drinking Water

Drinking Water Quality - Parker - IWA

Bibliography of Safe Water, Small Scale and Household Water Treatment - Microsoft Word

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d950ReferenceMaterial.html[11/3/2014 5:18:49 PM] References List

History

A Brief History of Water and Health - Parker - IWA

Ancient Water Technologies - Mays - Springer

Building terrestrial planets Morbidelli, Lunine, O'Brien, Raymond and Walsh

Water Gods – From Wikipedia

Health

Health Impact Assessment for Sustainable Water Management - Parker - IWA

Health-related Risk Assessment - Parker - IWA

Bibliography of Safe Water, Small Scale and Household Water Treatment - Microsoft Word

IWRM

The Dublin Statement

Web Issue Analysis: An Integrated Water Resource Management Case Study - Thelwall, Vann and Fairclough

Practical Approaches to IWRM - Butterworth, Warner, Moriarty, Smits and Batchelor - PLOS 2010

IWRM at a Glance - GWP

IWRM Background - For sustainable use of water - Snellen and Schrevel 2004

IWRM Brochure - Guidelines at a River basin Level - WWAP - UINESCO

Finding Practical Approaches to Integrated Water Resources Management - Butterworth, Warner, Moriarty, Smits and Batchelor

Water Conflict Chronology Timeline - Pacific Institute

Water for Peace - WWAP - UNESCO

Patterns in International Water Resource Treaties - Hamner and Wolf 1998

The Millenium Development Goals Report 2012 - UN

Safe Water for the Community - CDC

Water for Peace - WWAP - UNESCO

Sanitation

Sanitation - Miller -IWA

Helping Sanitation Enter the Era of Sustainability - Miller - IWA

Bibliography of Safe Water, Small Scale and Household Water Treatment - Microsoft Word

Water Quality

Water Quality and Purity - Parker - IWA

Bibliography of Safe Water, Small Scale and Household Water Treatment - Microsoft Word

file:///F|/Dropbox/WaterHealthNewFinal/Course1/discussion/wh001mo001c001d950ReferenceMaterial.html[11/3/2014 5:18:49 PM] WLC Template

Course 2: WATER-RELATED IMPACTS ON HEALTH PRINCIPLES, METHODS AND APPLICATIONS

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M000C001TitlePage.htm[11/3/2014 5:19:40 PM] WLC Template

Introduction

"health, which is a state of complete physical, mental and social wellbeing, and not merely the absence of disease or infirmity, is a fundamental human right...." (1978 Declaration of Alma-Ata)

1. Water-related impacts on health and the relationships between water and health and well-being can be viewed through separate macro lenses or within spheres of the following,

The User of Water - individual and community health and well being

The Needs and Usage of Water - drinking water sanitation and hygiene, food farming and agriculture, industry and commercial processing and manufacturing, and other

The Quality of Water - its physical, chemical and biological properties and constitutents

The Availability and Accessibility of Water - source quantity and sustainability of water that is surface water groundwater rain water

2. Where overlap of the lenses (spheres) occurs there is significant potential for water-related impacts on health and well being.

3. An integrated approach incorporating the determinants of health and the principles of needs and risk assessment is taught learned and applied by focusing educational materials and efforts on where there is overlap and convergence of the above spheres.

4. Water-related impacts on health may be beneficial or harmful and are inextricably dependent on the quality of water available for use by the user.

5. Immediate and potentially life threatening needs for health and safety and risks of acute and chronic illness and disease must be prioritized and mitigated, notwithstanding economic social and cultural aspects contibuting to water-related impacts on health and well being.

This part of the course focuses specifically on the relationship between water quality and exposure to contaminants in water and the prevention of water-related illness and disease.

BACKGROUND AND RATIONALE FOR AN INTEGRATED APPROACH TO WATER AND HEALTH

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M001C001WRIHIntroduction.htm[11/3/2014 5:19:40 PM] WLC Template

Problem Formulation and Scoping the Current Situation

Information Gathering - Situational Analysis

Scoping the current situation and identifying the problems and the issues, in terms of the vulnerability, susceptibility, ethics, gaps and limitations pertaining to

observed health effects in the population, identified hazards environmental exposures and known and suspected risk factors environmental and social modifying factors influencing risks and impacts on outcomes

Consideration of medical approach versus environmental health approach to addressing water related impacts on health. Applications to water related impacts on health are addressed later in the Course in those sections dealing with epidemiology and human health and environmental risk assessment and the section dealing with social surveys.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M001C003WRIHIntroductionQuestionnaires.htm[11/3/2014 5:19:41 PM] WLC Template

Water Quality And Water Pollution The quality of water depends on the water source, its constituent properties and the geographical location and season, the users and use of the water, as a receiving environment wastes and releases from polluting sources. Safe water for drinking and personal hygiene and other potable uses, including food production and preparation, is necessary for the prevention of human disease and illness. Uses of water, other than for drinking water, are numerous and may have different requirements for need for stringency of the water quality.

Five Types of Water Sources: (reviewed in previous course)

Surface waters - Water collecting on the surface or in streams, rivers, reservoirs, estuaries, lakes, seas or oceans.

fresh water sea water brackish water

Ground water - underground shallow and deep aquifers from which groundwater can be extracted by construction of a water well (dug or drilled), and spring water fed by underground streams emerging in rocks.

Rain water - captured in cisterns, buckets and rain barrels, and creating ephemeral streams, ponds and puddles.

Glacial water - water melt from ice fields, such as the Himalayan mountains of Nepal

Man-made lakes, wastewater holding ponds, and lagoons.

Water Quality Properties

Salinity pH - acidity and alkalinity of water; neutral pH is 7.0. Hardness Turbidity Colour Taste and Odour Contaminants - chemical, microbiological, biological, physical

The water quality properties are largely dependent on the type of source water and the presence of polluting sources that introduce contaminants into the water source.

What are examples of water quality properties of the five different types of water sources?

More discussion on what quality properties as it influences drinking water treatment and waste water treatment is provided in the course on Technical Solutions.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M020C001WQPollution.htm[11/3/2014 5:19:41 PM] WLC Template

Point Sources and Non-Point Sources of Pollution (Chemical Biological and Physical)

Point Sources are fixed stationary sources of pollution. Non-Point Sources are diffuse and non-stationary sources of pollution.

Point Sources of Pollution

Direct discharges via wastewater end-of pipe outfalls of industrial wastewaters and municipal wastewaters are common point sources of pollutants released to surface waters.

Smoke stacks from industrial facilities, incinerators, and chimneys are common point sources of pollutants released to the air.

Pollutant point sources should be constructed to contain, treat and remove contaminants in order to limit and control their release into the environment, especially those that are priority pollutants and pathogens of concern, as designated under international health and environmental codes of conduct and trade agreements, for the protection of human health and the environment. These include

Persistent organic pollutants (POPs) that accumulate in the water column, in sediments, and in fish and other aquatic species, especially in top predatory fish and fish-eating birds and mammals, and are a potential threat to human health and endangered species.

Known and emerging human and animal pathogens (bacteria, viruses protozoa) and parasites,

Contaminants present in emissions in toxic quantities

Nutrients (nitrogen, phosphorous, potassium, and carbon containing compounds and ions)

Dissolved organics and totals suspended solids to minimize wastewaters from causing high Biological Oxygen Demand (BODs) in the receiving waters

And removal of solids to prevent sedimentation problems in receiving waters.

Non-Point Sources of Pollution

Contaminants in soils can move off the land into surface waters; Contaminants can be deposited from the air into nearby and distant surface waters, especially under high velocity wind conditions, And contaminants can seep and infiltrate through soils and the overburden into the groundwater

Pathogens can be introduced into the water by run off originating on feedlots and surface water flowing over pastures or fields where animal wastes and human excreta and decomposing carcasses and garbage are present.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M020C002PtandNPtSources.htm[11/3/2014 5:19:41 PM] WLC Template

Image: sources of contaminants in the environment Source:

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M020C002PtandNPtSources.htm[11/3/2014 5:19:41 PM] WLC Template

Image: Figure of point-sources and non-point sources of pollution. Source: Dubrovsky et al., 2010 Cited in Harter et al., 2012

References:

Harter, T., J. R. Lund, J. Darby, G. E. Fogg, R. Howitt, K. K. Jessoe, G. S. Pettygrove, J. F. Quinn, J. H. Viers, D. B. Boyle, H. E. Canada, N. DeLaMora, K. N. Dzurella, A. Fryjoff-Hung, A. D. Hollander, K. L. Honeycutt, M. W. Jenkins, V. B. Jensen, A. M. King, G. Kourakos, D. Liptzin, E. M. Lopez, M. M. Mayzelle, A. McNally, J. Medellin-Azuara, and T. S. Rosenstock. 2012. Addressing Nitrate in California's Drinking Water with a Focus on Tulare Lake Basin and Salinas Valley Groundwater. Report for the State Water Resources Control Board Report to the Legislature. Center for Watershed Sciences, University of California, Davis. 78 p. http://groundwaternitrate.ucdavis.edu.

World Health Organisation (WHO). 2011. Guidelines for drinking-water quality - 4th ed. 1.Potable water - standards. 2.Water - standards. 3.Water quality - standards. 4.Guidelines. I.World Health Organization. ISBN 978 92 4 154815 1

WHO, 2002. Guidelines for Drinking- Water Quality, 2nd Edition. WHO, Geneva. pp. 1-142.

WHO, 2004. Guidelines for Drinking- Water Quality, 3rd Edition. WHO, Geneva.

WHO. 2012. Water Safety Planning for Small Community Water Supplies. World Health Organization, Geneva, Switzerland. pp. 55.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M020C002PtandNPtSources.htm[11/3/2014 5:19:41 PM] WLC Template

Impacts of Pollution Sources on the Environment and Human Health Contamination of a water body by persistent substances (chemical, biological and physical) has a profound impact on both the quantity and quality of water in that area, and to surrounding areas connecting and adjacent to this body of water. Waterborne pathogens released into surface waters arising from livestock production (animal wastes), wildlife excreta, and from improperly treated human faeces and other excreta, and food wastes can have a profound influence on the quality of water. Cumulative impacts by contamination from both point sources and nonpoint sources can have profound adverse environmental consequences both upon the environment and human health by,

The spread of disease. Loss of potable sources of water supplies. Destruction of aerable land. Destruction of critical habitats for fish, and safe sources of water for livestock, game and other wildlife.

The interconnected sources of water pollution make the development and the implementation of effective remediation programs often complex. For the prevention of contamination of source waters and for their clean-up, control of pollution should be at the source. Pollution controls, water treatment and remediation action plans for water systems should be based on the principles of risk assessment, by utilizing

a multi-barrier approach, and multi-disciplinary and an integrated water resources and health management approach.

Water quality testing, monitoring and surveillance can provide important information on the quality and quantity of the water body and water system, especially about the safety the water body for drinking water and potable uses, and of its acceptability for other specified uses.

Testing of important water quality indicators of safety for human health, agricultural uses, including livestock and crops, and impacts on fisheries and plants and animals should be conducted.

Monitoring and surveillance should be conducted of water quality testing results, pollutant releases inventories by polluting sources, water usage rates, and of health records and vital statistics.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M020C003ImpactsPollution.htm[11/3/2014 5:19:41 PM] WLC Template

Environmental Contaminants

Environmental contaminants are:

Biological Chemical, and Physical.

Contaminants are potentially harmful to humans animals and plants and to the integrity and vitality of populations and the ecosystems and the ecosystem services on which all life depends. Contaminants are released into the environment from human activities, by seasonal and naturally occuring processes, and severe weather and catastrophic events (i.e., natural disasters). Contaminants alter the composition, in terms of the types and amounts of chemical, biological and physical constituents and properties of air, water, soil and land, and food, making it unsuitable and potentially harmful.

Reference: World Health Organisation (WHO). 2011. Guidelines for drinking-water quality - 4th ed. 1.Potable water - standards. 2.Water - standards. 3.Water quality - standards. 4.Guidelines. I.World Health Organization. ISBN 978 92 4 154815 1 (on CD)

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M020C004TypesContaminants.htm[11/3/2014 5:19:41 PM] WLC Template

Major Contaminants Influencing Water Quality, Quantity, and Use Biological Contaminants The main types of biological contaminants influencing water quality, quantity and its use are the following,

Microbiological - pathogenic bacteria, viruses, fungi, and protozoa. Parasites - parasitic worms, trypanosomes (malaria). Infectious Disease Carrying and Venomous Pests - invertebrates (e.g., mosquitoes, flies and fleas, poisonous spiders); vertebrates (venomous poisonous snakes and rodents, bats, and other animals)

Algal blooms - cyanobacteria and dinoflagellates and their toxins. Noxious and nuisance aquatic weeds.

Reference: The World Health Organization (WHO) Drinking Water Guidelines (WHO, 2011. Guidelines for Drinking Water Quality, 4th Edition, World Health Organization, Geneva).

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M020C005BiologicalContaminants.htm[11/3/2014 5:19:41 PM] WLC Template

Types of Environmental Contaminants Chemical Contaminants Chemical Contaminants are broadly catgorized as

Inorganics - ionic forms and nonionic compounds that do not contain any carbon and hydrogen bonds.

Organics - ionic forms and nonionic compounds that contain carbon and hydrogen bonds

Inorganic and organic chemicals can be further grouped according to their physical-chemical properties, toxic action, and uses, such as those listed below.

Nutrients - chemical compounds, including minerals, vitamins and nonionic organic compounds.

Acids and alkalis Salts Heavy Metals Halogens and Other Oxidants Volatile Organic Compounds Alkylating Agents Detergents and Surfactants Persistent Organic Pollutants (POPs) Pharmaceutical and Personal Care Products (PPCPs)

Chemical contaminants that have been responsible for large-scale health effects through drinking water exposure (WHO, 2011) include the following,

Arsenic Fluoride Lead Nitrate Selenium, and Uranium

Reference:

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M020C006ChemicalContaminants.htm[11/3/2014 5:19:42 PM] WLC Template

Major Contaminants Influencing Water Quality, Quantity, and Use Physical Contaminants Examples of physical contaminants include the following,

Particulates, Sediments and Solids Coarse particulates = Total Suspended Particulate (TSP) are particles > 10 micrometers.

Fine Particulates = Particulate Matter (PM) of PM10 to PM2.5, particles sizes less than 10 micrometers.

Ultrafine Particulates ( and nanoparticles) = particles less than 2.5 micrometers

Dumping of wastes - including waste containers

Temperature

Radiation and Radioactive Materials Ionising radiation - x-rays Non-ionising radiation: EMFs, ELFs, UV

examples of radioactive materials: cesium, plutonium, 32P, 3H.

Light

Noise and vibration, currents and turbulence, including ultrasonic and sonic waves

Reference:

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M020C007PhysicalContaminants.htm[11/3/2014 5:19:42 PM] WLC Template

Microbiological Quality of Drinking Water

"Diseases related to contamination of drinking-water constitute a major burden on human health. Interventions to improve the quality of drinking-water provide significant benefits to health." (WHO, 2011)

"The potential health consequences of microbial contamination are such that its control must always be of paramount importance and must never be compromised." (WHO, 2011)

1. Microbial contaminants in drinking water supplies continue to be the primary concern in both developing and developed countries.

2. Among the greatest public health risks is the spread of infectious disease via the consumption of drinking water contaminated with faeces and other excreta from humans and animals (including birds), and via other significant exposure routes.

3. Water contaminated by human and animal faeces commonly contains pathogenic bacteria and viruses, and parasitic protozoa and worms (helminthes).

4. A pathogen is defined as an organism able to inflict damage on the host it infects. A parasite is an organism able to live on (eat) and cause damage to another organism, called the host. An infection is when an organism has colonized and is growing on (or in) the host, with or without harm to the host; an infection does not always lead to injury. Not all microorganisms are pathogens, and not all bacteria, viruses and parasites are pathogenic.

5. The microbiological quality of drinking water is based on the testing of water samples for faecal contamination, as indicated by the presence of common faecal indicator organisms.

6. The Membrane Filtration (MF) test for assessing total bacterial coliforms counts and fecal coliforms counts is a standard method used by public health laboratories.

Membrane Filtration Test

The World Health Organization (WHO) Drinking Water Guidelines

The WHO drinking water guidelines provide information on the following,

Microbial hazards and drinking-water safety, including minimum procedures and specific drinking water guideline values, and how these were derived and how they are intended to be used. Taking a systematic stepwise approach to securing microbial safety based on the preventive principles of risk management, and Implementing infectious disease prevention and control practices for ensuring the microbial safety of drinking water through a multiple-barrier approach, emphasizing the importance of source water protection.

Reference:

World Health Organisation (WHO). 2011. Guidelines for drinking-water quality - 4th ed. 1.Potable water - standards. 2.Water - standards. 3.Water quality - standards.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M020C008Microbiological%20Quality%20of%20Water.htm[11/3/2014 5:19:42 PM] WLC Template

4.Guidelines. I.World Health Organization. ISBN 978 92 4 154815 1

A PDF copy of the WHO, 2011. Guidelines for Drinking Water Quality, 4th Edition, World Health Organization, Geneva is provided in the resources folder for the Course

OECD (Organisation for Economic Cooperation and Development). 2003. Assessing Microbial Safety of Drinking Water: Improving Approaches and Methods. IWA Publishing, London, UK, pp. 1-279.

Waterborne Pathogens. 2006. AWWA Manual M 48. American Water Works Association, Denver, USA.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M020C008Microbiological%20Quality%20of%20Water.htm[11/3/2014 5:19:42 PM] WLC Template

Testing Drinking Water for Microbiological Quality

1. The microbiological quality of drinking water is based on the testing of water samples for faecal contamination, as indicated by the presence of common faecal indicator organisms.

2. The Membrane Filtration (MF) test for assessing total bacterial coliforms counts and fecal coliforms counts is a standard method used by public health laboratories.

3. 100 mL water samples, collected in sterile glass or plastic bottles, are filtered through a sterile 0.45 micron membrane filter.

4. The membrane is rinsed with sterile water and placed on the prepared Petri plate and incubated at 35°C for total coliforms and 44.5°C for fecal coliforms.

5. Coliforms are counted as the number of colony forming units (CFUs) per 100 mL water sample; Potable water should contain no CFU per 100 mL.

6. The presence of E. coli CFU indicates recent fecal contamination and is taken as an indicator of the presence of pathogens.

Membrane Filtration (MF) Test

The Membrane Filtration (MF) Test for Enumeration of Bacterial Coliforms and Fecal Coliforms, as CFUs

Drawing of bacteria in water passing through membrane filter.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M020C009Microbiological%20Testing%20of%20Water.htm[11/3/2014 5:19:42 PM] WLC Template

Bacterial colonies on filter paper Bacterial colony on agar plate

Reference:

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M020C009Microbiological%20Testing%20of%20Water.htm[11/3/2014 5:19:42 PM] WLC Template

Microbial Indicators of Water Quality 1. Indicator bacterium (IB) definition and use, including limitations 2. Estimating risk 3. Viable but non-culturable (VBNC) 4. Emerging pathogens 5. Why detect pathogens?

Challenges in the Use of An Indicator Bacterium for Faecal Contamination of Water There are challenges with the environmental sampling of water and use of an indicator bacterium for fecal pollution. These challenges include the following: 1. Variations in microbial species and distributions in nature. 2. Low microbial numbers are difficult to detect. 3. Microbes that are associated with biofilms and particles. 4. Environmental factors that may prevent accurate, reliable and representative sampling. As well as numerous pollution sources for enteric microorganisms in water (surface and ground water).

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M020C010Challenges%20Faecal%20Indicator.htm[11/3/2014 5:19:42 PM] WLC Template

International Drinking Water Standards versus Guidelines 1. There are no international mandatory drinking water standards for microorganisms. 2. The WHO Guidelines are a science-based assessment of the risks to human health from biological agents in drinking water.

Reference:

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M020C011WHO%20DWG.htm[11/3/2014 5:19:42 PM] WLC Template

Monitoring and Surveillance of Microbiological Water Quality Why Detect Pathogens in Water?

Table of Water-related diseases Source: Hunter et al., 2010.

The detection of pathogens in drinking water is necessary for the following reasons,

1. Hazard identification - defining the hazard and the nature of the harm. 2. Exposure assessment- determining the numbers and estimating the intake by humans. 3. Dose–response assessment- quantifying adverse effects arising from exposure to pathogen(s). 4. Risk characterization-estimating potential and real impacts. 5. Setting standards for pathogens and the indicator bacterium (IB). 6. Conducting baseline analyses of drinking water.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M020C012WB%20Pathogens.htm[11/3/2014 5:19:42 PM] WLC Template

7. Developing clean-up goals for contaminated water. 8. Construction of what-if scenarios such as contamination of water with animal wastes, f containing pathogens, flooding, above average rainfalls, or bioterrorism events. 9. Constructing computer models. 10. To evaluate new and existing technologies in water treatment and the methods used for detection/enumeration of microorganisms. 11. To protect human health and deal with community and individual health concerns. 12. To determine how urgent microbiological problems in water are. 13. Prevention of illness. 14. To prevent exposure pathways. 15. To understand exposure pathways for humans and (domestic and agricultural animals) such as the average ingestion of 2 l of potable water per day per person x 365 days per year. 16. Microbial and chemical contaminants are not equal in their capacity to cause health effects. 17. To determine sources of uncertainty in guidelines and testing methods. 18. To find limitations in analytical methods and correct them. 19. Estimating exposures. 20. Microbial risk assessment is complicated because the outcome can be no illness to death, because of pathogen-host interactions that are variable. Host factors such as age, pre-existing immunity, nutritional status, the ability to mount an immune response, and differences in infecting strains complicate the assessment. For example, elderly people, people with chronic illness and people with medical conditions that impair their immune system are at a higher risk when challenged with pathogens. 21. Emergence factors such as land use and a breakdown of public infrastructure can create an outbreak of one or more pathogens in drinking water. 22. Increases in the number of antibiotic resistant microorganism can be considered an emergent problem. 23. Bulk processing of foods (using water) and subsequent distribution is an emergence factor with our current worldwide processing and distribution of foods. 24. Genetic mechanisms (transduction, transformation and conjugation) that promote gene transfer in microbes is an emergence factor if the transferred genes are for toxin production and antibiotic resistance(s), and the resistances are carried on transferable plasmids, or plasmids that are mobilized. 25. Global change and climate change (such as warming of waters) may allow pathogens to move into water locations where they were previously not found. 26. Other emergence factors include inadequate vaccination programs, excessive rainfall and flooding which moves animal waste into water supplies, mild winters that do not reduce microbial numbers (lower pathogen kill), lack of proper training and personnel, lack of public education, non- compliance with standards and unknown disease reservoirs from which contamination of water file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M020C012WB%20Pathogens.htm[11/3/2014 5:19:42 PM] WLC Template

supplies and recreational water can occur.

Infant mortality plot - Source: Hunter et al., 2010.

References:

Hunter, P.R., MacDonald, A.M., and Carter, R.C. 2010. Water Supply and Health. PLOS Medicine. 7 (11): 1-9 e1000361 www.plosmedicine.org

Mara, D. and N. Horan (Eds.) 2003. Handbook of Water and Wastewater Microbiology. Academic Press, NY.

Pan American Health Organization (PAHO). December 2011 Health Indicators: Building Blocks for Health Situation Analysis. Epidemiological Bulletin 22 (4):1-16

Waterborne Pathogens. 2006. AWWA Manual M 48. American Water Works Association, Denver, USA.

World Health Organisation (WHO). 2004. Using climate to predict infectious disease outbreaks: a review. Communicable Disease Surveillance and Response Protection of the Human Environent Roll Back Malaria Geneva. 2004.

WHO. 2004. Expert Consensus Expert Meeting Group in the World Health Organization (WHO). Waterborne Zoonoses:

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M020C012WB%20Pathogens.htm[11/3/2014 5:19:42 PM] WLC Template

Identification, Causes and Control. Edited by J.A. Cotruvo, A. Dufour, G. Rees, J. Bartram, R. Carr, D.O. Cliver, G.F. Craun, R. Fayer, and V.P.J. Gannon. Published by IWA Publishing, London, UK. ISBN: 1 84339 058 2.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M020C012WB%20Pathogens.htm[11/3/2014 5:19:42 PM] WLC Template

Monitoring and Surveillance of Water Quality 1. Potable water quality is safe for drinking, and is for protection of human health, individual and the public. 2. There are numerous interacting factors that will influence water quality. 3. Pollution of water is not always visible to the naked eye including, chemical microbiological and some physical contaminants. Most pathogenic organisms are microscopic and require the correct methodology to detect and enumerate them in water. Disease potential exists when host pathogen and environmental conditions interact

Venn diagram Host-Pathogen-Environmental Conditions, and Disease

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M020C014MandS%20WQ.htm[11/3/2014 5:19:43 PM] WLC Template

Microbial Source Tracking (MST) 1. Using microorganisms to determine source(s) of fecal contamination 2. MST is tool to be used in combination with other investigative processes 3. Effective in small, defined watersheds 4. Large-scale projects more difficult

MST Library Sources

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M020C015MST.htm[11/3/2014 5:19:43 PM] WLC Template

Cholera as an example of a waterborne disease

Vibrio cholera is a Gram-negative rod-shaped pathogen. V. cholera causes infections resulting in watery diarrhea and vomiting. Severe dehydration of the host can lead to death. Death can occur in 1 to 5 days. V. cholera can survive in the environment for extended periods of time.

Vibrio cholera cells

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M020C016Vcholera.htm[11/3/2014 5:19:43 PM] WLC Template

Enterohemorrhagic (EHEC) Escherichia coli (O157:H7 and others) in water Enterohemorrhagic (EHEC) Escherichia coli O1H7:57 - identification Disease description Occurrence in water Survival in water Transmission

Electron micrograph of E.coli

Escherichia coli cells viewed microscopically.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M020C017Ecoli.htm[11/3/2014 5:19:43 PM] WLC Template

Enteric viruses Viruses are various submicroscopic pathogens consisting of core single nucleic acids surrounded by a protein coat and capable of replicating inside a living cell (AWWA M35, 2006). Enteric viral infections cause gastroenteritis and/or diarrhea.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M020C018EV.htm[11/3/2014 5:19:43 PM] WLC Template

Cyanobacteria (commonly called blue-green algae) There are several cyanobacteria for example, Oscillatoria, Anabaena, Aphanizomenon and Phormidium that cause taste and odor problems in water, making it unfit for consumption. Harmful algal blooms (HAB) occur when there is an excessive accumulation of algae often in shallow, warm and slow moving water.

What are cyanobacteria, formerly called blue-green algae?

These are primitive microscopic organisms with chorophyll that live in fresh water. Their scientific name is cyanobacteria, but they are commonly known as pond scum.

Normally cyanobacteria (blue-green algae) are barely visible in surface waters, but during warm weather populations can rapidly increase to form a large mass called an algal bloom.

What conditions favour cyanobacterial growth?

Cyanobacteria (blue-green algae) thrive in areas where the water is shallow, slow moving, and warm, but they may also be present below the surface in deeper, cooler water.

One key factor affecting growth rates is the level of available nutrients, in particular phosphorus and nitrogen.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M020C019CB.htm[11/3/2014 5:19:44 PM] WLC Template

Cryptosporidium: Waterborne Pathogen Cryptosporidium parvum and Cryptosporidium hominis are obligate enteric protozoan parasites, which infect the gastrointestinal (GI) tract of animals and humans, causing cryptosporidiosis. C. parvum is a potential threat to drinking water due to the robust and indigenous nature of oocysts, resistance to conventional chlorine-based disinfection Transmitted by the fecal-oral route. Hardy oocysts. Two genotypes known. Both infect humans. One of them was renamed Cryptosporidium hominis in December 2002. Early reliable detection is needed for routine monitoring and prevention of cryptosporidiosis outbreaks.

Electron micrograph of C. parvum oocyst.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M020C020CS.htm[11/3/2014 5:19:44 PM] WLC Template

EXPOSURE - Exposure Assessment and Transfer of Disease Overview

Exposure Routes Exposure Pathways - direct and indirect Transmission of Infectious Disease Duration of Exposures - short-term; repeated short-term and long-term Similarities and differences of children and adults

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M030C001Exposureoverview.htm[11/3/2014 5:19:44 PM] WLC Template

Water is Essential for Life

Water has a profound influence on human health. A minimum amount of drinking water is required daily for survival. Water plays an important role in the control of disease through: personal hygiene and cleaning washing away dirt, wastes, pathogenic and toxic contaminants improved sanitation

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M030C002WExposure.htm[11/3/2014 5:19:44 PM] WLC Template

Zoonoses Zoonoses are diseases and infections transmitted from animals to humans and vice versa caused by bacteria, viruses, parasites or unconventional hosts.

Waterborne Zoonoses

Waterborne zoonoses involve water as a breeding place and growth medium increasing the opportunity for environmental exposures and disease transmission to hosts.

Vector-borne Disease (and indirect exposure pathway to pathogens and parasites)

Water influences the transmission of vector-borne disease (VBD) by providing essential habitat for certain life-stages of insects and other pests which are carriers of agents of zoonotic infectious diseases.

Important determinants in vector-borne disease transmission include:

1. Vector survival and reproduction

2. The vector’s biting rate, and

3. The pathogen’s incubation rate within the vector organism

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M030C004Zoonotics%20and%20VBD.htm[11/3/2014 5:19:44 PM] WLC Template

Waterborne disease interactions in the water environment. copied from WHO Section 1 Expert Consensus Expert Meeting Group in the World Health Organization (WHO). Waterborne Zoonoses: Identification, Causes and Control. Edited by J.A. Cotruvo, A. Dufour, G. Rees, J. Bartram, R. Carr, D.O. Cliver, G.F. Craun, R. Fayer, and V.P.J. Gannon. Published by IWA Publishing, London, UK. ISBN: 1 84339 058 2.

Environmental Exposure Factors - Geographical Location and Climate, Temperature, Precipitation

Vectors, pathogens and hosts must each live, survive and reproduce within the same range of geographical locations, including artificial climate controlled facilities, with optimal climatic conditions.

Temperature and precipitation are important climatic factors, also sea-level elevation, wind, and daylight duration are important factors influencing vector and pathogen survival and transmission of vector-borne diseases.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M030C004Zoonotics%20and%20VBD.htm[11/3/2014 5:19:44 PM] WLC Template

Transmission Routes of Infectious Diseases and Pathways of Exposure to Toxics

Direct Exposures and Transmission of Disease Agent

Ingestion Inhalation Person to person contact Contact exposure - skin contact, contact with intact and abraded (broken) skin Injection - invasive exposure by contaminated and used needle puncture, accidental puncture injection by contaminated sharp objects and edges e.g. broken glass, nail and metal (rusty), human and animal bite and scratches.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M030C005DirectExposure%20routes%20and%20pathways.htm[11/3/2014 5:19:44 PM] WLC Template

Transmission Routes of Infectious Diseases and Pathways of Exposure to Toxics

Direct Exposures and Transmission of Disease Agent

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M030C005DirectExposure.htm[11/3/2014 5:19:44 PM] WLC Template

Exposure Pathways to Environmental Contaminants Indirect Exposures to Chemical Contaminants and Pathogens and Parasites

Eating contaminated fish and shellfish is a common route of transmission of waterborne pathogens and parasites, particularly by eating raw and insufficiently cooked fish and shellfish.

Eating contaminated fish and shellfish is a common exposure pathway to inorganic and organic chemical contaminants, particularly mercury, arsenic, cadmium and other heavy metals, POPs, bacterial and algal toxins, and radioactive compounds accumulated in the flesh, fat and oils, and organs.

Person to person contact with pathogens in excreta - faeces, urine, blood, and vomit and the transfer of pathogens and parasites into foodstuffs, beverages, other products.

Maternal transfer: The transfer from mother to infant of some forms of toxic metals and organic compounds and of pathogens and parasites.

Contaminated and adulterated food, including vegetable, fruits, grains and meat.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M030C006IndirectExposure%20routes%20and%20pathways.htm[11/3/2014 5:19:45 PM] WLC Template

Exposure Pathways to Environmental Contaminants Indirect Exposures to Chemical Contaminants and Pathogens and Parasites

Eating contaminated fish and shellfish is a common route of transmission of waterborne pathogens and parasites, particularly by eating raw and insufficiently cooked fish and shellfish.

Person to person contact with pathogens in excreta - faeces, urine, blood, and vomit and the transfer of pathogens and parasites into foodstuffs, beverages, other products.

Maternal transfer: The transfer from mother to infant of some forms of toxic metals and organic compounds and of pathogens and parasites.

Contaminated and adulterated food, including vegetable, fruits, grains and meat.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M030C006IndirectExposure.htm[11/3/2014 5:19:45 PM] WLC Template

Principle Elements of Faecal-Oral Disease Transmission

Faecal-oral disease transmission

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M030C007faecaloraltransmission.htm[11/3/2014 5:19:45 PM] WLC Template

Biological and Chemical Contaminants and Water-Related Disease Interactions in the Environment

Exposure Pathways to Contaminants in Water

SOURCES OF WATER-RELATED CONTAMINANTS IN FOOD 1. Pollution of the Aquatic Environment: a. Sanitation – municipal effluents to water from humans and animals b. Industrial, Manufacturing, Commercial – effluents to water c. Energy and Electricity Generation d. Agricultural e. Air Deposition (wet and dry) of Industrial Emissions f. Particulates in Windblown Dust and Soils g. Debris, urine and faeces, pathogens, toxins, nutrients from living and decaying wild animals plants, microorganisms (bacteria, algae, viruses, protozoa, parasitic worms, fungi, TSEs), and leaching of toxic substances from geological materials.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M030C008watercontaminantsexposurepathways.htm[11/3/2014 5:19:45 PM] WLC Template

2. Water Usage: a. Irrigation, Animal Watering b. Fisheries Habitat c. Food Processing

3. Food Handling and Food Service: a. Cleaning b. Preparation c. Cooking d. Storage, Packaging, and Refrigeration e. Re-heating

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M030C008watercontaminantsexposurepathways.htm[11/3/2014 5:19:45 PM] WLC Template

Exposure Pathways for Zoonoses (transmission of infections of humans and animals) The occurrence of waterborne zoonotic diseases depends on several factors.

Mapping Poverty and Zoonoses Hotspots Source: Map by ILRI, published in an ILRI report to DFID: Mapping of Poverty and Likely Zoonoses Hotspots, 2012.

Exposure Transmission of Zoonoses

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M030C009Zoonoses%20exposure%20pathways.htm[11/3/2014 5:19:45 PM] WLC Template

Elements of transmission of zoonotic diseases. Source CDC

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M030C009Zoonoses%20exposure%20pathways.htm[11/3/2014 5:19:45 PM] WLC Template

Types of Exposure:

Type of Exposure to a contaminant Duration of Exposure (Exposure period) (biological and chemical)

Short-term: usually less than 24 hours. Also refers to high Acute intensity short-term exposure

Long-term: recurring exposures lasting more than three months, and a substantial part of a lifetime. Repeating events in a Chronic lifetime. Example, exposures that occur by daily consumption of drinking water. Exposures to common foods frequently eaten.

Intermediate-term: lasting more than 24 hours, several days but Sub-Acute less than one month; infrequent repeated events. Also refers to less severe effects than acute effects.

Lasting between one to three months; recurring exposures Sub-Chronic more often than sub-acute exposures but not daily. Could involve recurring frequency for several months back to back.

Factors Influencing Exposures (and Effects)

The type of substance - biological (type of) , chemical (type of), physical (type of) Exposure and transmission route Administered Dose Duration of exposure and the incubation period Life-stage and gender of the exposed The health and nutritional status of the exposed The internal dose at the target site Secondary exposures Co-exposure to multiple substances The prevailing climatic conditions and seasonal and environmental aspects and cultural and behavioural practices.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M030C010InfluencingFactorsExposure.htm[11/3/2014 5:19:45 PM] WLC Template

EXPOSURE - CHILDREN AND ADULTS

On a kilogram per body weight basis (pound for pound basis) infants and children often received higher environmental exposures to contaminants than adults if exposed to the same amount of contaminants in air, water and soil and other media.

The breathing zone of toddlers and young children is different and is closer to the ground in comparison to adults, especially infants and toddlers on the ground and crawling.

Children consume more food per body weight than do adults while consuming fewer types of foods, i.e., have a more limited diet.

Children engage in crawling and mouthing (i.e., putting hands and objects in the mouth) behaviors, which can increase their exposures.

Children often spend more time outdoors than adults. Children including adolescents often have more contact with the soil and ground in their surrounding environment and may engage in hand to mouth activity especially infants and young children as they explore their environment and during the day.

Children may have direct contact with plants and animals and surface waters sand and sediments (beaches, lakes, streams, waterholes and puddles and ponds) during play and work activities.

Children and youth may be less inhibited and engage more in risk taking activities involving contact with various environmental contaminants in polluted waters and areas.

Infants and young children are more susceptible to life-threatening outcomes of dehydration and inadequate nutrition, and are at greater risk of mortality and severe and chronic morbidity from acute diahhroeal disease and water related exposures to pathogens and parasites, and harmful exposures to chemical and physical contaminants in drinking water and contaminated water used for washing bathing and food preparation.

For more information refer to other parts of this course dealing with epidemiology and risk assessment of children and other susceptible and vulnerable populations (e.g., Modules 04 and 06).

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M030C011childrenexposure.htm[11/3/2014 5:19:46 PM] WLC Template

ENVIRONMENTAL FATE and TRANSPORT

The behaviour and movement of substances in the environment occurs within four major environmental compartments.

Interactions between four major environmental compartments - air, water, soil, and biota.

PHYSICAL-CHEMICAL PROPERTIES OF CHEMICALS GOVERNING ENVIRONMENTAL FATE IN WATER and THE AQUATIC ENVIRONMENT

i) Water solubility ii) Volatility iii) Vapour pressure iv) Fat solubility – lipophilicity v) Octanol-water partition coefficient -Kow vi) Adsorption vii) Complexation

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M030C014Environfate.htm[11/3/2014 5:19:46 PM] WLC Template

Health Effects Assessment and Health Outcomes TOXICOLOGY: An Introduction to Basic Principles and Concepts What is Toxicology? Toxicology is the study of the science of poisons to predict their harmful health effects in living organisms, including:

humans animals and birds fish and other aquatic species invertebrates plants microorganisms and ecosystems.

Toxicology has developed from the science of ancient poisoners and therapeutic medicine. Toxicology is the study of the toxic or harmful effect(s) of chemicals and the effective dose or concentration in biological systems at the molecular, cellular, tissue, organ and whole organism level. Toxic substances may be: i) Naturally occurring, and ii) Anthropogenic (formed by man-made processes)

Toxic substances include:

Nutrients Inorganic chemicals Organic chemicals Drugs (natural and synthetic) Biological agents Physical agents

Toxic levels are often >>> Natural levels in healthy living organisms Toxicity occurs at concentrations of contaminant that are greater than physiological levels in healthy living organisms.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M040C001toxicology.htm[11/3/2014 5:19:46 PM] WLC Template

Health Outcomes Waterborne Disease

Waterborne disease occurs worldwide in both epidemic and endemic forms, in both developed and less developed countries.

Diarrhoeal disease and water-related faecal-oral pathogens affect billions of people worldwide and is a major public health concern.

About four billion cases of diarrhoea occur each year, leading to millions of deaths, much of it caused by waterborne zoonotic pathogens; intestinal worms infect more than a billion people worldwide.

About 90% of diarrhoeal diseases in children occur in those under five years of age, contributing to upwards of 3,000,000 deaths in children per year in the developing world.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M040C001WBD.htm[11/3/2014 5:19:46 PM] WLC Template

Toxicology Toxicology integrates information on the following components obtained through observation and data gathering with thoughtful processes

1. Exposure (as a function of dose and time) - external measurements and estimations (i.e., intakeof air, water, soil and contaminant concentrations in environmental media) 2. Observed and Measured Effects - acute and chronic effects; includes internal measurements and estimations of absorption, distribution, metabolism and excretion (elimination) 3. Mode of Toxic Action and Mechanism of Toxic Action - process of adverse effects involving target tissues and organs, point of contact and systemic distribution, reversible and cumulative tissue concentration and damage, threshold fof effects versus self-propagating non-threshold, toxic parent chemical and metabolic activation.

Why Study Toxicology? To determine the: i) Cause-and-Effect Relationship of chemical(s) exposure(s) and specific toxic effect(s). ii) Type and Severity of Toxic Effect of chemical(s) exposure in a certain organism. iii) Toxic Dose - how much chemical is a poison. iv) Safe Dose - “Theoretical” – how much chemical is safe. NOTE: Cannot prove a negative (no effect). The exact dose that causes no effect cannot be precisely measured. v) Mode of Toxic Action and Mechanism of Toxic Action – how a chemical causes harm vi) To predict and estimate whether or not exposure to a chemical/substance will cause a harmful effect.

Toxicology involves the application of knowledge and methodologies of:

Biology Chemistry Mathematics and Physics.

In addition to experimental in vivo studies in laboratory animals, modern toxicology includes the study of molecular biology and in vitro systems (non-animal studies) using toxic chemicals as tools to discover biological, molecular, and genetic processes, modes of toxic action and mechanisms of toxic action.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M040C002toxicology2.htm[11/3/2014 5:19:46 PM] WLC Template

The Basic Underlying Principle of Toxicology is:

“The Dose Makes the Poison”

in other words, “All substances are poisons; there is none which is not a poison.” Paracelsus 1493-1541 (Physician- Alchemist)

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M040C003toxicologybasicprinciple.htm[11/3/2014 5:19:46 PM] WLC Template

THE TOXICOLOGICAL PRINCIPLE OF DOSE

DOSE = Amount of toxic agent (chemical, biological, physical) received by the organism The toxic agent is the substance(s) capable of exerting a harmful biological response. The Biological Response is a function of the Dose received at the Target Site of Toxicity. For example. An external dose would be that administered as an oral dose, inhaled dose, or through skin contact. An internal dose would be that taken-up by the body into the bloodstream and distributed to target tissues and target organs. A localized dose may occurr by external contact with epidermis (skin contact) that does not penetrate tissues and does not reach the blood.

DOSE Dose is expressed on a body weight basis (µg/kg body weight)

TOXICITY Any substance (naturally occurring and derived from human activities and processes) can be toxic provided the dose is great enough. Including nutrients and vitamins (e.g. vitamin A, B,C, D and E), minerals (e.g., sodium, calcium, iron, magnesium, and trace minerals), amino acids and proteins (e.g., meat, fish, eggs, seeds and nuts), fats and carbohydrates (cholesterol, animal and plants fats, sugars, starches) and other constituents in foods and the environment.

The Comparative Toxic Potency Compounds can be ranked quantitatively according to their toxicity by a comparison of the dose causing the same toxic effect, and by the same exposure route and in the same test organism. For example, these four compounds are compared on the basis of their lethal dose. The lower the lethal dose the more toxic (harmful) the compound.

Compound A: lethal toxic dose = 1 mg/kg;

Compound B: lethal toxic dose = 1000 mg/kg;

Compound C: lethal toxic dose = 25 mg/kg;

Compound D: lethal toxic dose = 150 mg/kg.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M040C004doseconcept.htm[11/3/2014 5:19:46 PM] WLC Template

Question: List the above four compounds in the order of their toxic potency from the most toxic to the least toxic. Answer: Most toxic is A > C > D > B is least toxic.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M040C004doseconcept.htm[11/3/2014 5:19:46 PM] WLC Template

EXPOSURE Contact with chemical, biological and physical substance. Major Factors of Exposure:

the route of exposure the concentration of contaminant (e.g., concentration in drinking water) the amount of exposure (e.g., amount of drinking water ingested, area of contact with skin and lungs)

duration of exposure period (i.e., time) and chronicity of exposure (i.e., number of contact events within a specified period)

exposure pathways

Exposure Pathways Pathways of contact between organism and chemical, biological and physical substance in environemntal media food and consumer products. Exposure Routes: ingestion; inhalation; and dermal. Other routes: injection (intradermal, intramuscular, subcutaneous, interperitoneal, intravenous). Four Categories of Exposure (on the basis of duration and frequency of contact):

Acute exposure short-term exposure (single exposure) Subacute exposure short-term exposure (several days) Subchronic exposure long-term exposure (weeks to months) Chronic exposure long-term exposure (months to years) and life-time exposure

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M040C005exposuretoxicityconcept.htm[11/3/2014 5:19:46 PM] WLC Template

DOSE RESPONSE RELATIONSHIP

The dose response curve is the plot of the Dose (ug chemical/kg body weight) versus the Biologic Response (i.e., toxic effect that is being studied)

The dose response curve provides information about the amount of chemical exposure and the corresponding biological response (i.e., toxic effect).

The examples of dose response curves show a) dose vs response; b) dose response curve showing threshold for no effects; c) shallow dose response curve; and d) steep dose response curve

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M040C006doseresponsecurves.htm[11/3/2014 5:19:47 PM] WLC Template

REPEATED EXPOSURES (DOSING)

Change in blood concentration of chemicals with different rates of elimination

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M040C007repeateddosingelimination.htm[11/3/2014 5:19:47 PM] WLC Template

TOXICITY ASSESSMENT Toxicity endpoints includes a wide range of different harmful effects such as the following,

Death Impaired Growth Developmental and Reproductive Effects Birth Defects Neurotoxicity (damaged to nervous system) Cancer Immunotoxicity (damage to immune system) Other effects

Important Considerations in Toxicity Assessment 1. The nature of the biological response. 2. The degree of the biological response. 3. The severity of the biological response. 4. Biological significance - physiological range on average, corresponding to age, sex, life- stage, metabolism

Four Major Considerations in the Biological Significance of the Response (Klassen and Eaton, 1991) 1. Timing of response related to exposure. Examples:

Cancer Neurotoxicity Delayed Lethality (death) Impaired reproduction and reduced fertility

2. Location of the harmful effect.

Localized effects Systemic effects

3. Reversibility of effects.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M040C008toxicityassessment.htm[11/3/2014 5:19:47 PM] WLC Template

Reversible effects Irreversible effects

4. Consistency or reproducibility of effects (in multiple studies in humans and in the same animal species and in several different biological species)

Inconsistency in reproducibility of effects Increased/decreased sensitivities

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M040C008toxicityassessment.htm[11/3/2014 5:19:47 PM] WLC Template

Mode and Mechanism of Toxic Action How chemicals and other substances cause harmful effects. Factors affecting toxic response include the following,

1. The rate of toxic injury and the type of interaction

2. The biological importance of the processes affected.

3. The ability of affected tissues to function while damaged.

4. The ability to repair or replace damage tissue with regenerated tissue.

General Modes of Toxic Action and Specific Mechanisms of Toxic Action

Interference with normal receptor-ligand interactions

- neuroreceptors and neurotransmitters

- hormone receptors

- changes in enzyme activity (P450; CYP1A)

- transport proteins

Interference with membrane functions and structure - cell lysis, narcosis; liver toxicity

Interference with cellular energy production; oxygen transport; cyanosis Binding to biomolecules - damage to proteins; interference with protein synthesis; renal (kidney) toxicity

Perturbation of calcium homeostasis Toxicity from selective cell loss

Cancer and Carcinogenicity - Non-lethal genetic alterations in somatic cells Carcinogenic chemicals have been divided into the following two classes (Williams and Weisburger, 1991) 1. Genotoxic Carcinogens – “Classic” carcinogens that chemically interact with DNA and cause DNA adduct formation. No threshold for effects. 2. Non-Genotoxic Carcinogens – substances do not interact with genetic material; an alternative biological effect is the basis of carcinogenicity. Threshold for effects exists.

Birth Defects

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M040C009MMOA.htm[11/3/2014 5:19:47 PM] WLC Template

Toxicity of Chemical Mixtures Chemical interactions are:

Additive Antagonistic Synergistic Potentiative Non-interactive

Examples of chemical interactions include the interactions of therapeutic drugs, the interactions of narcotics, interactions of metals, and the relationship of poisons and antidotes

Assessing Toxicological Effects of Environmental Mixtures (low level exposures) General Underlying Assumptions 1. Assume additivity of exposures to environmental mixtures of potentially toxic contaminants for those acting on same target tissues causing similar effects (e.g., lung cancer, liver cancer) 2. Assume additivity of exposures to environmental mixtures for potentially toxic contaminants acting by the same modes and mechanism of toxic action. 3. Assume for environmental mixtures of contaminants acting by different mechanisms of toxic action their interactions may be non-additive.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M040C010Mixtures.htm[11/3/2014 5:19:47 PM] WLC Template

TOXICITY TESTING ENDPOINTS Acute Tests

EC50 and ED50: Effective Concentration causing toxicity or observed effect in 50% of study population (organisms tested) and Effective Dose in 50% of study population (organisms tested)

LC50 and LD50: Lethal Concentration causing death in 50% of study population (organisms tested) and Lethal Dose causing death in 50% of study population (organisms tested) .

Chronic Tests LOEC and LOEL: Lowest-Observed-Effect-Concentration and Lowest-Observed-Effect- Level LOAEC and LOAEL: Lowest-Observed-Adverse-Effect-Concentration and Lowest- Observed-Adverse-Effect-Level MATC: Maximum Acceptable Toxicant (toxic substance) Concentration NOEC and NOEL: No-Observed-Effect-Concentration and No-Observed-Effect-Level NOAEC and NOAEL: No-Observed-Adverse-Effect-Concentration and No-Observed- Adverse-Effect-Level

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M040C011EC50LC50.htm[11/3/2014 5:19:47 PM] WLC Template

Exposure (Intake into Body) - Absorption, Distribution, Metabolism, Excretion (ADME) Uptake of chemical contaminant into blood and tissues is generally followed by conversion into less toxic metabolites and toxic metabolites and elimination from body via excretion in urine, faeces, breath, sweat, hair and nails, or retained in tissues.

Exposure Intake - The process involving exposure to a contaminant in air, water, soil-dust, food, consumer product (i.e., in external media) via inhalation, ingestion, skin contact, and an estimation of the amount of exposure. Absorption - The process involving the uptake of contaminant into blood and tissues in the body (e.g., uptake of contaminant across skin and membranes of tissues of the alimentary tract and respiratory tract, nervous and circulatory system). Distribution (Systemic Exposure) - The translocation of contaminant via blood and lymph throughout body to target tissues distal to portal of entry Metabolism - The biological conversion of parent chemical into other compounds called metabolites. Excretion (Elimination) - The removal processes and estimation of the amount of parent chemical and metabolites eliminated from the blood and body tissues. Accumulation - The potential exists for a gradual increase in tissue concentrations of a contaminant when the rate of uptake and rate of intake and metabolism exceeds the rate of elimination of parent chemical and its metabolites Cumulative and Lifetime Exposures Re-Release Incubation period for pathogens

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M040C012ADME.htm[11/3/2014 5:19:47 PM] WLC Template

FACTORS INFLUENCING EXPOSURE AND POTENTIAL FOR TOXICITY AND HEALTH OUTCOMES

A. Environmental (Non-Biological) Factors Influencing Potential for Harmful Effects from Water- Related Contaminants Water Quality Factors · Salinity · pH · Water hardness · Organic carbon (dissolved or particulate) · Methylation · Light intensity · Temperature · Dissolved oxygen · Mixtures · Sediment characteristics · Exposure pathway (e.g. water, dietary, sediment)

Physical-Chemical Properties

· Water solubility of compound; log Kow; Volatility; HL constant; Koc

Exposure Conditions: · Short-term · Continuous long-term · Mixtures

B. Host and Receptor Factors (Biological Factors) Influencing Susceptibility and Vulnerability Characteristics of the exposed receptor (individual) or organism; includes individual, population, community, ecological processes. Variations in physiological and biological characteristics

· Life stage and development · Reproduction · Gender

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M040C013environfactors.htm[11/3/2014 5:19:48 PM] WLC Template

· Genetics · Nutritional status · Health status · Other stress

Biological Considerations in Toxicology · Differences in species sensitivity · Respiration and metabolic rate · Gender and reproduction · Genetics · Growth and development · Nutritional Status · Lifestyle and behaviors (exposure pathways) - also referred to as social and cultural factors influencing exposure · Food consumption and types of foods - also referred to as social and cultural factors influencing exposure

Note: All of the above are dependent on the life stage.

Acclimation and Immunity to Previous Exposures

Physiological change to environmental stress such as change in temperature, salinity, and pH, and in environmental concentrations of chemicals and other substances. Immunological protection from disease through vaccination against vaccine preventable disease and through previous exposure and illness to the same pathogen(s).

Behaviour and Living and Working Conditions and Habitat

Behaviour, lifestyle and living and working conditions affect interactions and contact with various environmental media as well as to environmental contaminants in those environmental media (air, water, soil and dust, food, other).

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M040C013environfactors.htm[11/3/2014 5:19:48 PM] WLC Template

SUSCEPTIBLE AND VULNERABLE POPULATIONS

Women and Children Early-Life Stages Pregnant women and developing fetus Adult - Reproductive-ages Adult elderly Genetics - metabolism Health status

Immunization Immune - passive vs. active Nutritional status Sensitization from previous exposures

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M040C014sensitivepopulations.htm[11/3/2014 5:19:48 PM] WLC Template

ASSESSING HEALTH OUTCOMES - EPIDEMIOLOGY PRINCIPLES METHODS AND APPLICATIONS Overview and Objectives 1. To understand common terminology and procedures used in epidemiology for data collection, analyses, reporting, and surveillance of water-related impacts on health. 2. To describe basic epidemiological principles and methods. 3. To gain an appreciation of the importance of standardized procedures for data collection analyses reporting monitoring and surveillance, as applied in epidemiology and public health studies. 4. To increase core knowledge of epidemiological principles methods and applications necessary for understanding interpreting and communicating the findings of health assessments and outcome studies.

Building A Conceptual Framework For Epidemiological Investigations

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C001Epidemiology%20overview.htm[11/3/2014 5:19:48 PM] WLC Template

Epidemiological Monitoring and Surveillance

A two-step process Step 1. Data Collection Step 2. Data Analysis

Monitoring and surveillance involves a systematic study of an event, activity or outcome, in terms of its

occurrence frequency and distribution.

Traditional historical epidemiology involved the study of epidemics of infectious disease. Current modern epidemiology involves a systems approach to studying health outcomes.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C002EpiMandS.htm[11/3/2014 5:19:48 PM] WLC Template

Integrated Water and Health Monitoring & Surveillance Systems Should track and report on indicators for all three elements:

1. Water Quantity

2. Water Quality

3. Health Impacts and Outcomes

Enabling awareness of the consequences of local and regional water-related impacts on health protection and disease prevention. An assessment should be carried out involving a comparison of monitoring data to standards for water quality and analyses and observation of patterns and trends in water quality indicators,

1. over a specified period of time (days, weeks, months, years).

2. for differences in locations.

3. for differences in sources of water supply and treatment processes.

Often overlooked are existing and sometimes competing water demands to support:

flora and fauna physical needs of the whole ecosystem – plants, trees, wildlife natural water cycle - evaporation, precipitation, surface and groundwater recharge by infiltration and runoff

natural decomposition and mineralization of organic materials and incorporation into soils and sediments

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C003IntegratedWHM&S.htm[11/3/2014 5:19:48 PM] WLC Template

Integrated Water and Health Monitoring & Surveillance Systems Should track and report on indicators for all three elements:

1. Water Quantity

2. Water Quality

3. Health Impacts and Outcomes

1. over a specified period of time (days, weeks, months, years).

2. for differences in locations.

3. for differences in sources of water supply and treatment processes.

Often overlooked are existing and sometimes competing water demands to support:

flora and fauna physical needs of the whole ecosystem – plants, trees, wildlife natural water cycle - evaporation, precipitation, surface and groundwater recharge by infiltration and runoff

natural decomposition and mineralization of organic materials and incorporation into soils and sediments

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C003IntegratedWHMandS.htm[11/3/2014 5:19:48 PM] WLC Template

Why is it Important for Monitoring and Surveillance Systems for Health and Water Quality and Water Supply to be Integrated?

To provide assurance of the safety of the drinking water supply and its sustainability for the vitality and development of the community, including for safe hygiene and sanitation use and for local food production and healthcare.

To provide assurance of the quality and sustainability of the water supply for use in agriculture, the food and beverage industry, manufacturing, and other industries.

To assess and maintain a sufficient and adequate water supply available, in terms of both quality and quantity, to meet the needs of the local community for drinking water, personal hygiene, and sanitation, and other water uses.

To assess health outcomes as it relates to the above three bullets.

What is involved? Surveillance of data for trends and patterns and reporting, as appropriate to the exposure period of concern for the contaminant, including the incubation and latency period for illness. Identify coincident impacts and potential indicators in terms of time place duration and type of impacts with those from monitoring and surveillance data for the drinking water quality and water supply.

To ensure that the results are accurate, reliable and representative of the water supply and the environmental conditions and data are comparable to drinking water guidelines and suitable for proper disease surveillance standardized methods must be followed.

Health Impacts and Outcomes - Water Borne Diseases, Acute and Chronic Illnesses Identification and tracking the number of cases of infectious disease and acute and chronic illnesses, corresponding to specified periods matching the surveillance period to short-term and acute exposure periods and longer term subchronic and chronic exposures, as appropriate. Surveillance of clinics and hospital emergency admissions and discharges. The identification, tracking and follow up of cases of disease, and the analyses and reporting of the findings are beneficial for responding to disease outbreak in a community and may involve the following,

Search for new cases and follow up of existing cases (treatment, recovery, transmission)

Determination of an outbreak Differentiating between an epidemic and endemic situation Probable sources of exposure to contaminants in water supplies, aerosols, food, fecal material, inadequate sanitation and hygiene, sewage and waste water file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C004why%20integrated.htm[11/3/2014 5:19:49 PM] WLC Template

discharges. Probable exposure routes (ingestion, inhalation, contact with skin, mucous membranes, bloodstream)

Spread of infectious and communicable disease and acute illness (e.g., acute diarrhoea and gastrointestinal illness)

Prevention of the sale and distribution of unsafe contaminated water and food with in a community, state, province, country, and across borders through trade (e.g., sale of potable water and beverages, fresh and processed food and nutritional supplements, livestock and pets, animal feed, medicinal and therapeutic products, cosmetics and personal care products).

Water Quality Monitoring sampling and testing of drinking water for: Biological indicators of fecal material pathogens and parasites; Chemical contaminants; and Properties of taste odour turbidity pH conductivity and colour. Monitoring should be done at multiple points within the water supply and along the distribution system, including at the tap. Surveillance of water quality (drinking water, surface water, ground water) including tracking of testing results trends and patterns over daily, monthly and annual time periods. Testing results for the sampling period should be compared to standards for safe drinking water and other potable uses, as appropriate to the exposure route and duration and contaminant of concern.

short-term and acute exposures - daily testing results for levels of microbial indicators for the assessment of potential risk of waterborne disease corresponding to the length of the incubation period; testing results for harmful concentrations of chemical contaminants of concern for assessment of potential risks of acute and short-term effects

longer-term sub-chronic and chronic exposures - analyses of trends and patterns of testing results over months and years for water quality indicators contaminants of concern for chronic effects

document recurring water quality issues by type date location and duration

Environmental monitoring and surveillance of ground water quality and surface water quality. Collection and testing of water samples taken upstream, at the source, and downstream of point and non-point sources provide a snap-shot (point-in-time) indicator of water quality for contaminants.

Water Quantity

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C004why%20integrated.htm[11/3/2014 5:19:49 PM] WLC Template

Monitoring and surveillance - measurement and tracking of the usage capacity and availability of potable water supply, and of other water uses. Involves methods such as metering at point of use, and regular measuring for changes in levels of the water table and water levels of lakes and rivers.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C004why%20integrated.htm[11/3/2014 5:19:49 PM] WLC Template

Purpose & Components of an Integrated Management System for Water-Related Impacts on Health Purpose:

In the case of waterborne diseases, the primary purpose of monitoring and surveillance is to identify the primary source(s) of contaminated water supply and secondary sources, in order to break the chain of disease transmission and exposure to prevent harmful exposures and potential for disease, and acute and chronic illness.

Monitoring and surveillance provide useful information for risk management decisions pertaining to the control and prevention of and decrease in potential for harmful water-related health impacts.

The Components: 1. Monitoring and surveillance systems for water quantity, water quality and waterborne health disease, acute and chronic illness, resources, personnel and training for each. 2. Critical points of contact identified for each of the three separate monitoring and surveillance systems, including a communications alert mechanism.

3. Systematic and standardized data collection and analyses and reporting on standardized measurement criteria and performance indicators for each system (water quality, water quantity, water-borne disease) 4. Iterative feedback, especially on key performance indicators for verification of findings and communications across systems, as appropriate, especially for those key indicators for critical points of failure.

The above integrated systems at the regional, state/provincial and national and international level would cross and intersect those under the purview of · public health · public water works (municipalities), · organizations for the protection of health and the environment, · natural resources, · business development

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C005components.htm[11/3/2014 5:19:49 PM] WLC Template

WHAT IS EPIDEMIOLOGY? Definition The word Epidemiology is derived from the Greek words “epi” meaning on or upon + “demos” meaning the people + “logos” meaning the study of Epidemiology is the study of -

diseases and health impacts in exposed groups of people. the occurrence, the spread and the pattern of disease and health impacts within a population.

the change over time within a population in the occurrence, spread and pattern of disease, as the natural course of disease within a population.

the analytic investigation of the association of probable risk factors, or determinants of health (of disease) with disease and health-impacts.

changes in response to an intervention to eliminate and prevent further disease from occurring in a population.

“Epidemiology is the study of the distribution and determinants of health-related states or events in specified populations, and the application of this study to the control of health problems.”

Last, J.M. editor. Dictionary of Epidemiology. 4th Edition. New York, Oxford University Press; 2001. P.61. cited by U.S. Centre for Disease Control

Epidemiology Tools Epidemiology uses the following tools,

1. Descriptive observations to characterize and define disease case definitions and events leading up to, during and following outbreaks of disease.

2. Basic statistical methods and statistical parameters to investigate, design studies, collect, track, and analyse trends and patterns in data, track the progress of disease within a population, evaluate the outcome of interventions, and compare differences among groups of exposed and unexposed persons.

Epidemiological Studies Epidemiological studies should follow a systematic and unbiased approach in the collection, analyses and interpretation of data. Epidemiological studies, typically involve the comparison of results in valid comparison groups using biostatistics and the laws of probability. An observed value may be compared to an expected value, often using probabilities and statistical methods. Similarly, a control group without disease health effects or without intervention treatment

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C009epidefine.htm[11/3/2014 5:19:49 PM] WLC Template

and exposure may be compared to a group with a specified disease health effects and a group with intervention treatment and exposure.

Reference: U.S. Centre for Disease Control http://www.cdc.gov/ (Internet Access Required)

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C009epidefine.htm[11/3/2014 5:19:49 PM] WLC Template

What is an Epidemiologist? An “Epidemiologist” is a person who studies epidemiology and conducts epidemiological studies.

The epidemiologist measures the frequency of disease occurrence in a population.

The 5 Ws Typically, the epidemiologist aims to answer the following five questions (5 Ws): 1. What is the health impact or health-related-event? what 2. Who are affected and exposed? person 3. Where did it take place? place 4. When did it occur? time 5. Why and how? exposure pathways, modes of transmission, risk factors, causal associations

On its own epidemiology cannot prove a particular exposure caused a particular outcome, but it can provide sufficient evidence to allow and enable taking appropriate control and prevention measures.

Reference: U.S. Center for Disease Control http://www.cdc.gov/ (Internet Access Required)

Epidemiology Applications in the Study of Water-Related Impacts on the Health of the Public Evidence Building By 1. Monitoring and surveillance of the relationship of water quality on health. 2. Monitoring and surveillance of the relationship of water quantity on health. 3. Monitoring and surveillance of the relationship of interventions to the water supply on health. e.g.,

Monitoring and surveillance of waterborne diseases and water-related health impacts and outcomes associated with exposure to biological contaminants in water.

The study of outbreaks of acute illness and chronic disease associated with environmental exposures to chemical and physical contaminants in water.

Morbidity in mothers and children under 5 years of age from acute and recurring (chronic) diarrhoea and gastrointestinal illness associated with the water supply.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C012Epi5Ws.htm[11/3/2014 5:19:49 PM] WLC Template

Epidemiological Terms:

Outbreak - the occurrence of new Baseline. No Outbreak. Endemic cases. No new case(s) of disease in a previously cases. unexposed population.

Cluster - aggregated group of cases Non-cluster, when the number of separate cases believed to be present in a higher are present in low numbers below those expected number than expected, even though for a geographical area. Cases are not the expected number may not be aggregated. known.

Epidemic - spread of disease or illness from one exposed person to Endemic - the ongoing presence of disease, health an unexposed person in the condition or illness in a population within a population; usually sudden geographical area. The observed number of cases occurrence in a population above that is considered usually present within a given what is expected on average for that area. population in that geographical location.

Sporadic - a disease agent or health Pandemic - an epidemic that has spread over condition that occurs infrequently or several countries and continents, usually affecting irregularly in a population. a large number of people.

versus Prevalence -a measure of all existing cases (new and ongoing) and of the health or disease status of a population at a specific point in time. A measure Incidence - a measure of newly of both incidence rate and duration of disease, and occurring cases of disease in a reflects survival and disease. Used when population. A measure of changes in measuring the occurrence of birth defects, health state in the population. In the degenerative and chronic diseases for which a study of causation incidence is more clear time of onset of disease in not easily appropriate than prevalence determined, and have a long latency period. For long term strategic planning prevalence of disease may be more suitable measure than incidence.

Incidence Rate - the measure of occurrence of new cases of disease per unit of person-time. Excludes Prevalence Odds - ratio of diseased to non- persons who do not get disease diseased or the ratio of the proportion of the illness or health-related impact. The population that has disease to the proportion that incidence rate ranges from 0 to >1. It does not have the disease.(P/N-P). Prevalence is not a measure of the proportion of proportion is dimensionless and ranges from 0 to

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C013EpiTerms.htm[11/3/2014 5:19:49 PM] WLC Template

a population with disease or health- 1. related event. Often written as a multiplier of 1000 (e.g., 0.01 is written 10 per 1000 person-years).

Sensitivity - the ability of a test to Specificity - the ability of a test to correctly identify correctly identify “true positives”, “true negatives”, persons without disease. The persons with disease. Sensitivity is ability to distinguish false negatives is important to important for reliably identifying all the control of the spread of disease. cases in an exposed population.

Other Epidemiological Terms Hyperendemic Epidemic proportion Time of the reference event Incident Incidence time Incidence rate Incidence proportion (survival proportion) Person attributes Person-time; total person-time at risk or population-time at risk Rate Secular (Long-term) trends Seasonality and time-scale Standardization Causation

Reference: U.S. Center for Disease Control http://www.cdc.gov/ (Internet Access Required)

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C013EpiTerms.htm[11/3/2014 5:19:49 PM] WLC Template

Epidemiologic Triad - Simple Model of Disease Causation

Rothman's Causal Pies

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C014Causation.htm[11/3/2014 5:19:49 PM] WLC Template

Disease Transmission – Chain of Infection

Chain of Infection

Concept of Herd Immunity

Vaccine Preventable Disease (VPD) Create a "resistant majority"

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C015herdimmunity.htm[11/3/2014 5:19:49 PM] WLC Template

Epidemiological Methods There Are Two Basic Methodologies of Epidemiology:

Descriptive Epidemiology Analytic Epidemiology

What is Descriptive Epidemiology? Descriptive Epidemiology covers: Time Place Person. The available raw data are compiled, may be aggregated and are carefully examined by the epidemiologist in a stepwise manner:

What is Analytic Epidemiology? Analytic epidemiology involves the comparison of at least two groups; a control group or reference population and an exposed group or population at risk, for a specified time period. For example, in an study of exposure history of cases of disease in the exposed group are compared to those in an appropriate reference population or control group. Analytic epidemiology involves i) the investigation of cause and effects. ii) identifying and quantifying the association (relationship) between exposures and health outcomes

iii) testing hypotheses about causal relationships.

Reference: U.S. Center for Disease Control http://www.cdc.gov/ (Internet Access Required)

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C016EpiMethods.htm[11/3/2014 5:19:50 PM] WLC Template

Descriptive Epidemiology - Methods

Step 1: Become familiar with the data. Determines the comprehensiveness and completeness of available records. Step 2: Determine the extent and pattern of the health problem being investigated. Step 3: Give a clear, straight-forward communication of a detailed description of the health-related status of a population. Step 4: Determine if there are areas or groups in the population that have high numbers of disease within the observation period of data collection and as a proportion (i.e., rates of disease).

The findings from descriptive investigations can provide clues to possible causes that can be further investigated by formulating testable hypotheses.

The actual testing of those hypotheses is the focus of analytic epidemiology.

Reference: U.S. Center for Disease Control http://www.cdc.gov/

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C018EpiDescriptive.htm[11/3/2014 5:19:50 PM] WLC Template

Analytic Epidemiology Studies are Either Observational or Experimental Studies. Involving the testing of hypothesis in a comparative analysis.

Observational Epidemiological Studies Experimental Epidemiological Studies

1. Cohort Study –

A cohort study involves assigning participants to Clinical trial –individuals exposed either an exposed study group or to a non exposed group and then tracking study Community trial –community exposures participants for the development of disease. Participants are not intentionally exposed, but are Community intervention study observed for exposure over a specified period of

time. The unexposed group serves as the baseline or reference population and provides the The investigator determines the exposure expected amount of disease in the community or conditions for the study subjects. Involves population. controlled exposures treatments or Follow-up or Prospective Cohort study. interventions. There are two groups for comparison – a control unexposed, no Retrospective Cohort Study. treatment or no intervention group and an exposed treatment or intervention group.

2. Case-Control Study -

Groups of people or case-patients each with a case of disease are enrolled and assigned to a case- group. A comparison control group is also created by enrolling people without disease. Previous exposures for each of the groups are compared. The control group is used to define the baseline or expected amount of disease exposure in that population.

3. Cross-sectional study -

Measures exposure and disease simultaneously by taking a sample of persons from a study population and assessing the status of existing disease in the population at that specific point in time, without regard to the duration. Provides an estimate of the presence of disease (prevalence) in a population. A cross-sectional study is the weakest type of observational study; commonly used in descriptive epidemiology; cannot distinguish causality

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C020EpiAnalytic.htm[11/3/2014 5:19:50 PM] WLC Template

(determinants for survival from disease).

Reference: U.S. Center for Disease Control http://www.cdc.gov/ (Internet Access Required)

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C020EpiAnalytic.htm[11/3/2014 5:19:50 PM] WLC Template

DISTINGUISHING BETWEEN EPIDEMIOLOGIC STUDY DESIGNS

Source: Allan Smith 2011. Overview of epidemiological study designs. A presentation to the Fogarty Workshop, Bodhgaya Bihar, November 2011.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C022EpiStudy%20Designs.htm[11/3/2014 5:19:50 PM] WLC Template

Distinguishing Between Different Epidemiological Study Designs

CASE SERIES: Follow of patients only with rare and unusual conditions. Only a few individuals; relies on inference about some unusual characteristic. ECOLOGIC STUDIES: No individual link between exposure and outcome

CROSS-SECTIONAL STUDIES: Identify exposure and disease in a population at the same time.

CASE-CONTROL STUDIES: Start by identifying cases with the disease.

COHORT STUDIES: Start by identifying an “exposed” population group before disease occurs.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C023Study%20Designs.htm[11/3/2014 5:19:50 PM] WLC Template

Distinguishing Between Different Epidemiological Study Designs

CROSS-SECTIONAL STUDIES: Identify exposure and disease in a population at the same time.

CASE-CONTROL STUDIES: Start by identifying cases with the disease.

COHORT STUDIES: Start by identifying an “exposed” population group before disease occurs.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C023Study%20Designs2.htm[11/3/2014 5:19:50 PM] WLC Template

3C Epi Study Types (source: Allan Smith 2013)

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C024Epi3CStudyTypes.htm[11/3/2014 5:19:50 PM] WLC Template

Disease Timeline

Disease timeline from susceptibility through exposure, onset and recovery disability death

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C028DiseaseTimeline.htm[11/3/2014 5:19:51 PM] WLC Template

Exposure Period of an Outbreak

The exposure period is the period of time before the clinical symptoms of disease occur. The median, mode of date of onset of disease and the minimum and average incubation period are used to pinpoint the exposure period of an outbreak.

Reference: U.S. Center for Disease Control http://www.cdc.gov/ (Internet Access Required)

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C030Exposureperiod.htm[11/3/2014 5:19:51 PM] WLC Template

Four Common Patterns of Epidemic Curves

Four types of epicurves a) common point source, b) common persistent source, c) common intermittent source, and d) propagated source

EXAMPLE: Epidemic Curve Plot of Cases of Disease (Salmonella) versus Date and Time of Symptom Onset.

[Source CDC - Epidemiology page 1-37].

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C036epidemiccurve.htm[11/3/2014 5:19:51 PM] WLC Template

Salmonella Outbreak

Reference: U.S. Center for Disease Control http://www.cdc.gov/ (Internet Access Required)

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C036epidemiccurve.htm[11/3/2014 5:19:51 PM] WLC Template

Hypothesis Testing for Statistical Significance The most basic measure of risk of development of disease is probability, expressed as a "p-value". Epidemiologists Are Often Asked What is the chance that a particular exposure in a population, behavior or hereditary trait (i.e. attribute or risk factor) would cause or contribute to the development of disease? How reliable are the data and how representative are the data of the population "true" risk? What is the probability that the relative risk ratio (RR) 1.0 could have occurred by chance alone? Defining the Level of Significance In other words, is the finding of a relative risk ratio different than 1.0 statistically significant at the specified level of certainty, given the available information? Before carrying out the statistical analysis, the epidemiologist must specify the level of significance, indicated by defining the amount of variation in the observations that would be acceptable. Interpreting the Findings It is possible that the calculated "p-value" may be a chance finding rather than a true explanation of an outbreak. Results of a study that has insufficient statistical power could arise by chance alone. For example the findings of a study that consists of a small number of observations (n<30).

When interpreting the findings of the data analysis one must ask the following,

Is statistical significance the same as biological and health significance? How confident can one be in accepting the null hypothesis? What is the statistical power of the analysis? Are there biological and other plausible explanations beyond statistical findings that are equally or more compelling that would strengthen the argument for accepting or rejecting the null hypothesis in a weight of evidence approach?

A note of caution: In an epidemiological investigation of impacts on health outcomes, one should consider the consequences of making and error in a decision about accepting or rejecting the null hypothesis. You may be right or wrong. An exposure is or is not causally related to disease.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C037statistical%20significance.htm[11/3/2014 5:19:51 PM] WLC Template

Chi-Square Test - Test of Statistical Significance A Chi-square test is a statistical test of significance to determine the probability of finding an association as large or larger on the basis of chance alone. The most common statistical test for determination of the probability ("p-value") for data in a two-by-two standard table is a chi-square test. It is possible that the calculated "p-value" may be a chance finding rather than a true explanation of an outbreak which happens when a study has insufficient statistical power, such as when a study consists of a small number of observations (n<30). For smaller studies, n <30, the Fisher Exact Test is often a more reliable statistical test to use than the chi-square test.

Note of caution: In a public health epidemiological investigation one should consider the consequences of making and error in a decision about accepting or rejecting the null hypothesis. You may be right or wrong.

An exposure is or is not causally related to disease.

Step 1 Develop the Hypothesis for Testing

Example,

The Null Hypothesis states the exposure (or risk factor of interest) is not related to disease; thus, the expected RR = 1.0.

Step 2: Develop the Alternative Hypothesis (states the opposite is true)

The Alternative Hypothesis states the exposure (or risk factor of interest) is associated with disease; thus, the expected 1.0 > RR >1.0

If the null hypothesis is shown to be statistically implausible or false then it is rejected in favour of the alternative hypothesis.

Step 3. Create a Two-By-Two Table

This is discussed in detail elsewhere in the course.

Step 4. Calculate the Chi-Square Statistic

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C040chisquaretest.htm[11/3/2014 5:19:51 PM] WLC Template

Box Chi Square Statistic

Before calculating the chi-square statistic, one must specify the requirement for the level of statistical significance in order to "accept" or "reject" the Null hypothesis. (i.e., what is the cutoff for statistical significance?)

A level of significance of 5% or 0.05 , indicates a 95% percent statistical degree of confidence in the findings.

Using Chi-Square Tables, from the corresponding "p-value" for the probability estimate it can be determined whether the specified level of statistical significance is equal, greater than, or lesser than.

A Chi-square value larger than 3.841 would correspond to a p-value smaller than a probability (level of significance) of 0.05 (5%).

Meaning if the calculated chi-square value is >3.841 then the null hypothesis at the 5% level of significance can be rejected.

Example

Chi-Square p- Statistic value

persons drinking from 37.20 calculated water container vs. those from Two-By-Two <0.001 not RR = 5.8 Table

Null hypothesis RR = 1.0 3.841 0.05

Alternative hypothesis RR >3.841 <0.05 >1.0

Conclusion - Reject the null hypothesis and accept

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C040chisquaretest.htm[11/3/2014 5:19:51 PM] WLC Template

the alternative hypothesis that the RR of 5.8 is statistically significant (p- value <0.001)

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C040chisquaretest.htm[11/3/2014 5:19:51 PM] WLC Template

Confidence Intervals Epidemiological studies commonly report the 95% confidence interval (95% C.I.). The 95% C.I. corresponds to the cutoff level of statistical significance of 5% (p-value= 0.05). The 95% C.I. indicates the variance in the data and the lack of precision in the strength of the association (RR) between the exposure and the risk of disease.

A wider confidence interval indicates greater variance in the data and a lack of precision. A narrow confidence interval indicates less variance in the data and more precision.

The underlying assumption is repeated sampling of a normal probability distribution of the population (assumed to be normal).

Normal distribution curve

The 68 · 95· 99.7 rule for Normally Distributed Data For normally distributed data:

68% of the data falls within ± 1 standard deviation of the mean; 95% of the data falls in the range from –1.96 standard deviations to +1.96 standard deviations (within two standard deviations of the mean);

and 99.7% of the data falls within approximately 3 standard deviations of the mean.

The 95% C.I. does NOT mean that the probability is 95% that the “true” risk in the population falls within the interval specified.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C042Confidenceintervals.htm[11/3/2014 5:19:51 PM] WLC Template

The 95% C.I. does mean that given a large enough sampling effort that on average, we are 95% confident that the “true” risk in the population lies within the specified interval.

Calculating a 95% Confidence Interval for a Mean Calculate the mean and its standard error. Then multiply the standard error by 1.96. The lower limit of the 95% confidence interval = mean minus 1.96 x standard error. The upper limit of the 95% confidence interval = mean plus 1.96 x standard error.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C042Confidenceintervals.htm[11/3/2014 5:19:51 PM] WLC Template

Sensitivity

Standard Notation "True Positive" and "True Negative"

Example: Cholera from Drinking Water in Container, sensitivity and specificity.

The above example shows the calculation, using a standard notation, of the two-by-two table. The sensitivity and specificity of drinking water in container as a source of disease in party guests, respectively was calculated to be 91.8% and 61%. The results suggest that the probability of false negative, a Type II error, is low (<10%) and the probability of false positives, a Type I error, is moderate (~40%). The statistical power of the test (1-β) is high with a positive predictive power of 70.9% and the negative predictive power is 87.8%. The likelihood ratio of positives is 91.8/39 = 2.4 and the likelihood ratio of negatives is 8.2/61 = 0.13, indicating that drinking contaminated water from the container is positively associated with developing disease and that the findings of a negative association between not drinking the water and not developing disease by chance alone are low.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C045Standardnotationsensspec.htm[11/3/2014 5:19:52 PM] WLC Template

Simple Random Sampling (SRS), Distribution of the Data and Statistics Simple Random Sampling (SRS)

Data are collected following a simple random sampling method, called an SRS frame or grid. The method gives every possible collection of n observations (or units of sample) the same chance of being chosen.

It is done in a fair and unbiased manner and the data that are collected are fair and unbiased. It is NOT a convenience sample. A convenience sample is typically biased.

A Parameter versus A Statistic

A parameter is a numerical characteristic of a population

A statistic is a numerical characteristic of the sample. Do not know the "true" value of a population parameter, but the numeric value of a "statistic" is known from the sample and changes with each sample.

Variability

Is the difference in the value of the statistic between samples of the same size (n).

Representativeness

The sample statistic for an SRS should be representative of the broader population.

Sampling Distribution

A predictable pattern of values in repeated sampling is called the sampling distribution.

Types of Error (Bias and Precision)

The sampling distribution of a statistic tells about the bias and precision of the sampling.

The objective of a good sampling program is to have both low bias and high precision; meaning the sampling results are repeatable and representative of the true population parameter “p”.

The precision of the sample statistic to estimate the “true” population parameter increases as the size of the sample increases, but does not depend on the size of the population, as long as the population is much larger than the sample.

A large sample size increases precision regardless of the size of the population and can be increased to as high as desired by taking a large enough sample.

Assessing the Distribution of the Data In large population studies consisting of many repeat sampling the distribution of the data should be assessed to determine the appropriateness of different statistical tests. Normal Distribution - the curve is symmetrical in shape on both sides of the peak, also called a "bell curve" with both tails extending to infinity. The peak represents the mean, median, and the mode, all are the same. The area under the normal curve determines the spread of the data defined by the standard deviation and confidence interval. Skewed Distribution - have more extreme values at the ends of the distribution and are asymmetrical, skewed or non-normally distributed; the mean, median, and mode are not the same.

Central Tendency of the Data - most commonly defined by the mean, median and the mode; the central tendency is also called the measure of central location in epidemiology studies.

Spread of the Data - commonly described by the interquartile range, variance and the standard deviation. A box and whiskers plot provides visual representation of the data. Median and Mean - The mean is affected by extreme values, whereas the median and the mode are not. Geometric Mean - is used when log transformation of the data are used to give a more symmetrical curve (normal curve) rather than the unadjusted observations. Midrange - is the halfway point or mid-point in the dataset of observations

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C048SRSStats.htm[11/3/2014 5:19:52 PM] WLC Template

Bell Shaped Curve Three Identical Curves with Different Central Locations Three Distributions with the Same Central Location but Different Spreads

Three Distributions with Different Skewness

Six Figures are Sourced from CDC's Principles of Epidemiology on Public Health Practice. a) Bell curve, b) identical curves with different central location, c) same central location but different spreads, d) normal curve with 1, 2, and 3 std dev, e)three distributions with different skewness, f) box and whisker plot

Recommended Measures of Central Location and Spread by Type of Data (CDC)

Type of Distribution Measure of Central Location Measure of Spread

Normal Arithmetic mean Standard deviation

Asymmetrical or skewed Median Range or interquartile range

Exponential or logarithmic Geometric mean Geometric standard deviation

Reference: U.S. Center for Disease Control www.CDC.gov (Internet Access Required)

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C048SRSStats.htm[11/3/2014 5:19:52 PM] WLC Template

Representing Data

Box Two By Two Table (Effect; No Effect)

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C052representingdata.htm[11/3/2014 5:19:52 PM] WLC Template

Representing The Data Examples of FOREST PLOTS

Urinary % MMA and RR of Arsenic associated disease

30 Most Common Specific Causes of Death; RR for Current Smoker versus Never Smoker

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C053representingdata2.htm[11/3/2014 5:19:52 PM] WLC Template

Source: Copied from the UK Women’s Tobacco Smoking Study (Pirie et al. 2012), The 21st Century hazards of smoking and benefits of stopping: a prospective studypective study of 0ne million women in the UK. www.thelancet.com (Internet Access Required) Published Online

October 27, 2012 http://dx.doi.org/10.1016/S0140-6736(12)61720-6 (Internet Access Required) See Online/Comment http://dx.doi.org/10.1016/S0140-6736(12)61780-

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C053representingdata2.htm[11/3/2014 5:19:52 PM] WLC Template

Example of Calculation of the Relative Risk (RR) - A Retrospective Cohort Study

Scenario: An outbreak of acute gastrointestinal illness has occurred in persons who had attended a family wedding, and a retrospective cohort study is conducted to follow up on the outbreak.

1. Each person is questioned about possible sources of exposure and their activities.

2. The drinking water in the container is a strong suspect source of outbreak.

3. The epidemiologist constructs a line listing for all persons attending the wedding, and calculates an attack rate for the persons who were ill that drank from the drinking water container (Population A). The epidemiologist also calculates an attack rate for those who had signs and symptoms of illness, but who did not drink from the same container of drinking water (Population B).

4. Using standard notation a two-by-two table is prepared showing the data for the presumptive causal exposure item (drinking water from the container).

i) the RR is calculated

The relative risk (RR) is the ratio of the Attack rate (AR) in the exposed population (A) to the Attack rate in the non-exposed population (B).

RR = ARPopA / ARPopB

A:B RR A:B RR = 1.0 A:B RR >1.0 <1.0

suggests that there is suggests that no discernible or the risk of measurable difference suggests that the specific exposure in population disease between the risk of A was associated with an elevated risk of disease (attack rate) disease (attack rates) (attack rate) when compared to that in population is less in the in the two populations B. population A (A,B) compared (e.g. vs. population exposed vs. non- B exposed).

ii) and, the population attributable risk is calculated.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C060ExampleRRRetrocohortstudy.htm[11/3/2014 5:19:53 PM] WLC Template

Population Attributable Risk Percent

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C060ExampleRRRetrocohortstudy.htm[11/3/2014 5:19:53 PM] WLC Template

Case-Control Studies and the Calculation of the Odds Ratio (OR) In a case-control study the population must be well defined and is followed for a specified time period. The same questions are asked to members of both the disease symptomatic group (or exposed group) of cases and the control group without disease.

Selection of the Control Group Members of the control group must not have the disease, but should be representative of the population in which the cases of disease occurred. The underlying assumption is that all members of study (cases and controls) are similar in all other aspects, except the disease exposure being evaluated. Choosing the appropriate control is difficult, and influences the study outcomes.

Calculation of the ODDS Ratio (OR) The epidemiologist constructs a two-by-two table and calculates an Odds Ratio (OR). The Odds Ratio = (number of exposed cases x number of unexposed controls) ÷ (number of exposed controls x number of unexposed cases) = ad/bc

Hypothesis Testing - Chi-square Test for Statistical Significance The null hypothesis in a case-control study is the OR = 1.0. A chi-square test determines if the p-value for the study is < 0.05, the selected level of significance. The smaller the p-value, the more improbable that the null hypothesis is true. The 95% confidence interval is calculated. A wide confidence interval indicates large variability in the data; if the 95% C.I contains 1.0, the probability could be that the exposures of the case and control groups are not significantly different.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C062CaseControlOR.htm[11/3/2014 5:19:53 PM] WLC Template

Monitoring & Surveillance How can demographics and population health statistics be used in monitoring and surveillance?

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C070ManSuses.htm[11/3/2014 5:19:53 PM] WLC Template

Monitoring & Surveillance What are the uncetainties and the sources of uncertainties? What are the strengths and limitations of meta-data? It important to ask questions and take into account uncertainties when conducting and interpreting the public health implications of studies of pooled data analyses using meta-data.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C072MandSuncertainties.htm[11/3/2014 5:19:53 PM] WLC Template

Monitoring and Surveillance - Demographics, Population Ecology and Susceptible Populations

Baseline knowledge on the status of past and current conditions in the community, corresponding to the locale situation and the time period. Relevant, adequate and reliable sources are critical to monitoring and surveillance of water- related health impacts.

Monitoring and surveillance data are used in

needs assessments situational assessments environmental scans risk assessment outbreak investigations risk reduction strategies and risk management options and risk communications, as appropriate to the situation and the community, including adopting, adapting and creating as necessary for those most susceptible and vulnerable.

These data are useful for providing evidence underpinning important public health messages,

pertinent to developing, implementing, and advocating for general and targeted risk management strategies for the prevention of harmful water-related impacts on health.

particularly, those affecting susceptible and vulnerable populations.

For example, strategies aimed at decreasing infant, child and maternal mortality and morbidity attributed to health impacts involving availability and accessibility of the water supply (quality, quantity and distribution) and water sanitation and hygiene issues.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C073demographicpopstatsvulpop.htm[11/3/2014 5:19:53 PM] WLC Template

Monitoring & Surveillance - National Statistics

In developed countries, publically reported national health statistics on health outcomes provide information on the health of the population, lifestyle and environmental factors. These typically include,

· general health

· disability

· diseases and health conditions

· environmental factors

· health care services

· life expectancy and deaths

· life style and social conditions

· mental health and well-being

· pregnancy and births

· and prevention and detection of disease.

The U.S. CDC has an extensive listing of topics important to public health in the United States, particularly to that of susceptible and vulnerable populations of newborns, children, women, seniors, persons with pre-existing health conditions, and other populations.

For example, CDC also maintains statistics on congenital abnormalities, teen pregnancy, leading causes of death, infertility, divorce, nursing home care, Alzheimer’s disease, asthma, births method of delivery, multiple births, osteoporosis, physical activity, health care records, emergency department visits, home health care, mental health and other important topics to public health. Statistical data on geographical area of residence, race and heritage is also collected by CDC.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C074MandSNational%20statistics.htm[11/3/2014 5:19:53 PM] WLC Template

National Voluntary Surveys Repeated national surveys of nation food baskets, nutrition, fitness and exercise, and other lifestyle and behavioral habits A chronological “snapshot” and the survey findings are interpreted as “population estimates” of health status. A proper simple randomized sampling (SRS) design should produce results that would be representative of the overall population.

Two examples are:

The U.S. NHANES - U.S. National Health And Nutrition Examination Survey The Canadian Health Measures Study (CHMS)

When conducting survey and analyzing data from health information and statistics databases - - - the Researcher should ask questions such as: Are the sources that gathered the data free of biases? Who paid for the study? Are the data representative to the intended purpose? What is the study design and how was the sampling done? Are the data biased? Look for consistencies or inconsistencies in the methods of data sampling and data collection and data analyses? Are they measuring the same outcome? Are the data expressed in standardized and comparable units? What are the implications of making an error?

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C075MandSNationalSurveys.htm[11/3/2014 5:19:53 PM] WLC Template

Monitoring & Surveillance Sources of Information Organization for Economic Cooperation and Development (OECD) Generates statistics on the status and performance of its member countries OECD statistics are considered to be less influenced by individual federal bias than those derived by the countries themselves. OECD.Stat includes data and metadata for OECD countries and selected non-member economies. OECD Health Status provides statistics on the health status at the country level of information aggregation on variables such as, - mortality and life expectancy by specified disease classifications and corresponding to age and gender; - mortality for the total population at birth; - causes of mortality including all causes and specific causes; - infant and maternal mortality - further classified by infant mortality, neonatal mortality, perinatal mortality, maternal mortality; - potential years of life lost from all causes and specific causes; - morbidity and perceived health status by age and gender; - infant health low birth weight; - dental health; - communicable diseases limited to AIDS, incidence of pertussis, measles, and hepatitis B; - cancer statistics for malignant neoplasms (general) and of the colon, lung, female breast, cervix and prostate. - OECD Demography and Population provides statistics on migration and population, general statistics for each country, the environment, education and training, financial, agriculture and fisheries, development and more.

Others The World Health Organization (WHO) The Centers for Disease Control (CDC) The United Nations Economic Comission for Europe And many more....

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C076M&SOECDsources.htm[11/3/2014 5:19:54 PM] WLC Template

Others The World Health Organization (WHO) The Centers for Disease Control (CDC) The United Nations Economic Comission for Europe And many more....

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C076MandSOECDsources.htm[11/3/2014 5:19:54 PM] WLC Template

An Historical Perspective on Epidemiology

1. Early Epidemiology – covers the period from 5th Century B.C. to 1830.

Hippocrates “On Airs, Waters and Places”

The Scientific Revolution occurring circa mid 1600s up to the early 1800s. The Royal Society of London (1660) and Sir Francis Bacon (1561-1626) - Bacon's applied scientific method - Scientia operativa and principles of induction and for refuting experiments by hypothesis testing.

2. Classical Epidemiology – covers the period from 1830 to 1940 The three streams of knowledge and scientific methods form the foundation of classical epidemiology as follows, 1. Medical 2. Systematic Mathematics and Demographics 3. Theoretical

These three streams converged providing definitive proof of the aetiology of infectious and contagious disease.

Including, the development of classical epidemiology methods, Snow's investigations on cholera, Koch’s Postulates of Disease and irrefutable proof of the Germ Theory of Disease by the Four Father's of Microbiology, registries, quantitative methods life tables of probability of survival.

Classical epidemiology assimilates Hippocrates teachings, the mathematics of probabilities and gathering of vital statistics, the Baconian approach to the scientific method of reasoning, and microscopic observations and Koch’s postulates.

3. Current Modern Epidemiology – covers the period from the1940s, post- World War II, up to the beginnings of the 2nd Millennium AD. A paradigm shift occurred in 1950's onwards from studying environmental exposures (food, water and air) to behavioural exposures (tobacco smoking) and occupational exposures (mining, asbestos), and new focus on toxicants and physical contaminants file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C080epihistory%20early.htm[11/3/2014 5:19:54 PM] WLC Template

(radiation). More recently, 2010, a renewal for epidemiological investigation into root causes of population health outcomes and disease development, epidemic and endemic. At the forefront is the recognition of the increased global transmission of disease and of the importance of the need for integrated management of environmental and health systems for monitoring and surveillance in the areas of population health outcomes, public health education, safety and access of water supply, fro drinking hygiene and sanitation - in home, schools, hospitals and medical clinics water quality and supply for livestock, food production, processing, and agriculture, municipal development, industry and manufacturing, and pollution releases and controls for protecting and preventing contamination of water supply (surface water and groundwater)

International Health Regulations (IHR) require by international law that that all 194 participating countries and all WHO Member Sates worldwide strengthen their national capacities for surveillance, reporting and responding to epidemic outbreaks of disease.

Some important elements and events of the era of modern epidemiology are as follows,

1. Establishment of National Registry of Births. 2. Establishment of International List of Reportable Diseases and system for monitoring and surveillance of zoonotic diseases. 3. Establishment of International Food Safety Surveillance System – International Codex Alimentarus 4. Establishment of a National Registry for Chronic diseases. 5. Establishment of National and Industry-specific Registries of Occupational Accidents, Deaths and Exposures

6. Establishment of National Registry of congenital birth defects. 7. Establishment of National Health Records System 8. Establishment of National and State Environmental Protection Legislation 9. Establishment of National Environmental Impacts and Exposure Monitoring and Surveillance Programs 10. Harmonization of National and International Pollutant Release Inventories of Priority Pollutants.

11. Over-use and non-essential use of antibiotics – therapeutic and non-therapeutic uses, including animal food production, cosmetic use.

12. Inappropriate use of disinfectants and sanitizers. 13. Uncontrolled emissions of toxic pollutants to water, air and land 14. Incomplete and inappropriate treatment of municipal and animal sewage and wastes. 15. Global trade in human body parts, animal by-products and human and animal sewage and waste.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C080epihistory%20early.htm[11/3/2014 5:19:54 PM] WLC Template

16. Increased use of immune-suppressants. 17. Global travel and emigration to remote places, including ecotourism. 18. Massive water projects, mining projects, agriculture, forestry clear cutting of rainforests, crushing of mountains, rerouting of rivers and lakes, excessive erosion and damage to riparian zones and wetlands, destruction of habitat on global scale. 19. Changes in human behaviors, lifestyles, and occupations 20. Increasing use of data registries and electronic information systems for tracking and analyses of activities, food and other products manufacturing, usage and disposal, including environmental releases and health services.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C080epihistory%20early.htm[11/3/2014 5:19:54 PM] WLC Template

Monitoring and Surveillance - Demographics and Population Statistics

A chronology from the 19th Century forward of dates, events and reports important to the development of public health systems in the U.K and worldwide, together with that of the U.K. official statistical system

1801 The first ‘Census of Population’ took place on 10 March 1801. This gave the total number of people in England and Wales as nine million.

1836 The Births and Deaths Registration Act and the Marriage Act received Royal Assent, thereby establishing secular system for recording births, marriages and deaths.

1837 – GRO (England and Wales) The General Register Office for England and Wales was established on 1 July 1837 at Somerset House. It was given responsibility for the administration of civil registration, for the analysis and publication of statistics on births and deaths, and for the conduct of the population census in England and Wales. In 1855 and 1864 the GROs for Scotland and Ireland were established, respectively.

1839 The first classification of causes of death was devised by the Registrar General

1841 The first ‘modern’ ‘Census of Population for England and Wales’ was carried out by the Registrar General – so-called because it required each householder to provide a self- completed schedule recording the names and characteristics of every individual in the household. This system has remained more or less unaltered to the present day.

1849 The first publication of the Registrar General’s ‘Quarterly Return’ which continued until 1975 when it was replaced by ‘Population Trends’.

1851 Two innovations were introduced in the processing and presentation of the Census results - the classification of people by their occupation, and geographical disaggregation.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C081UK%20chronology.htm[11/3/2014 5:19:54 PM] WLC Template

1874 - Registration The Births and Deaths Registration Act of 1874 transferred the onus of registration from the registrar to the next of kin. The Act also required the medical certification of the cause of death.

1895 The notification of infectious diseases became compulsory.

1911 The Registrar General’s ‘Social Classes’ was introduced as a means of analysing population statistics according to occupation/employment status groups. In addition, The UK adopted the ‘International Classification of Diseases’ (ICD).

1919 The Local Government Board was abolished and responsibility for statistics on health was passed to the newly created Ministry of Health.

1920 On 11 October in Paris, the League of Nations convened the International Statistical Commission.

1926 The registration of stillbirths was made compulsory.

1929 The Local Government Act of 1929 transferred the civil registration function to local authorities.

1938 The Population (Statistics) Act 1938 greatly increased the amount of statistical information obtained from those registering a birth or death.

1948 The Cancer Registration scheme was introduced.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C081UK%20chronology.htm[11/3/2014 5:19:54 PM] WLC Template

1948 The United Nations published the first issue of its ‘Statistical Yearbook’.

1949 – National Health Service Central Register The General Register Office was given responsibility for the National Health Service Central Register (NHSCR).

1952 National Registration, introduced in 1939 as a wartime security measure, was abolished in February 1952. In the meantime, the identity numbers and the registers had been used to prepare the National Health Service Central Register (NHSCR). The latter is a register of NHS patients which is kept up-to-date from returns submitted by the local registrars of births and deaths and Family Practitioner Committees (FPCs).

1960 The Population Statistics Act of 1960 required the compulsory notification of the causes of stillbirths.

1961 Sampling was introduced to the Census of Population which, for the first time, was processed on computers.

2005 The Information Centre for Health and Social Care was established as an independent body in England in April 2005 and charged with the task of collecting health statistics on behalf of the Department for Health.

http://www.statisticsauthority.gov.uk/about-the-authority/uk-statistical-system/history/statistical-system-timeline.html (Internet Access Required) (accessed on November 29, 2012).

AND 1978 Declaration of Alma-Ata stating "health, which is a state of complete physical, mental and social wellbeing, and not merely the absence of disease or infirmity, is a fundamental human right...."

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C081UK%20chronology.htm[11/3/2014 5:19:54 PM] WLC Template

Epidemiology Methods and Applications - Steps of an Outbreak Investigation

1. Prepare for field work

2. Establish the existence of an outbreak

3. Verify the diagnosis

4. Construct a working case definition

5. Find cases systematically and record information

6. Perform descriptive epidemiology

7. Develop hypotheses

8. Evaluate hypotheses epidemiologically (analytic epidemiology)

9. As necessary, reconsider, refine, and re-evaluate hypotheses

10. Compare and reconcile with laboratory and/or environmental studies

11. Implement control and prevention measures

12. Initiate or maintain surveillance

13. Communicate findings

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C082StepsOutbreak.htm[11/3/2014 5:19:54 PM] WLC Template

Epidemiology Methods - Application in An Outbreak Investigation

Step 1: Prepare and Plan for Field Work

Two Major Categories i) Scientific and Investigative Issues Research - empirical knowledge and current situation Key Contacts - knowledge and experience Gather Documentation - surveys and questionnaires, etc. Consult Laboratory - materials, methods, equipment, PPE Action Plan - senior management, objectives of field study

ii) Management and Operational Issues Select team - multi-disciplines Determine government regulatory and other NGOs involvement Develop an outbreak communications plan Establish operational and logistics plan

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C083OIStep1.htm[11/3/2014 5:19:54 PM] WLC Template

Epidemiology Methods - Application In An Outbreak Investigation Step 2: Verify the Existence of an Outbreak Determine if it is a cluster or an outbreak?

Are cases same disease? Is it a notifiable disease? Compare observed number of cases to expected number of cases?

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C084OIStep2.htm[11/3/2014 5:19:55 PM] WLC Template

Epidemiology Methods - Application In An Outbreak Investigation

Step 3: Verify the Diagnosis

Review the clinical findings and laboratory report. Visit patients with the disease. Prepare frequency distributions of the clinical features of the disease; a frequency table should be first and foremost in the investigator’s report.

Step 4: Construct a Working Case Definition

Includes simple objective clinical criteria and restrictions on the time, place, and person. All criteria must be applied consistently to all persons under investigation. Uncertainty exists in most diagnoses, especially early in the investigation – multiple categories of case definitions are often developed for: Confirmed, Probable, Possible and Suspect (Presumptive). Strategically start with a broad case definition early in an investigation. The case definition may be tightened and possible or probable definitions may be eliminated as the study progresses. For example,

1. Use a broad case definition at the start: illness among persons in a community. 2. Then conduct appropriate analyses to determine if those who drank from the well were at greater risk than those who obtained their drinking water from another source.

file:///F|/Dropbox/WaterHealthNewFinal/Course2/concepts/WH20M045C085OIStep3and4.htm[11/3/2014 5:19:55 PM] WLC Template

WATER RELATED IMPACTS ON HEALTH - PRINCIPLES METHODS AND APPLICATIONS

Overall Objectives

1. To demonstrate the relationships between water and health, especially the profound influence of water quality and quantity on human health and well being.

2. To demonstrate the importance of maintaining coordinated and integrated activities and systems for registration, monitoring, and surveillance of water quality, water usage, source waters, and water-related health problems, in order to support individual and community health and well-being.

3. To reinforce the importance of pollution prevention and protection of water supply.

Organization of the Course Materials:

The learning materials are organized into seven major sections dealing with the following subject matter,

1. Introduction

- Determinants of Health

- Background and rationale

- Problem Formulation and Scoping the Current Situation (vulnerability, susceptibility, ethics, gaps and limitations)

2. Water Quality and Quantity (Hazard Identification)

Through a health lens the focus is on water quality pertaining to the essential individual needs for drinking water and hygiene and sanitation and community use.

- Pollution Sources and Types of Contaminants

- Impact of water quality on water quantity

- Impact of water quantity on water quality

- Water Quality Testing Methods

- Water Quality Monitoring & Surveillance

3. Exposure Routes Exposure Pathways and Transmission of Infectious Disease (Exposure Assessment and Transfer of Disease)

- Microbiological - faecal-oral-route of transmission, consumption of water and food, food contact surfaces and fomites

- Chemical - short-term, repeated and long-term exposures; transferable exposures

- Similarities and differences of children and adults (Life stages approach)

4. Harmful Health Effects and Health Outcomes (Toxicological Assessment; Microbiological Assessment)

- Toxicological dose response and toxicity; exposure thresholds for harmful effects

acute effects of chemical contaminants

chronic effects of chemical contaminants

file:///F|/Dropbox/WaterHealthNew/Course2/discussion/WH20M000D001overview%20and%20organization.htm[11/1/2014 10:22:33 AM] WLC Template

sensitive populations (susceptibility and vulnerability)

- Epidemiological principles methods and applications

definition and terms; statistics; applications outbreak investigation; monitoring and surveillance

5. Social Surveys - Community - Ethics, Current Situation, Needs

- community KAP W-H social structures + norms, capital

6. Risks from Chemical and Microbiological Contaminants in Water (Risk Assessment)

- Principles of risk assessment for the determination of safe and unsafe drinking water

- Building a framework and conceptual model for assessing risks (according to the use and user)

- Characterizing risks, including uncertainty and sensitivity analysis, susceptible and vulnerable populations,

-The importance of a life-stage approach

7. Managing Risks According to Use for Health Protection and Disease Prevention (Options for Mitigation of Water- Related Health Risks)

- Risk benefit analysis; risk reduction (benefits) vs. cost; costs of doing nothing versus doing something to lower threats (risks) to health and well-being.

- Water use and user - drinking water guidelines and fish and shellfish consumption advisories

- Multi-barrier methods for disinfection, sanitation and hygiene

- Precautionary principle - protecting water quality quantity and health

- Monitoring and surveillance - water quality quantity usage and health outcomes

- Evidence - data interpretation - acting in the absence of

- Communication and education about water-related health risks and benefits change - interventions for prevention of harmful exposures

-case studies

Learning Outcomes:

Upon completion of this course unit students should be able to:

Explain the relationships between water and health, especially the profound influence of water quality and quantity on human health and well being.

Understand and explain the concept of water contamination, in particular microbiological quality of water and hazardous chemical contamination of water for drinking water use and other uses.

Understand and explain the need for maintaining coordinated and integrated activities and systems for record-keeping, monitoring, and surveillance of water quality, water usage, source waters, and water-related health problems, as it pertains to human health and community health and well-being.

Describe and identify common types of contaminants and sources of water pollution, both point-sources and non-point sources, and be familiar with WHO Drinking water Guidelines.

file:///F|/Dropbox/WaterHealthNew/Course2/discussion/WH20M000D001overview%20and%20organization.htm[11/1/2014 10:22:33 AM] WLC Template

Understand and explain the principles of exposure in terms of toxicity and pathogenicity; and describe exposure routes and exposure pathways to chemical contaminants and pathogens in environment.

Understand and explain the basic elements of transmission and prevention of water-related infectious disease, including the faecal-oral route, the cycle of waterborne zoonotic diseases, and the concept of herd immunity.

Identify and understand basic terms, principles and methods used in Toxicology, Epidemiology, Social Surveys and Risk Assessment to facilitate a basic understanding of studies of environmental health outcomes and environmental exposure studies and the implications of the findings, in terms of their robustness and limitations.

Describe the basic steps involved in risk assessment and risk management.

Understand and explain how risk assessment, risk management and risk communication, and the use of toxicological studies and epidemiological studies can be integrated into policy-making and the development of options for decision-making.

Understand the basic steps involved in an outbreak investigation, the iterative and interdisciplinary process, and the importance of following standardized and systematic methods during all stages of the investigation.

file:///F|/Dropbox/WaterHealthNew/Course2/discussion/WH20M000D001overview%20and%20organization.htm[11/1/2014 10:22:33 AM] WLC Template

Introduction

1. Water-related impacts on health and the relationships between water and health and well-being can be viewed through separate macro lenses or spheres of the following,

The User of Water - individual and community health and well being

The Needs and Usage of Water - drinking water sanitation and hygiene, food farming and agriculture, industry and commercial processing and manufacturing, other

The Quality of Water - its physical, chemical and biological properties and constituents

The Availability and Accessibility of Water (source quantity variability and distribution) - surface water groundwater rain water

2. Where overlap of these lenses occurs there is significant potential for water-related impacts on health and well being.

4. Water-related impacts on health may be beneficial or harmful and are inextricably dependent on the quality of water available for use by the user.

5. Immediate and potentially life threatening needs for health and safety and risks of acute and chronic illness and disease must be prioritized and mitigated, notwithstanding economic social and cultural aspects contributing to water-related impacts on health and well being.

This part of the course programme focuses on the relationship between water quality and exposure to contaminants in water and the prevention of water-related illness and disease.

Examples of Water Users

women, men, children (individual) and community, plants, birds and animals, fish and aquatic organisms, ecosystems; industry, manufacturer, restaurants, schools, hospitals, etc.

Examples of Water Uses

- essential water requirements to support and sustain life

- community use - potable water for drinking, sanitation and hygiene, municipal waste waters

- domestic farming and agricultural use - watering animals and gardens, irrigation of crops, raising livestock

- institutional use in community schools, healthcare clinics, hospitals, prisons

- industrial and commercial use in processing and manufacturing and associated waste waters

The Determinants of Health

The determinants of health recognized by the World Health Organization (WHO) http://www.who.int/hia/evidence/doh/en/), (Internet Access Required) include the following

the physical environments - water ( surface and groundwater - quality and quantity), air quality, land (arable, agricultural, wetlands, drylands, woodlands and rainforest, contaminated soil), geographical location and place of residence (property, municipality, region, country) and the built environment,

file:///F|/Dropbox/WaterHealthNew/Course2/discussion/WH20M001D001WRIHIntroduction.htm[11/1/2014 10:22:33 AM] WLC Template

including at work biology and genetics - infectious disease; acute and chronic illness and disease; including age and life stage personal health practices and coping skills (health status) - knowledge and behaviors, includes personal hygiene and sanitation practices gender - female and male healthy child development - essential needs are met, food and nutrition, basic hygiene, maternal and paternal care and family, infant stimulation and early child development, health services and social services social environments and support networks culture - includes language, customs, religion and beliefs socioeconomics - income and social status of individual and the community education - including schooling for children, girls and boys, young adult men and women, adults and seniors employment and working conditions - adult men, adult women, and child labour; overlaps with physical environment; includes labour laws and occupational environment, health and safety (EHS)

These determinants of health and well-being do not occur in isolation and are interactive in influencing human health and well being.

1978 WHO Declaration of Alma-Ata of the International Conference on Primary Health Care

The 1978 Declaration of Alma-Ata states "that health, which is a state of complete physical, mental and social wellbeing, and not merely the absence of disease of infirmity, is a fundamental human right...."

AND further states,

" Primary health care " 3. "includes at least: education concerning prevailing health problems and the methods of preventing and controlling them; promotion of food supply and proper nutrition; an adequate supply of safe water and basic sanitation; maternal and child health care, including family planning; immunization against the major infectious diseases; prevention and control of locally endemic diseases; appropriate treatment of common diseases and injuries; and provision of essential drugs; 4. involves, in addition to the health sector, all related sectors and aspects of national and community development, in particular agriculture, animal husbandry, food, industry, education, housing, public works, communications and other sectors; and demands the coordinated efforts of all those sectors;...... "

A copy of the WHO Europe Declaration of Alma-Ata is included in the Resources folder as a PDF document.

1986 WHO Ottawa Charter for Health Promotion

In 1986, the WHO Ottawa Charter for Health Promotion urged policy makers in all sectors to “be aware of the health consequences of their decisions and to accept their responsibilities for health” (WHO 1986).

For more information see http://www.who.int/healthpromotion/conferences/previous/ottawa/en/ (Internet Access Required)

Examples of Water Related Health Impacts

Beneficial impacts may include reduced rate of mortality and morbidity from water-related illness and disease, and economical, social and cultural improvements influencing health and well being and safety. Harmful impacts may include increased mortality and morbidity from water-related illness and disease, pollution of water resources, depletion in water resources and associated costs and liabilities for treatment and maintaining water supply, social and cultural aspects influencing health and wellbeing and safety. Physical and social impacts, including those on healthy infant and child development and maternal health.

Some populations are more susceptible and vulnerable to harmful water-related impacts on health and well being, particularly children and women, persons having dehydration and malnourishment, pre-existing health conditions (e.g., pregnancy, high blood pressure, diabetes, CVD, HIV), and the elderly, and those unaware of the importance of the health consequences of water quality for drinking water and potable use and for hygiene and sanitation

BACKGROUND AND RATIONALE FOR AN INTEGRATED APPROACH TO WATER AND HEALTH

Why An Integrated Systems Approach is Required For Water and Health file:///F|/Dropbox/WaterHealthNew/Course2/discussion/WH20M001D001WRIHIntroduction.htm[11/1/2014 10:22:33 AM] WLC Template

The pressing global problems facing society today are complex and interlinked – poverty, equity, food security, energy security, ecosystem integrity and health – and all are exacerbated by global environmental change processes, including climate change (WHO, 2004). Water is the common denominator linking and underpinning all of these issues; water is essential for all life and functions as the environmental medium through which problems can be exacerbated or mitigated. It is becoming increasingly obvious that there is no single lens or approach that can provide a sustainable solution and many examples where failure to examine a policy or problem in an integrated manner has made a situation worse, e.g. Aral Sea. Food security is directly linked to sustainable management of water resources, especially in arid and semi-arid regions. Moreover, human and animal wastes are a resource that can be used to improve agricultural yield and to create energy, provided strict rules are followed for preventing contamination of water supply and prevention of acute or chronic illness and transmissible disease. Integrated management of water resources for protection of and sustainable use of ecosystem services, are key to building resilience and mitigating impacts from natural disasters and extreme weather events. Integrated management centralized around water and sanitation is an emerging approach for community development, especially in small, rural communities. To be sustainable, access to drinking water for humans must be integrated into water management plans for livestock and crop production, and water quality management principles must applied to expand water and sanitation facilities. It further provides an opportunity for women to engage in alternative livelihoods. The incorporation of energy technologies into the water management plan improves the opportunities for sustainability.

Within the water-environment-health nexus, there are disparities between urban and rural populations, between indigenous and non-indigenous communities, and between the rich and poor. Water is flowing through landscapes and lives, connecting and impacting our livelihoods. Significant shifts in policy and practice need to occur recognizing water as not only essential, but also as a vital resource and exposure medium and a requirement by virtually all sectors, including health and wellbeing, economy, energy, food security and ecosystem services.

Globally, individual and community health and well-being are intrinsically linked to environmental integrity, water quality, water quantity and water management. Dynamic factors associated with global environmental change continue to affect outcomes. An integrated approach, encompassing biological, physical, economic, socio-political, and cultural factors is needed to address the current and future issues and challenges of water-related impacts on health and well-being (IOM, 2009).

As presented in Course 1 globally, small communities face significant challenges in managing water resources. Many are related to adequate supplies of freshwater (i.e. “water quantity”), but equally problematic is “water quality”. The term “water security” has been used to describe the status of water supply in terms of both quantity and quality. Grey and Sadoff (2007) define water security as the “reliable availability of an acceptable quantity and quality of water for health, livelihoods and production, coupled with an acceptable level of water-related risks”. This can be expanded to include the concept of safeguarding the cultural aspects of water (De Loë et al. 2007) and the maintenance of environmental services (Global Water Partnership 2000).

Water needs within human communities include both domestic (e.g., drinking, hygiene and sanitation, cooking and food preparation, laundry) and productive (e.g. agriculture, livestock, industrial processing) uses. The type of use should define the quality of the water that is required; . water for irrigation can be of lower quality than required for potable water. Moreover, secure water resources should be accessible and affordable for all community members. Inequalities in access to secure freshwater resources can lead to conflicts at international, national, regional and local scales (Jury and Vaux, 2007). Indigenous and marginalized communities are particularly at risk for inequalities related to water security (Avila, 2012)and are often ignored by the state and/or private sector during the allocation of water resources. In addition, these communities often lack the capacity to develop and sustain secure water systems, critical when a key factor for water security in this context is the level of community participation, decision-making, and ownership (MacDonald and Calow, 2009).

Secure water resources also need to be resilient to changes in the environment and human populations. Global change is already occurring in climate, land-use, urbanization, population growth and demographics, leading to e.g. economically-driven changes in diet (Vaux, 2012; IPCC, 2012; IPCC, 2007; Bower, 2002). Nearly all of the growth in the global population will occur in developing countries, many of which already have inadequate supplies of freshwater. A study of 92 developing countries by Vaux (2012) showed that, through a combination of population growth and higher incomes that drive improvements in diet, as much as an additional 5,200 cubic kilometres of land will be needed by 2050 for agriculture; thus increasing agricultural water demand. At the same time, the growth rate of large cities are confronted by increasingly greater demands for water.

While the impacts of global change on the quantity of water resources have been widely studied, there has been less work to date on the impacts of global change on water quality (Pangare and Idris, 2012). Global change will affect: a) the types and quantities of pollutants (chemicals, nutrients) and pathogens that are released; b) the transport and fate of pollutants and pathogens in the environment; c) the sensitivity of receptors (including ecosystems, livestock and humans) to these stressors. For some classes of chemicals, such as pesticides, biocides and pharmaceuticals, use will increase in response to the need for increased agricultural production, as well as the expanding number and distribution of animal and plant pests and human diseases (Boxall et al., 2009; Tirado et al., 2010; Royal Commission on Environmental Pollution, 2011). In countries with expanding economies, the use of chemicals for domestic and personal use (e.g. cleaners, detergents, disinfectants) will increase. Trends towards urbanization will file:///F|/Dropbox/WaterHealthNew/Course2/discussion/WH20M001D001WRIHIntroduction.htm[11/1/2014 10:22:33 AM] WLC Template

result in increased discharges of both domestic and industrial wastewater containing nutrients, pathogens and chemical contaminants (Evans et al., 2012). Demand for non-renewable resources will increase contamination of ground and surface water by the mining and hydrocarbon-based energy sector (oil, natural gas, coal, oil shale).

Climate induced changes in hydrological cycles and regimes will change the input, fate and transport of biological, chemical and physical contaminants in the aquatic environment, as well as the dilution potential of rivers and streams. Increases in the occurrence of extreme weather events, such as floods and droughts will alter the mobility of pollutants and pathogens (Manuel, 2006). In agricultural areas, changes in irrigation practices, such as re-use of wastewater can move contaminants from water bodies onto land (Tirado et al., 2010).

As well as affecting contaminant inputs, transport and fate, global change will also affect the structure and functioning of ecosystems. It has been estimated that 40% of humanity is already competing directly with nature for water (Safriel, 2011), and this is affecting the life-supporting capacity of ecosystems. For example, in aquatic systems, an increase in primary productivity is expected as a result of a longer growing season, increased temperature and higher nutrient inputs (Rouse et al, 1997). In response, zooplankton abundance will increase but with a decline in body size (Moore and Folt, 1993). There will be a reduction in available habitat for cool water species (LeRoy Poff et al, 2002). Climate change and nutrient releases will also affect the rates of formation and the geographical distribution of algal toxins (Marques et al., 2010). The competitive balance within natural communities will change and there will be increases in invasive species (Hauer et al, 1997). Changes in ecosystem services and weather patterns may also affect the distribution and prevalence of vector-borne diseases, such as malaria and Dengue (Cardenas et al., 2006).

file:///F|/Dropbox/WaterHealthNew/Course2/discussion/WH20M001D001WRIHIntroduction.htm[11/1/2014 10:22:33 AM] WLC Template

Problem Formulation and Scoping the Current Situation (vulnerability, susceptibility, ethics, gaps and limitations)

Information Gathering - Situational Analysis

What is a Situational Analysis?

A situation analysis for a health district describes and analyses the situation regarding the health status and health services of a district. Information about different aspects of health and the health services is collected, in order to provide an overall picture of the district. At the district level, the situation analysis is primarily an assessment of the extent to which health services address health needs. It aims to describe an analyses of the situation, to explain what is happening and to identify factors which are facilitating or preventing progress in the district. As a result, it will also identify and highlight the priority problems and needs of the district so that plans and strategies for addressing these issues can be developed, and help to form part of a District Health Plan. Eventually, the situation analysis forms the basis of the District Health Report. (McCoy and Bamford, 1998)

Why do a Situational Analysis?

Information is required for effective district health planning and management. Conducting a comprehensive situation analysis of the district can be seen as a step in the collection and use of information. A well documented situation analysis (McCoy and Bamford, 1998) is helpful in a number of ways:

It forms the first step of a planning cycle for the health district (see the Figure below). Undertaking a situation analysis is therefore often the first task of a newly formed District Management Team.

By documenting the problems and proposed strategies of a district, it can be used as a monitoring and evaluation tool.

It can bring the different types and categories of health worker together in a teambuilding exercise whereby the DMT begins to work together and take responsibility for all the services in the district.

It can form the basis for the District Health Plan and the District Health Report. Subsequent reports can be regarded as updates and improvements of the situation analysis.

It identifies gaps or deficiencies in the information that is available, and in this way it contributes towards the development of a district health information system.

file:///F|/Dropbox/WaterHealthNew/Course2/discussion/WH20M001D003WRIHIntroductionQuestionnaires.htm[11/1/2014 10:22:33 AM] WLC Template

Image: situational analysis Source: McCoy and Bamford, 1998

Medical vs. Environmental Health approach.

Medical examination and diagnosis of health effects disease and acute or chronic condition. Environmental exposure questionnaire surveys, hazard identification, exposure pathways analysis and health risk assessment. Community health surveys of health outcomes. Social surveys of life styles cultural and behavioral factors.

Differences and similarities in the perspectives and applications.

Applications to water related impacts on health are addressed later in the Course in those sections dealing with epidemiology and human health and environmental risk assessment, and the section dealing with social surveys.

file:///F|/Dropbox/WaterHealthNew/Course2/discussion/WH20M001D003WRIHIntroductionQuestionnaires.htm[11/1/2014 10:22:33 AM] WLC Template

Water Quality

“Water is the driving force of all nature.”- L. da Vinci

“We forget that the water cycle and the life cycle are one.” Jacques Yves Cousteau

The quality of water depends on the origin of the source, the constituent properties of the water, the users and its use, as a receiving water of wash water and wastewater, and other sources of pollution.

Water quality is generally defined in terms of the biological chemical and physical contents of the water. The water often changes depending upon the season, the geographical area and whether polluting sources and pollutants are present.

Water quality is best understood in terms of monitoring and testing especially if the water is a source of drinking water, used for recreational purposes, industrial manufacturing and for use in agriculture and aquaculture.

Safe water for drinking and potable uses is necessary for the prevention of human disease and illness.

Drinking water should be of "potable use" water quality.

Water of potable water quality should be safe for use, as is, without the threat of acute or immediate disease or illness from contaminants in the water from its use for drinking and personal hygiene, in food preparation, and washing of fresh produce, dishes, utensils and food preparation surfaces.

Potable water would be safe for watering of livestock, and for most other uses, but may not be necessary or suitable.

Water quality requirements are generally the most stringent for drinking water and other "potable" uses, with the exception of uses needing sterilized water and ultrapure water such as, in invasive medical situations (labour and delivery, and surgery), vaccine production, and other pharmaceutical and ultrapure manufacturing processes.

Uses of water, other than for drinking water, are numerous and may have different levels of need for stringency of the level of water quality.

Some of the major uses of water can be categorized as:

1. Drinking water for human consumption (i.e., potable use).

2. Production of Food & Beverages

3. Agricultural use- direct watering of livestock

4. Agricultural use - irrigation of food crops

5. Fisheries and aquaculture

6. Industrial use - industrial processes such as, mining and metal smelting and refining, pulp and paper, oil and petroleum, industrial chemicals, energy production, textiles, waste treatment and disposal

7. Commercial - production of consumer products such as, toiletries and cosmetics, furnishing, clothing, cookware, art, electronics and IT equipment,

8. Sanitation and wastewater treatment - municipal and household use

9. Healthcare and medicine

Water Quality Properties

Salinity

pH - acidity and alkalinity of water; neutral pH is 7.0.

Hardness and conductivity

Turbidity - total suspended solids

file:///F|/Dropbox/WaterHealthNew/Course2/discussion/WH20M020D001WQPollution.htm[11/1/2014 10:22:33 AM] WLC Template

Colour

Taste and Odour

Other Contaminants - chemical, microbiological, biological, physical

These water quality properties are largely dependent on the origins of the source water and the presence of polluting sources (human and naturally occurring) that introduce contaminants into the water source.

For example,

Seawater and brackish water have a naturally occurring saline (saltwater) concentration and are UNSAFE for drinking water and potable uses, as high salt intake causes dehydration, kidney and organ failure and other health problems. Saltwater water cannot be used for watering livestock. Saltwater may not be suitable for watering home gardens and irrigation of crops, as high salt levels are detrimental to plant growth.

Water that has a pH outside of the acceptable WHO guideline for potable water quality is UNSAFE for drinking and potable uses, such waters have a noticeable taste (sweet water or sour water) and may be coloured, turbid, and contain potentially harmful substances leached into the water from the surrounding environment (sediment, rocks and minerals, water container, water distribution pipes).

A water hardness and conductivity beyond the acceptable WHO guideline for potable water quality is unsuitable for drinking and potable uses, and may be coloured, turbid and contain potentially harmful substances leached into the water from the surrounding environment (sediment, rocks and minerals, water container, water distribution pipes)..

Turbidity is an indicator of the water purity and reveals the presence of suspended solids (coarse particulates), such as originating from human and animal excreta, plant material, soil and sediment, and may contain potentially harmful substances.

Colour is an indicator of the purity of the water, filtered water that is coloured is a good indicator of the presence of dissolved materials and possibly suspended fine particulates, such as originating from human and animal excreta, plant derived dissolved organic material, soil and sediment, and may contain potentially harmful substances, may be smelly, aromatic, sweet or sour tasting.

Taste and odour are indicators of the purity of water and the presence of contaminants; bad and noxious odours indicate the presence of undesirable and potentially harmful substances.

Other contaminants can be introduced to water (surface, ground water, rainwater, wastewater) by various polluting sources from human activities, and also from naturally occurring sources, such as animal excreta, algal growth, volcanic activity, and severe weather and natural disasters like earthquakes and erosion.

Types of Pollution (examples) Sources (examples)

sanitary and storm water sewers; water treatment plant Sewage and municipal wastewater outfalls.

from soil erosion, heavy rains, flooding, landslides and earthquakes; overgrazing; clear cutting and logging; mining and construction activities; watercourse diversion and major water Sediment pollution - sand, silt and clay particles transported into waterways projects; hydroelectric dams; dredging; mixing zones of receiving waters of waste file:///F|/Dropbox/WaterHealthNew/Course2/discussion/WH20M020D001WQPollution.htm[11/1/2014 10:22:33 AM] WLC Template

waters and river basins; wave action, turbulence and scour due to heavy winds and storms, currents and tides.

animal wastes, fertilizer runoff, poor water circulation, low to Eutrophication -algal blooms, nutrient enrichment especially of nitrogen and no aeration, little mixing and phosphorous, increased BOD of surface water stagnation of waterways, warm water temperature.

wastewater holding ponds and wastewater outfalls from - metal mining and smelting; industrial chemical manufacturing; oil drilling; petroleum industry; quarrying; hydroelectric facilities; coal Wastewater - raw and treated fired power plants; incinerators, diesel generators, other combustion and industrial sources; commercial food processing facilities; fish processing and fish canning facilities; commercial manufacturing facilities.

from washing of contaminants off of land by water usage and rainfall and flooding such as, agricultural land and agricultural ponds (fertilizers, pesticides and animal wastes), land applied sewage sludge and biosolids, roads and parking lots, industrial and commercial sites, construction sites and residential properties; seepage from wastewater holding ponds (unlined and perforated); seepage from landfills; deep well injection of Surface runoff and groundwater infiltration waste materials; improper well drilling and well construction; quarrying operations; seepage and runoff from garbage, waste disposal, and recycling sites; spills; leaking storage containers (above and under ground), such as leaking and spills from storage containers of solvents, fuels, fertilizers and pesticide products, disinfectants; fire fighting activities including use and storage of flame retardants; shipyards, docks and marinas;

file:///F|/Dropbox/WaterHealthNew/Course2/discussion/WH20M020D001WQPollution.htm[11/1/2014 10:22:33 AM] WLC Template

septic systems.

ultrafine, fine and coarse particulates in air, acid gases and aerosol droplets from combustion sources, mining and metal smelters and refineries, coal fired power plants, pulp and paper facilities, waste incineration, construction and manufacturing Precipitation - fallout and deposition of dry particulate matter and washout and activities, vehicle exhaust; deposition of wet dissolved matter from the air - e.g., acid rain; deposition of in stone crushing, gravel and organic and organic air pollutants to surface waters and land; smog cement manufacturing; agriculture (soil tilling, seeding and harvesting operations), spraying of sewage sludge, spraying of liquid manure, pesticides and fertilizers; spray from cooling towers; and emissions from fires, explosions, volcanic activity.

nuclear power plants, weapons, medical facilities, Radioactive substances scientific research.

industrial and municipal wastewaters, wastewaters from Thermal pollution power generating plants, food processing plants.

human and animal excretions (vomit, urine, faeces); leachate from leaking septic beds; livestock holding areas and manure; rotting meat and spoiled food and food wastes; food production and food processing wastewaters; decomposing animal carcasses and corpses; wastewater from abattoirs and animal slaughter houses; offal and animal waste products including those derived from blood, bone, Fecal coliforms and other disease causing organisms skins, organs and other tissues; wastewater and spills of biohazardous waste materials (medical waste and medical processing water waters, dental wastewater and waste materials, veterinary wastewater and waste materials), biotechnology and pharmaceutical industrial

file:///F|/Dropbox/WaterHealthNew/Course2/discussion/WH20M020D001WQPollution.htm[11/1/2014 10:22:33 AM] WLC Template

wastes, sewage sludge and biosolids materials, leachate from cemeteries and burial grounds.

oil drilling, dredging, shipping traffic, weapon testing, Vibration and noise construction, turbine generators, pumping systems.

Key areas that will need to be address to protect water quality and quantity include:

1. water and urbanization

2. water and climate change

3. water resources and land use

4. drinking water and sanitation

5. water, agriculture and food security

6. water pollution, environmental degradation and disasters such as flooding and extreme weather events

7. improving transparency and cooperation with respect to water and agriculture

8. public health concerns regarding waterborne diseases

9. public hygiene, public safety and education

10. infrastructure and the financing of proper water resources

References:

Bartram, J. and Cairncross, S. 2010. Hygiene, Sanitation, and Water: Forgotten Foundations of Health. PLOS Medicine 7 (11): 1-9 e1000367 www.plosmedicine.org

Cairncross, S., Bartram, J., Cumming, O., and Brocklehurst, C. 2010. Hygiene, Sanitation, and Water: What Needs to Be Done? PLOS Medicine 7 (11): 1-7 e1000365 www.plosmedicine.org

Howard and Bartram, 2003. Domestic Water Quantity, Service Level and Health. World Health Organization, Geneva.

Hunter, P.R., MacDonald, A.M., and Carter, R.C. 2010. Water Supply and Health. PLOS Medicine. 7 (11): 1-9 e1000361 www.plosmedicine.org

Mara, D., Lane, J., Scott, B., and Trouba, D. 2010. Sanitation and Health. PLOS Medicine. 7 (11): 1-7 e1000363 www.plosmedicine.org

Pruss, A. Kay, D., Fewtrell, L., and Batram, J. 2002. Estimating the Burden of Disease from Water, Sanitatin, and Hygiene at a Global Level. Environmental Health Perspectives 110 (5):537-542

Prüss-Üstün A, Bos R, Gore F, Bartram J. 2008. Safer water, better health: costs, benefits and sustainability of interventions to protect and promote health. World Health Organization, Geneva.

file:///F|/Dropbox/WaterHealthNew/Course2/discussion/WH20M020D001WQPollution.htm[11/1/2014 10:22:33 AM] WLC Template

Point Sources and Non-Point Sources of Pollution (Chemical Biological and Physical)

Point Sources are fixed or stationary sources of pollution emitting contaminants directly to surface water, groundwater, air and land at a discrete point or location. Non-Point Sources are diffuse and mobile (non-stationary) sources of pollution involving the uncontrolled dispersal movement and deposition of contaminants and transported a distance from the origin, such as sediment movement, mixing zones in rivers and estuaries, combined pollution downstream of multiple sources and ambient air pollution.

If the contaminating substances (chemical biological and physical) are toxic and not rapidly broken down, degraded and destroyed or removed they may persist for an extended period of time (years to decades) making the water unavailable for any human needs.

The contamination of water by persistent accumulative and toxic substances, and microorganisms, and dissolved and suspended solids has a profound impact on both the quantity and quality of water in that area, and to surrounding areas connecting and adjacent to this body of water. These contaminants include,

Known and emerging human and animal pathogens (bacteria, viruses protozoa) and parasites.

Contaminants present in emissions in toxic quantities.

Nutrients (nitrogen, phosphorous, potassium, and carbon containing compounds and ions) and dissolved organic matter and totals suspended solids that promote

algal and bacterial growth, thereby accelerating eutrophication of surface waters.

depletion of dissolved oxygen and increase in BOD.

changes in water acidity, alkalinity, salinity, and in water temperatures.

the occurrence of foul and noxious odours and taste to water, fish and shellfish.

contribute TSS adding to sedimentation problems in receiving waters.

the attraction and breeding of invasive species and pests (e.g., insects, rodents, aquatic parasites), including those that are vectors of disease in animals and humans.

growth of pathogens -bacteria, viruses, fungi and protozoa.

Emissions of pollutants from point sources are generally more easily and effectively controlled and monitored than those from non- point sources.

Point Sources of Pollution

Examples of direct point releases into surface and ground water are, as follows, and these point sources should be treated before their release to minimize the introduction of pathogens and other contaminants to the environment:

Wastewater from commercial livestock, poultry, and aquaculture production and processing plants that can discharge pathogens in the wastewater into the environment. Wastewater outfalls from industrial facilities and municipal sewage and waste water treatment facilities. Leaking sewer pipes and underground storage tanks (USTs). Waste water holding ponds. Contained and controlled spills. Deep well injection of solvents and waste materials.

file:///F|/Dropbox/WaterHealthNew/Course2/discussion/WH20M020D002PtandNPtSources.htm[11/1/2014 10:22:33 AM] WLC Template

Non-Point Sources of Pollution

Precipitation (dry and wet), acid rain, surface runoff, mobile sources such as vehicles, transportation, erosion, wind carrying particulate matter and aerosols are examples of non-point sources of pollution. Contaminants in soils and sediments can move by surface run off, erosion, and leaching into nearby surface waters, and can move by seepage and infiltration downwards through the soil and overburden into the groundwater.

For example,

Pesticides in agricultural soils.

Drift from aerial spraying application of agrochemicals on croplands.

Microorganisms in manure and sewage sludges applied to land.

Spills and deliberate dumping of waste containing toxic metals, chemical solvents, biohazardous and radioactive materials into surface waters, onto land and injected into the ground, into wells and infiltrating bedrock.

Pollutants are also transported in the atmosphere and disperse during the application process, such as spraying of pesticides and sewage sludge, tilling agricultural soils, grinding of metals and rock materials, operation of incineration and combustion sources, especially under high velocity wind conditions.

Water bodies can also be contaminated with salts such as chlorides, sulfates, magnesium, calcium, and sodium. This occurs when the salt bleached from normally saline soils and delivered to adjacent water bodies.

References:

WHO, 2002. Guidelines for Drinking- Water Quality, 2nd Edition. WHO, Geneva. pp. 1-142.

WHO, 2004. Guidelines for Drinking- Water Quality, 3rd Edition. WHO, Geneva.

WHO. 2012. Water Safety Planning for Small Community Water Supplies. World Health Organization, Geneva, Switzerland. pp. 55.

file:///F|/Dropbox/WaterHealthNew/Course2/discussion/WH20M020D002PtandNPtSources.htm[11/1/2014 10:22:33 AM] WLC Template

Impacts of Pollution Sources on Environmental and Public Health

Increases in salinity can destroy the water body as a habitat for fish species and wildlife, and impact on the quantity and quality of potable drinking water, and water availability for other uses.

Waterborne pathogens arising from livestock production (animal wastes), food processing, and human wastes from poor sanitation and sewage treatment can have a profound influence on the quality of water. These pathogens bacteria, viruses, and fungi, and parasites can be introduced into the water by run off originating on feedlots or surface water flowing over pastures or fields were animal waste, human excreta, decomposing carcasses and garbage is present. Wastewater from commercial livestock, poultry, and aquaculture production and processing plants can discharge pathogens in the wastewater into the environment, and should be treated to minimize the release of pathogens and other contaminants.

The combination of contaminants emitted from both point sources and nonpoint sources can have profound environmental consequences that impact both upon environmental and public health.

These interconnected sources of water pollution make development and the implementation of remediation programs more problematic for limiting and controlling impacts of non-point sources and for preventing the movement of contaminants off-site. A multi-discipline, multi-barrier and integrated resources management approach based on the principles of risk assessment is warranted and should be followed up by monitoring and surveillance of important water quality parameters to provide assurances of the safety of water supplies for human health and potable uses, including watering of livestock and crops, as well as food production.

Monitoring and surveillance are applications necessary for assessing the safety and availability and sustainability of water sources and water systems such as for data on water quality parameter for indicators of the changes in properties of the water system, of local and regional pollutant releases by inventories from polluting sources, of the quantity of water usage, of health and vital statistics and other relevant information.

References:

Hoskisson, P.A. and J. T. Trevors. 2010. Shifting trends in pathogens on a changing planet. Antonie van Leeuwenhoek Journal of Microbiology. 98(4):423-427.

IOM (Institute of Medicine), 2009. Global Environmental Health: Research Gaps and Barriers for Providing Sustainable Water, Sanitation, and Hygiene Services. Washington, DC: The National Academies Press.

Kon, T., S. Weir, T. Howell, J. T. Trevors, H. Lee, J. Champagne, R. Brousseau and L. Masson. 2007. Microarry analysis of culturable Escherichia coli strains from interstitial beach water of Lake Huron, Canada. Appl. Environ. Microbiol. 73:7757-7758.

Kon, T, S. C. Weir, E. T. Howell, H. Lee and J. T. Trevors. 2009. Rep-PCR analysis of Escherichia coli isolates from recreational waters of South Eastern Lake Huron (Canada). Can. J. Microbiol. 55:269-276.

Mara, D. and N. Horan (Eds.) 2003. Handbook of Water and Wastewater Microbiology. Academic Press, NY.

National Assessment of Water and Wastewater Systems in First Nations Communities. Summary Report. 2004. Indian and Northern Affairs Canada.

OECD. 2003. Assessing Microbial Safety of Drinking Water: Improving Approaches and Methods. IWA Publishing, London, UK, pp. 1-279.

Teunis, P. F. M., G. J. Medema, L. Kruidenier and A. H. Havelaar. 1997. Assessment of the risk of infection by Cryptosporidium or Giardia in drinking water from a surface water sample. Water Research. 31: 1333-1346.

Waterborne Pathogens. 2006. AWWA Manual M 48. American Water Works Association, Denver, USA.

file:///F|/Dropbox/WaterHealthNew/Course2/discussion/WH20M020D003ImpactsPollution.htm[11/1/2014 10:22:34 AM] WLC Template

WHO, 2002. Guidelines for Drinking- Water Quality, 2nd Edition. WHO, Geneva. pp. 1-142.

WHO, 2004. Guidelines for Drinking- Water Quality, 3rd Edition. WHO, Geneva.

WHO. 2012. Water Safety Planning for Small Community Water Supplies. World Health Organization, Geneva, Switzerland. pp. 55.

file:///F|/Dropbox/WaterHealthNew/Course2/discussion/WH20M020D003ImpactsPollution.htm[11/1/2014 10:22:34 AM] WLC Template

What are Environmental Contaminants?

Environmental contaminants are chemical, biological, and physical.

Environmental contaminants are dissolved and particulate compounds that are released into the environment from human activities, by excretions from humans and animals (vertebrates and invertebrates), by plants, and microorganisms, and by seasonal and naturally occurring events and processes that alter the composition and amount of the chemical, biological and physical constituents and properties of air, water, soil and land, and food rendering it unsuitable and potentially harmful to human and animal health, and to ecosystem integrity and functions.

Changes induced by the presence of contaminants causing alterations in physical structure function and behavior can be detrimental to living organisms at the molecular-level, cellular- and tissue-level, whole organism-level, and also at the population- level, ecosystem-level and the geophysical-level and landscape-level.

Types of Contaminants Influencing Water Quality Quantity and Use

Three main types of contaminants influencing water quality quantity and its use are biological chemical and physical, including wet and dry precipitation of airborne pollutants, and soil and sediment particulates and dissolved organic matter.

In water, contaminants occur in dissolved, particulate, adsorbed and colloidal forms, including in water consisting of surface run off from soils, and pore water of sediments. Sediments and soils act as both a sink and a source of contaminants to water - surface water and ground water. Sediments and soils act as a sink through the removal of contaminants from solution in water by trapping (binding) settling accumulating and sequestering contaminants in the sediment bed and bulk soil. These removal process of binding and sedimentation generally make contaminants less accessible. Metal particulates (e.g., metal sulfides, metal oxides), and metals and organics compounds, including persistent organic compounds bind organic matter and to sediment and soil particles and become buried over time through the act of sedimentation. Contaminants in sediments, and soils, are released back into water through diffusion and ion exchange, resuspension of particulates by winds, turbulence, scour and wave action, and also sediment and soil mixing by the activity of biological organisms living, foraging and breeding in the sediments and soils such as, worms, insects, crustaceans, fish, mammals, birds, amphibians and reptiles. Algal and plant growth contribute to the removal of N, P, S, K, and C from the water column and algal and plant growth release oxygen to the water. Plants (aquatic macrophytes) provide surfaces and nutrients for microbial growth and for bacterial, fungi and detritivores and other biological organisms involved in the breakdown of organic matter and organic compounds. Plants create and alter habitats for animals, including providing habitats and protection for pests and beneficial molluscs, insects, spiders, amphibians, reptiles, mammals and birds.

Linkages to Humans and Aquatic Food Chains

Biological barriers (e.g., bacterial cell walls and membranes, plant cell walls, cell membranes) including multicellular mucous membranes of specialized tissues in animals and humans (e.g., lungs, blood vessels, nervous tissue, brain, blood-brain barrier and placenta) selectively allow only certain types of compounds to be taken up ( absorbed) in to cells and tissues and biological fluids. Generally, non-charged chemical compounds of smaller size are more soluble and are able to more easily passively diffuse across cell membranes than bulkier larger molecules, dissolved chemical complexes and particles. Some molecules because of their small size may be able to penetrate most cell membranes unassisted, entering into cells and into bacterial cells, and systemic circulation in plants, animals and humans. Compounds that enter systemic circulation in humans and animals are transported in the blood and lymph to tissues and organs away from the initial site of entry (e.g., skin, mouth, nose, throat, lungs) to more distal target tissues and cells where they can accumulate and exert their toxic effects. Ionic forms of chemical compounds, depending on their size and charge, may be inhibited from crossing cell membranes or may be actively carried into cells by binding to transport proteins and interacting with enzymes and other molecules. As well, large molecules and chemical compounds adsorbed onto particles may be carried into cells in the form of vesicles, by being surrounded and engulfed by cell membranes.

Shellfish and fish pass vast volumes of water across their gills and membranes, extracting nutrients and microorganisms and chemicals that are present in the waters and sediments in which they live, and POPs and persistent heavy metals accumulate in their tissues from contaminated waters and sediments. Many types of shellfish are detritivores, feeding of the bottom sediments and decaying plants and animal material including fecal material. Consumption advisories are often posted in areas known to have contaminated sediments, and immediately downstream of outfalls of point sources of pollution. Consumption restrictions and advisories are necessary prevent exposure to poisonous levels of toxins, metals, pesticides, persistence organic chemicals, and

file:///F|/Dropbox/WaterHealthNew/Course2/discussion/WH20M020D004TypesContaminants.htm[11/1/2014 10:22:34 AM] WLC Template

radionuclides, and other substances that are accumulated in tissues of filter-feeders, and fish, and sometimes in wildlife that eat them, such as water birds, water mammals, and marine mammals.

Disinfection of Pathogens

The structural activity and toxicity properties of different groups of chemical compounds have been exploited for use in disinfection of drinking water, contaminated surfaces in food and dairy production and processing areas, and hospitals and veterinary clinics, and in the antiseptic treatment in surgeries, childbirth and topical dressing for wounds for the prevention of infections.

The proportion of pathogens that are inactivated is dependent on the dose of disinfectant.

Dose of disinfectant necessary for the specified degree of inactivation = time of exposure X concentration of disinfectant

The shape of the survival curve of the pathogens when exposed to a disinfecting agent (e.g., UV radiation, chlorination) provides information about the mechanism of inactivation and from the shape of the survival curve it is possible to calculate the specified required dose to achieve a certain degree of inactivation. In adequate data for the characterization of survival curves can result in overestimation or underestimation of the dose of disinfectant necessary to achieve the required acceptable inactivation. Overestimation of the required dose may have undesirable consequences such as unacceptable toxicity of disinfectant residues to the user. Underestimation of the required dose for the necessary inactivation of the target pathogen may leave a harmful infectious level of pathogens remaining after treatment.

Dissolved organic matter, flocculating organic colloidal material and particulates in the water column provide nutrients and protection for pathogens and parasites. Therefore multiple barrier methods and filtration of water and cleaning of soiled surfaces to remove organic material before disinfection has been proven to increase inactivation of pathogens, and also decreases the amount of disinfectant needed to maintain an effective contact residual of disinfectant and the potential for harmful exposures to disinfection byproducts.

The disinfection of water is covered in more depth in the Course entitled Solutions Water and Waste Water Treatment.

Reference:

file:///F|/Dropbox/WaterHealthNew/Course2/discussion/WH20M020D004TypesContaminants.htm[11/1/2014 10:22:34 AM] WLC Template

Types of Environmental Contaminants

I. Biological Contaminants

Many biological organisms are intermediate hosts in the transmission cycle of zoonosis (animal-to-human transmissible disease) and vector-borne diseases (VBD). A common step in the cycle of disease involves the release of faecal matter and urine from humans animals and birds containing enteric microorganisms capable of causing disease into the water and sediments of lakes and rivers and ephemeral streams and ditches which serve as source waters for drinking water supplies. The release of other excreta (vomit, blood, sputum) and decomposing animal tissues and rotting meat into surface waters are also sources of human and animal pathogens and parasites.

Biological organisms, including plants and animals, and the decomposition of organic matter, provide a source of nutrients for the growth and proliferation and protection of disease-causing organisms.

Depending on the disease organism, exposure and disease transmission can occur through consumption of contaminated water use for drinking, personal hygiene (bathing, brushing teeth, washing), food preparation and cooking, agriculture and fishing and industrial and commercial purposes.

Microbial contaminants (enteric and non-enteric pathogens) include bacteria and amoebas, viruses, dinoflagellates, and protozoa.

Helminthes (parasitic worms), flies, trypanosomes and other parasites may be present in waters contaminated by animal and human wastes.

Cyanobacteria (blue-green algae) and algae contribute to the eutrophication of water bodies, and during seasonal periods of heavy growth, algal blooms release carbohydrates, nitrogen-based molecules, and reduced sulfur compounds to the water column; some cyanobacteria and algae produce toxins which harmful to wildlife and humans, causing liver toxicity, neurotoxicity, and gastrointestinal problems and may be carcinogenic when contaminated water is ingested and skin contact with toxins in contaminated water can cause skin irritation and sensitization.

Mosquitoes are well known insect vectors (vehicle) for transmitting vector-borne and blood-borne diseases, such as Malaria, Dengue Fever, Yellow Fever, and West Nile Virus.

Water snails are vectors for the disease Schistosomiasis (Guinea worm) that infects people working and wading in contaminated waters such as, during fishing activities and while working in rice fields.

Rodents and mammals - rats, mice, bats and other mammals that are carriers of infectious disease, frequently inhabit wetland areas, including docks and storage areas of shipping yards, and landfill and garbage dumps areas where there is garbage and composting materials containing rotting meat protein and food.

Poisonous snakes and spiders

Noxious and nuisance aquatic weeds

Reference:

Additional References:

Bartram, J. and Cairncross, S. 2010. Hygiene, Sanitation, and Water: Forgotten Foundations of Health. PLOS Medicine 7 (11): 1-9 e1000367 www.plosmedicine.org

Cairncross, S., Bartram, J., Cumming, O., and Brocklehurst, C. 2010. Hygiene, Sanitation, and Water: What Needs to Be Done? PLOS Medicine 7 (11): 1-7 e1000365 www.plosmedicine.org

Hoskisson, P.A. and J. T. Trevors. 2010. Shifting trends in pathogens on a changing planet. Antonie van Leeuwenhoek Journal of Microbiology. 98(4):423-427. file:///F|/Dropbox/WaterHealthNew/Course2/discussion/WH20M020D005BiologicalContaminants.htm[11/1/2014 10:22:34 AM] WLC Template