GIS-Mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo District, Kenya

2005:198 CIV MASTER'S THESIS

GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya

Jörgen Näslund Ingemar Snell

Luleå University of Technology MSc Programmes in Engineering

Department of Civil and Environmental Engineering Division of Sanitary Engineering

2005:198 CIV - ISSN: 1402-1617 - ISRN: LTU-EX--05/198--SE GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

SUPERVISORS

Sweden

Jörgen Hanæus Professor Division of Sanitary Engineering Luleå University of Technology 971 87 Luleå Sweden

Kenya

Susan Murcott Research Engineer Department of Civil and Environmental Engineering Massachusetts Institute of Technology 77 Massachusetts Avenue Cambridge, Ma. 02139-4307 USA

Peter Jacobsen Technical Advisor Catholic Diocese of Nakuru, Water Quality Programme P.O. Box 938 20100 Nakuru Kenya

KEYWORDS

Minor Field Study, Kenya, Nakuru, Lake Baringo, GIS, Fluoride, Groundwater

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

ACKNOWLEDGEMENT

This Master’s thesis constitutes our final degree project in Environmental Engineering at Luleå University of Technology, Sweden. The work was commissioned by The Ministry of Water, Nairobi, Kenya and Massachusetts Institute of Technology, USA. The project has been carried out as a Minor Field Study in Nairobi and Nakuru, Kenya during the period January – April 2005 and was completed in May –June in Luleå, Sweden. The field work was performed in Baringo District in the northern part of Rift Valley Province.

This project has throughout the time continuously undergone changes. Changes in form of object, area, time, supervisors, organizations and people involved. The time in Kenya has been challenging but also very profitable and we are grateful that we got the opportunity to work in this interesting country. Despite that the project developed in a slightly different way from what we planned for in the beginning we hope that the result of this study will benefit the people of Kenya and be useful for the involved organizations.

While working with this project we met and were introduced to many people. First of all we would like to send a great Thank You to our Professor, Jörgen Hanæus, at Luleå University of Technology for helping us with advice from Sweden. Also thanks for contacting and introducing us to Susan Murcott at Massachusetts Institute of Technology in the U.S. We would also like to thank the employees at the GIT (Geographic Information Technology) department in Luleå, especially Fredrik Salén, for the great support and supervising after we came back from Kenya.

For all help and support in Kenya we would like to thank Susan Murcott at MIT, Peter Jacobsen and the rest of the people at Catholic Diocese of Nakuru Water Programme. You really made our visit pleasant and enjoyable. Without you we would still be struggling with inadequate information.

Last but not least, we would like to thank the Swedish International Development and Cooperation Agency (SIDA) and Internationella Programkontoret for providing the main financial funding.

To all the helpful people of Kenya that we met along the road: Asante Sana, you will not be forgotten!

Luleå - Sweden, June 2005

Jörgen Näslund Ingemar Snell

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

ABSTRACT

This Master of Science thesis has been carried out in Nakuru and Baringo Districts in the Rift Valley Province in Kenya. The thesis was performed as a Minor Field Study (MFS) financed by the Swedish International Development and Cooperation Agency (SIDA), through the “Internationella Programkontoret”.

High fluoride levels in the ground water are a major problem that leads to diseases related to a high fluoride intake amongst people. In the Rift Valley Province, Kenya the bedrock consists of fluoride bearing minerals which contaminate the water. High levels are more common in deeply drilled boreholes than in surface water.

Catholic Dioceses of Nakuru (CDN) is a non – governmental organization stationed in Nakuru working with defluoridation methods to remove fluoride from drinking water. In 1985 they started a Water Programme with extensive activity within water supply and quality. In their continuous work a GIS- map over fluoride levels in boreholes would be useful. This thesis summarizes the work with creating a GIS –map. The map shows location and 6 other parameters of interest from 195 boreholes drilled by CDN.

Except from the work with the GIS –map this report also summarize results from a field study in an area around Lake Baringo in Baringo District. The aim with the field study was to investigate and overview the water situation. All in all 52 water sources were found, 7 permanent and 45 seasonal. The results and conclusions from the field study are presented in this report. They will hopefully facilitate the decision-making process for CDN.

A CD with data files concerning the GIS-map can be received from Division of Sanitary Engineering at Luleå University of Technology.

III

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

TABLE OF CONTENT

1 INTRODUCTION ...... 1 2 BACKGROUND...... 2 3 OBJECTIVES AND SCOPE...... 3 4 METHOD ...... 4 4.1 PREPARATORY STUDIES...... 4 4.2 GIS-MAP OVER BOREHOLES IN NAKURU DISTRICT...... 4 4.3 SURVEY OF THE WATER SITUATION AROUND LAKE BARINGO...... 4 5 DESCRIPTION OF AREA AND ORGANIZATION ...... 5 5.1 REPUBLIC OF KENYA ...... 5 5.1.1 Geographic Regions ...... 6 5.1.2 Climate...... 6 5.2 NAKURU DISTRICT...... 7 5.3 BARINGO DISTRICT...... 9 5.3.1 The area of investigation...... 10 5.4 CATHOLIC DIOCESE OF NAKURU...... 11 5.4.1 Background...... 12 5.4.2 Choice of defluoridation method ...... 13 5.4.3 CDN Defluoridation Filters ...... 13 5.4.4 Household Filter...... 14 5.4.5 Institutional Filter...... 14 5.4.6 Community Filter...... 15 5.4.7 Waterworks Filter...... 15 6 PERFORMANCE...... 16 6.1 PREPARATORY STUDIES...... 16 6.2 DATA COLLECTION ...... 16 6.2.1 Nakuru ...... 16 6.2.2 Baringo ...... 17 6.3 DATA AND MAP PREPARATION...... 19 6.3.1 Preparation of water characteristics data from CDN...... 19 6.3.2 Preparation of data from Baringo District...... 20 6.3.3 Preparation of digital spatial data layers ...... 20 6.3.4 Laboratory test methods ...... 21 7 RESULTS AND DISCUSSION ...... 22 7.1 FLUORINE...... 22 7.1.2 Field of utilization ...... 22 7.1.3 Fluoride in water ...... 23 7.1.4 Distribution on earth...... 23 7.1.5 Human exposure ...... 24 7.1.6 Health impacts and guideline values...... 25

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

7.2 FLUORIDE IN WATERS IN KENYA...... 26 7.3 REMOVAL METHODS ...... 26 7.3.1 Choice of defluoridation method ...... 27 7.3.2 Activated Alumina ...... 28 7.3.3 Nalgonda Method ...... 28 7.3.4 Reverse Osmosis...... 29 7.3.5 Bone char ...... 29 7.3.6 Chemical Processes in Fluoride Uptake on Bone Char ...... 31 7.4 NAKURU ...... 32 7.5 LAKE BARINGO ...... 36 7.6 SOURCES OF ERROR ...... 38 8 CONCLUSIONS ...... 39 9 RECOMMENDATIONS ...... 41 10 REFERENCES ...... 42 LITERATURE ...... 42 PERSONAL CONTACTS ...... 43 INTERNET ...... 43 APPENDICES APPENDIX 1 APPENDIX 2 APPENDIX 3 APPENDIX 4 APPENDIX 5 APPENDIX 6 APPENDIX 7

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

1 INTRODUCTION

It all started at the United Nations Millennial Summit in New York in 2000 and appeared again at the United Nations Summit on Sustainable Development in Johannesburg in 2003, the international community signed on to the Millennium Development Goals – a recommitment was made to sustainable development and the elimination of poverty. The seventh of the eight Millennium Development Goals is “to halve by 2015 the proportion of people without sustainable access to safe drinking water” (MDGs, 2004).

In this context, the World Health Organization (WHO) was seeking proposals from qualified bidders on research, assessment and implementation of household drinking water treatment and safe storage technologies in developing countries. At the June 2004 meeting of the WHO International Network to Promote Household Water Treatment and Safe Storage (the Network), participants worked to create an achievable operations plan for the next 12 months that will help promote simple, low cost initiatives to treat and safely store water at the point of use.

There have been three Network meetings in Geneva, Washington DC and Nairobi. Massachusetts Institute of Technology (MIT) faculty and staff from Civil and Environmental Engineering Department’s Master of Engineering Program have been involved and are playing a leading role in the activities of the Implementation Working Group. Since 1999 MIT has performed project work on household drinking water treatment and safe storage (HWTS) in five different countries. The 2004/2005 year’s “Water and Sanitation in Developing Countries” M.Eng. project was based in Kenya.

This Master’s thesis constitutes a small part of the MIT project in Kenya.

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

2 BACKGROUND

High fluoride intake has since long been known to cause serious harm to people’s health. Dental and skeletal fluorosis are two diseases that can be related to a too high and long exposure of fluoride.

There are various ways of getting exposed to fluoride. In developing countries with presence of fluoride bearing bedrocks people are often involuntarily exposed to fluoride by drinking contaminated water. In some rural areas in Kenya the water situation is often strained between rain seasons. Because of that groundwater from boreholes becomes an important source during most time of the year. Good quality surface water is often lacking and people are forced to travel long distances to find water.

In certain regions in Kenya problems with high fluoride content in the groundwater has led to a severe influence of fluoride related diseases among the people.

It has long been a big concern for the country and the problem is well-known to the Kenyan Government.

Measurements of fluoride levels throughout the country have been undertaken by the Ministry of Water and various non-governmental organizations for many years. The Ministry of Water in Nairobi holds a large quantity of data over the water situation in Kenya. The initial purpose for this study was that the Ministry of Water should support with data over the water situation (fluoride levels). Unfortunately the data was inaccessible for public due to the Kenyan bureaucracy. Instead data for this Master’s thesis became based on information from the Non-Governmental Organization (NGO), Catholic Diocese of Nakuru (CDN).

CDN is located in Nakuru and have run a water program for a little more than 20 years, mainly focusing on the area around the Rift Valley. When establishing new wells/water sources they file information about the source in the organization’s archive. Since CDN was part of the HWTS project and had been working on the fluoride issue for many years they had great knowledge about the complex water situation in the area. They had developed different types of water filters based on bone char a.o. for removal of fluoride and were running pilot experiments for other types of water purification.

The objectives were therefore based on desires from the Catholic Diocese of Nakuru in their continued work with improving the water situation and alleviate health hazards.

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

3 OBJECTIVES AND SCOPE

In this study there were three main objectives. One of them was a comprehensive preparatory literature studies to initially summarize earlier experiences about the complex water situation in the country, fluoride removal from drinking water, diseases related to fluoride etc. Topic related studies should be done not only before but also during the work in Kenya. The readings should comprehend on such breadth and depth that the understanding of the situation in Kenya was clear and problems within the project could be solved.

The second objective was to create a GIS-map over boreholes in Nakuru District. By using a GIS-software and borehole data from the Catholic Diocese of Nakuru a digitalized map showing boreholes in Nakuru District should be created. The map should show the location of the borehole and the specific fluoride levels in each well along with other water characteristics of interest. The goal with creating a GIS-map was to facilitate development work connected to prevailing water situation. In the present situation there is a need of getting a good overview of the water sources/boreholes for the government and the non-governmental organizations i.e. Catholic Diocese of Nakuru.

The third and last objective was to survey the water supplies in the area around Lake Baringo in Baringo District. The aim was to collect information about location, use and condition of the water sources and present it to the Catholic Diocese of Nakuru. The water situation in the area, in terms of availability and quality, was relatively unknown. The purpose of the field study was to create basic data for decision – making before implementing a new developed treatment plant for removal of fluoride. The gathered information should be put into the GIS-map as a spatial data layer.

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

4 METHOD

4.1 Preparatory studies The preparatory studies took place both in Sweden and in Kenya. Material was obtained from libraries but also from the Internet. In addition to the studies on printed material visits to different companies and communities working with water quality issues were carried out.

4.2 GIS-map over boreholes in Nakuru District Water quality data along with location and some user information data were received from the Catholic Diocese of Nakuru. The data were digitalized and unified and then presented on a digitalized map.

4.3 Survey of the water situation around Lake Baringo The survey of the water situation around Lake Baringo took place during a week-long expedition in the area. Different water sources were visited and people were interviewed about the source. Some water samples were collected and later analyzed for different parameters. Finally the location of each water source was set.

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

5 DESCRIPTION OF AREA AND ORGANIZATION

5.1 Republic of Kenya

(EBO, 2005) Kenya is located on the African continent’s east coast and covers an area of 582 646 km2. The capital is Nairobi and Kenya is bordered on the north by Ethiopia and Sudan, on the west by Uganda and Lake Victoria, on the east by the Indian Ocean and Somalia and on the south by Tanzania, see Figure 1.

Figure 1 Map over Kenya

The population who consists of more than 100 different ethnic groups comprises more than 31 million people of whom about 2,5 million lives in the capital Nairobi. More than half of the Kenyan population lives in poverty and resources are unevenly distributed, both between people and regions. The richest fifth of the population gets 50 percent of the income, while the poorest fifth gets 5 percent. High population growth, dry outs, floods and ethnical conflicts has worsen the living conditions for many Kenyans. Most of the poor people live in the rural areas but many of them moves to the bigger cities, where the slum increases. About half of the population has access to clean water.

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

5.1.1 Geographic Regions

Kenya has three main geographic zones; the highlands, the semiarid lowlands and the deserts. There is a fourth, called the coastal zone, which occupies a narrow strip along the Indian Ocean. There are 8 administrative provinces (see Figure 2) divided into 68 districts, all with its own district capital.

Figure 2 Map over Province Boundary

5.1.2 Climate Although Kenya is located on the equator most of the country has a temperate climate and that is because of the high altitude. Along the coast is the climate tropical. Kenya has two wet seasons and two dry seasons. The rainy seasons extend from March to May and from November to December. The precipitation is unevenly distributed over the country. The amount of rainfall is greatest in the highlands, located on the west, and in the coastal zones on the east side. The lowlands deserts of the north receive the least amount of rain.

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

5.2 Nakuru District

Nakuru district is located in the west province of Rift Valley and has a total population of 1 187 039 (EBO, 2005). Figure 3 shows the location of Nakuru district. The capital is Nakuru and the district is divided into 16 administrative subdivisions. Of the 7242 km2 land area 176 km2 constitutes surface water sources. In Nakuru like in many other districts in Kenya, water has become so scarce, especially surface water, making the only option to be ground water.

Figure 3 Map over District Boundary, Nakuru

The district can be subdivided into roughly three water basins namely Nakuru West, Nakuru North and Nakuru East.

Among the three, Nakuru West is generally endowed with a lot of streams traversing it. Nakuru West contributes a large part of the catchment area that drains into Lake Victoria. The area is seriously being affected by deforestation due to human settlement. Forest is cleared by those who settle in order to pave way for agricultural activities which has led to a change in underground water recharge.

On the Eastern side there are very few rivers. Most of the water sources consist of boreholes and shallow wells. 7

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

In the Northern side there are few streams and rivers which have little flow during the dry season.

Apart from rivers, streams and boreholes, there are also lakes, dams and pans. The lakes found in Nakuru district are; Lake Nakuru, Lake Naivasha, Lake Elementaita and Lake Solai. Lake Nakuru is a popular tourist attraction due to its flamingos and rhinos. Lake Naivasha is a fresh water lake and is important for horticulture and fishing. Lake Elementaita is like Lake Nakuru saline and famous for its flamingoes. Lake Solai is relatively smaller than the rest of the lakes and has also saline water.

Water in Nakuru is generally for domestic, livestock, industrial and irrigation purposes. In rural areas, water is generally for domestic and livestock while in urban areas it is for industrial purposes. The quality of water is fairly good especially the surface water in the Western part except for micro-organisms. In places where boreholes are the major sources of water i.e. the Eastern part, the fluoride levels have been noted to be high (CDN Handout, 2005).

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

5.3 Baringo District

(Ministry of Finance and Planning, 2002) Baringo district is located in the northern part of Rift Valley Province and has an area of 8,655 km2. 140 km2 of the area is surface water sources. Administratively, the district is divided into 14 divisions. The districts headquarter is located in Kabarnet and the total population for Baringo is 264 978 (EBO, 2005). Figure 4 shows the location of Baringo district.

Figure 4 Map over District Boundary, Baringo

Baringo District can be divided into three agro-ecological zones namely the highlands, midlands and lowlands. The highlands are characterized by hills known as the Tugen Hills that are at an average altitude of 2000 meters above sea level. The average annual rainfall is 1200 mm and the average annual temperature is 25°C. These conditions coupled with the fertile volcanic soils make the highlands conductive for crops and dairy farming. The midlands, where part of the field study for this report took place, are inhabited by agro-pastrolists, as rainfall is not adequate for crop farming. This area is endowed with the only three perennial rivers in the district namely; Perkerra, Molo and Kerio Rivers but none of them runs through the area of this study. The lowlands in the district have an average altitude of about 700 meters above sea level and most of it is rangeland. Temperatures in this zone are above 32°C and the 9

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study average annual rainfall is about 600 mm. These conditions are not conductive for crop farming and therefore livestock rearing is the main economic activity. Facts about Baringo district can be seen in Table 1.

Table 1 Baringo district facts Area Total area 8655 km2 Arable area 2515 km2 Non-arable area (including water masses) 6143 km2 Water mass 140,5 km2 Topography and Climate Altitude Highest 2300 meters Lowest 600 meters Rainfall Annual Average for long rains Highlands 900 mm Lowlands 500 mm Annual Average for short rains Highlands 300 mm Lowlands 100 mm Temperature range Highest temperatures January-March 35°C Lowest temperatures July 16°C Annual average temperature Highlands 25°C Lowlands 35°C

5.3.1 The area of investigation The area around Lake Baringo where the field study took place is located in the midland zone and covers an estimated area of 100 km2, see Figure 5. The physiographic and natural conditions are arid like the rest of the midlands. The majority of the people earn their living as agro-pastorals (goat farming) or fishermen. Another important income source for the area is tourists who come to see the wildlife and hot springs around the lake. Kampi ya Samaki, located at the western shore of Lake Baringo, is the main village with around 3500 inhabitants. The estimated population in the area covered in the field study was 6000 people. The infrastructure is poorly developed and large parts of the area are sparsely populated. Many people live in mud huts and poverty is widespread. Water scarcity is present throughout the year except for the rain seasons.

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

Figure 5 Map over the area of investigation

5.4 Catholic Diocese of Nakuru For this Master’s thesis; GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo, Kenya, there are three organizations involved except Luleå University of Technology; The Ministry of Water, Nairobi, Kenya; Massachusetts Institute of Technology, USA and Catholic Diocese of Nakuru, Nakuru, Kenya. The co-operation with CDN has been of great importance for the outcome of this report and because of that a circumstantial description of their organization is made in the following part of the report.

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

5.4.1 Background After a catastrophic drought that hit Kenya in 1984 the Catholic Diocese of Nakuru decided to create a Water Programme. The CDN Water Programme started in 1985 and serves the civil districts of Nakuru, Baringo, Koibatek, Kericho, Bomet and Buret. Kericho is a separate Diocese since 1995. Today the Programme employs around 60 people, as it has been growing during the years, and operates in several areas. Among the major are: drilling of deep wells, construction of water schemes and construction of rainwater harvesting water tanks. Figure 6 shows the sign outside the CDN office in Nakuru.

Figure 6 Sign outside CDN, Nakuru

During the work with implementing various water projects one of the objectives has been the provision of safe water. The water provided by the Programme was however not always safe. It became apparent that high levels of fluoride in the water made it unsafe for cooking or drinking, especially the water from deep boreholes.

The issue of high fluoride levels became a major concern for the CDN Water Programme and in 1997 the Programme applied to Misereor, Germany for a grant to develop methods for removal of fluoride for use in rural communities. In the beginning of 1998 the program started after the application was approved.

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

5.4.2 Choice of defluoridation method

When the CDN Defluoridation Programme started in 1998 it was not quite clear which defluoridation method to use. The bone char method seemed to have some interesting advantages in a rural setting but had not been implemented in a larger scale before.

The main advantages are:

• All material used are locally available, all chemicals and spares can be purchased in local hardware stores in Kenya. • The required regular maintenance is extremely minimal. There is no addition of chemicals, no cleaning is needed. • High efficiency, regardless of the amount of fluoride in the raw water. Practically all fluoride is removed. • Low cost • No hazardous chemicals used • No health risks involved.

However there are also some disadvantages using the bone char method:

• There is very little experience available using bone char in rural settings. A few pilot implementations had been made in Thailand and Tanzania, but no major implementation had been reported in the literature. • Regeneration of the filters when bone char becomes saturated requires caustic soda and acid and must be done by technically trained people, not by local communities. • Regeneration must be carried out regularly, perhaps a few times per year, depending on the size and usage rate of the system.

5.4.3 CDN Defluoridation Filters

When this report is written CDN offers four different types of filters

Household filters, small and large (10 – 40 liter/day) Institutional filters (50 – 500 liter/day) Community filters, 3 sizes (500 – 20,000 liter/day) Filters for water works (up to 2,000,000 liter/day)

Contact Precipitation is a new method under development at CDN in Nakuru, involving calcium and phosphate mixed in the water and reacting before the bone char is involved in the defluoridation process (Jacobsen P., 2005).

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

5.4.4 Household Filter The household bone char defluoridation systems are comprised of one or two 20 liters buckets depending on the design, see Figure 7. This filter is designed to supply a household (5 – 12 people) with fluoride free water for drinking and cooking. The filters are robust and inexpensive, but they do not utilize the filter material as efficiently as the community scale filters. The filter material can not be regenerated; it must be changed after saturation. The household filters are made in two sizes. The small type contains 12 liters of filter material and the bigger one contains 24 liters. The bone char filtration media reduces fluoride concentration from an initial concentration of 5 – 15 mg/l to less than 1.5 mg/l (Jacobsen P. 2005). Changing the media to new media in a household bone char filter is a simple process and requires no technical skill.

Figure 7 Household filters

5.4.5 Institutional Filter The institutional scale filters are designed for institutions or larger kitchens where filters can be connected to the normal water supply systems. These filters are constructed using standard PVC tanks of 650 liters, containing about 450 liters of filter material. The cost is currently 39,000 KES, not including installation. No regular maintenance is required; the daily operation does not differ from operating a standard water storage tank. Depending on the concentration of fluoride in the raw water and the filter size, the filter material needs regeneration or changing at regular intervals, typically every ½ to 3 years.

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

5.4.6 Community Filter The community scale bone char defluoridation systems supply 1,000 to 5,000 or more people with water for drinking and/or cooking. They are suitable where users collect their water at a central water point. The community plant is basically a 4 or 12 m3 ferro- cement tank filled with filter material and equipped with screen and connections for regenerating the filter. The structure is quite solid and suitable for public places, see Figure 8. The sizes range from 2,500, 5,000 or 10,000 liters of filter material (Jacobsen P., 2005). The appropriate choice depends on the consumption of water and the fluoride concentration in the water. As well as the institutional filter a community scale filter needs regeneration of the filter material when it’s saturated with fluoride. This should be done at regular intervals, typically every 3 – 23 month, depending on the consumption and fluoride concentration.

Figure 8 Model of Community filter

5.4.7 Waterworks Filter The waterworks scale bone char defluoridation systems are similar to the institutional or community filters but consists of two or more of the larger filters coupled in series. The filters are designed to be regenerated more frequently, every 2 to 8 weeks, but this can be done without disrupting the running of the defluoridation plant. Regeneration is carried out on one of the larger filters while the other ones are in use (Jacobsen P., 2005).

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

6 PERFORMANCE

In this section the methods used for preparatory studies, data collection and preparation and the water source investigation in Baringo will be explained more in detail.

6.1 Preparatory studies The search for literature about Kenya, fluorine and fluoride removal techniques in general started at Luleå University of Technology in December 2004. The studies took place at the University Library with access to all their material. Except going through books and articles in the library search for literature was done on the World Wide Web and in databases such as BiblioLine, GeoRef and Science Direct.

The preliminaries involved contacts with different companies and municipally representatives in Sweden familiar with the problematic of high fluoride levels in groundwater.

In Kenya, most of the initial time was spent getting to know the different organizations involved in the project. Among other things participation in a work shop held at Kenyan Water Institute and a visit to the Non-Governmental Organization ApproTEC were done. Some additional literature studies were carried out in Nakuru with material from CDN.

6.2 Data Collection The data collection can be divided in two parts. The performance when collecting data to the GIS-map in Nakuru and the performance when collecting data during the field study in Baringo.

6.2.1 Nakuru In Nakuru CDN kept a large quantity of data over boreholes in their archive. The amount of data was extensive considering the time available in Kenya for this project since the number of boreholes drilled and filed exceeded 360 at the time for this study.

The data files in the archive were reviewed and relevant information was photographed with a digital camera. In that way all necessary information could be stored in digital format and brought to Sweden without risk of loosing or missing some important information when leaving Kenya.

Some of the information from the files had already been documented by CDN so that information was also brought to Sweden and compiled with the new information.

To be able to present the borehole data in a clear way; good and accurate maps were needed. The intention was to get digitalized maps showing Kenya in general but Nakuru and Baringo districts in detail. The CDN Head office in Nakuru was visited as some earlier GIS work had been done by one of the employees. Unfortunately the 24 topographic maps from CDN´s previous work covered just parts of the required area and 16

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study were therefore not usable for this project. The Provincial Headquarter in Nakuru was also visited but only paper version maps were available. Due to regulations the maps could not be brought out of the office and were therefore impossible to digitalize. Also permits, which involve a difficult and time-consuming procedure to get, were required to be allowed to copy the maps.

As a last attempt to get digitalized maps some time in Nairobi was spent in meetings with authorized personnel at the Maji House. Information was given that one department at the Ministry of Water had worked on the preparation of digitalized maps. After two weeks spent running back and forth between the different departments the operation was cancelled with no successful outcome. The reason why the maps were inaccessible for this study is not clear. Either the Ministry of Water refused to hand out the information or the information did not exist. The first alternative is the most likely.

6.2.2 Baringo Data from the field study were collected during a week-long visit to the area around Lake Baringo. The geographic conditions in Baringo and the economic situation for this project made the way of transportation a key issue. After discussion and deliberation with CDN, bicycles seemed to be the best option.

To avoid getting lost a local guide was hired who also worked as an interpreter when interviewing the inhabitants. The area of investigation was located west of Lake Baringo, in Marigat, Bartabwa, Kabartonjo and Kipsaraman division. Starting point for the daily adventures was the village Kampi ya Samaki.

Both seasonal and non-seasonal water sources were visited during the research and great importance was put on the talks with users. An example of a shallow well is shown in Figure 9. People were interviewed about where they get water, how they use the water source, quality of the water, diseases related to the use of water, how far they have to walk/travel to the source etc. In addition to the information from the people, pictures were taken at some major water sources to emphasize the use of water. The gathered impressions for each water source were documented in a notebook along with the GPS coordinates and other information.

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

Figure 9 A shallow well outside Kampi ya Samaki

Except oral information 20 water samples were collected and later analyzed for electrical conductivity, pH, fluoride content, turbidity and settleable solids in the CDN laboratory. When there was water in the source the turbidity was estimated with a simple field instrument. There were desires from CDN that the microbial content in the drinking water should be determined but unfortunately that request was impossible to fulfill. It was not possible to bring the equipment for measurements of microbial content to the source. Heat in combination with the time to bring the samples to a laboratory would have made the results unreliable. The nearest laboratory was the CDN laboratory in Nakuru, by car hours away.

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

A Magellan GPS 320 (Global Positioning System) device was used to decide the position of all water sources, both seasonal and non-seasonal, see Figure 10. GPS is a fast and rather exact method and accurate enough for this type of investigation.

Figure 10 Positioning with GPS – device

6.3 Data and Map Preparation The outcome and quality of the GIS-map is all dependent on the quality of the data you put in. It is important to prepare the data carefully and uniform, especially when the work is to be continued by other users.

6.3.1 Preparation of water characteristics data from CDN After the data from the CDN files were reviewed, photographed and brought to Sweden it was compiled in an excel sheet together with the other data received from CDN. Not all data given from CDN was to be put into the map so some additional edits were done. A few parameters like Q-yield and tube material were left out since they did not constitute relevant information for this study.

To avoid mixing up data all names and characteristics given by the CDN were kept intact.

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

Certain portions of location data were given in degrees, minutes and seconds format (DDDMMSSS) while others were in degrees, minutes and hundredths of minutes format (DDDMMMMM). To unify all location data and to make them readable in ArcView they were transformed into WGS84 (World Geodetic System of 1984), decimal degree format, with assistance of a standard transformation system.

After all data were reviewed the table was converted into dBase IV format to be readable in ArcView.

6.3.2 Preparation of data from Baringo District From notes during the field study the collected data, location, type of source, type of construction, durability and number of users were transferred to excel sheets. Analyzes of the water samples performed by CDN were added to the other data. After putting all information into the excel sheet the sequence of work for making the data readable in ArcView was the same as the procedure for water characteristics data from CDN.

6.3.3 Preparation of digital spatial data layers The spatial data layers over Kenya were acquired from ESRI’s Data & Maps 2000 CD. There were no maps found that only covered Kenya, Nakuru and Baringo on the CD so the world map was used. On the world map there are many options for the spatial data layers although the detail abundance is not very good.

The information kept in dBase IV format was converted to ArcView shape files. Wells location and additional parameters for Nakuru and Baringo District were prepared with the help of ArcView.

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

6.3.4 Laboratory test methods The water samples from Baringo field trip were analyzed by the employees at CDN laboratory, see Figure 11. Same test methods as the samples collected by CDN (from boreholes) themselves were used.

Figure 11 Staff at the CDN laboratory

The test methods follows the "Standard Methods for the examination of Water and Wastewater" published by American Public Health Association and American Water Works Association.

Turbidity test -Nephelometric Method (Standard Methods, 1995, 2130B) Electrical Conductivity - Ele Paqualab operating instructions pH Value - Electrometric Method (Standard Methods, 1995, 4500-H+A) Fluoride test - Ion Selective Method (Standard Methods,1995, 4500-F-C) Settleable Solids - Volumetric Method (Standard Method, 1995, 2540F)

Equipment: ELE Paqualab Turbidity meter ELE Paqualab Conductivity meter Metrohm 713 pH meter Fluoride (ion selective) electrode: Solid state membrane, Metrohm no 6.0502.150 Reference Electrode: Glass membrane, Metrohm no 6.0733.100 pH meter (mV meter): Metrohm 713 pH meter Imhoff cone

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

7 RESULTS AND DISCUSSION

Below follows the results of this study. The preparatory studies started in Sweden in January 2005, before the three months of field work in Kenya, and lasted until June when the report was completed. The literature study comprised studies about Kenya, fluorine and its field of application, removal techniques, health hazards and guideline values. The results from the preparatory study are given in chapter 7.1 to 7.3. In chapter 7.4 the results from the GIS-mapping of the boreholes in Nakuru are presented and last, in chapter 7.5, the results from the field study in Baringo District are presented.

7.1 Fluorine

Fluorine (F2) is in its elementary form a greenish, highly reactive, diatomic gas. It has atomic number 9 in Mendeleyev’s Periodic Table and is the most reactive and electronegative of all known elements. Because of its high reactance fluorine rarely occurs free in nature. It generally combines with other elements to form fluorides and is normally found as the fluoride ion (F-) in minerals.

Information about the fluorine proportion in earth’s crust differs in almost every report. Among others the Ministry of Health in New Zealand uphold that it is 17th most common element in the earth's crust and that earth’s crust contains about 900 parts of fluoride per million (ppm) (MoH, 2005). Others uphold that it’s the 13th most abundant (Gikunju, J.K. et al., 1992) and comprise 0,065 – 0,07 % of the earth’s crust (NE, 2005, Dicciani N., 2003).

There are only two rock-forming minerals, topaz (Al2SiO4(F,OH)2 ) and fluorite (CaF2), that have fluorine as an essential part in their formula.

Other minerals with fluorine as a major component are: fluorspar or fluorite (CaF2), cryolite (NaAlF6) and fluorapatite (3Ca3 (PO4)2CaF2). Those minerals are common accessory minerals in various rock formations; fluorspar in limestone and sandstone (sedimentary rocks) and cryolite in granite (igneous rocks) (Bulusu K.R. et al., 1979). Fluorapatite, by far the commonest of the apatite group, is present in almost all igneous rocks and many of the sedimentary and metamorphic rocks (Deer W.A. et al., 1966).

7.1.2 Field of utilization Although fluoride has many fields of applications it is perhaps most commonly known as a component in toothpaste, where it works as a beneficial agent. It is proved that low levels of fluoride provide some protection against caries, which is the main reason for adding fluoride to toothpaste.

In 1945 early observations of fluoride’s caries prevention properties led to experimental addition of fluoride to drinking water in several countries. According to Grandjean [1982]

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study in 1982 more than 200 million individuals received artificially fluorinated drinking water worldwide, with 95 million of them residing in the United States.

Fluorochemicals also underscore a wide range of commercial successes. Growth in the industrial and household refrigeration and air conditioning industries is based largely on the use of low-toxicity, nonflammable, and energy-efficient fluorocarbon fluids. Fluoropolymers and fluoroelastomers are used widely in homes, buildings, automobiles, aerospace applications, and wherever high performance such as excellent thermal, flame, electrical, chemical, and solvent resistance and low oxygen and moisture permeability is required (Dicciani N., 2003).

7.1.3 Fluoride in water Since some fluoride compounds in the earth's upper crust are soluble in water, fluoride is found in both surface waters and groundwater. In streaming surface freshwater, fluoride concentrations are usually lower than in groundwater because the shorter contact time between water and rock. The natural concentration of fluoride depends on the geological, chemical and physical characteristics of the aquifer, the porosity and acidity of the soil and rocks, the temperature and the action of other chemical elements (UNICEF, 2005).

Another reason for high fluoride concentrations in groundwater can be the absorption of uprising, subterranean gas containing high levels of fluoride (Deer W.A. et al., 1966).

7.1.4 Distribution on earth Fluoride bearing bedrocks and fluoride contaminated water occurs in all parts of the world including large parts of Africa, China, the Middle East and Southern Asia, see Figure 12. There are 2 major belts with known high fluoride levels where extensive studies have been carried out. One belt is the East African Rift from Eritrea to Malawi and the other is the belt which stretches from Turkey through Iraq, Iran, Afghanistan, India and northern Thailand to China. The Americas and Japan have similar belts but with generally lower fluoride levels.

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

Figure 12 Map over countries with endemic fluorosis due to excess fluoride in drinking water

Fluoride is often found in higher concentrations in areas where there have been volcanic activities. In the Kenyan Rift Valley the bedrock and soil consists of Quaternary and Tertiary volcanics and unconsolidated sediments (Gaciri S.J. et al., 1993), both rich in fluoride bearing minerals (Nanyaro J.T. et al., 1984).

Despite the frequent occurrence of fluoride, its wide field of applications and broad extension throughout the world the essentiality for humans has not been demonstrated unequivocally. On the contrary, many studies on the adverse effects of a too high fluoride intake have been carried out and the knowledge of the diseases related to the problem is good.

7.1.5 Human exposure There are various ways of getting exposed to fluoride. The World Health Organization list in their monograph “Fluorides in Drinking Water” (Fawell J.K., 2003) 4 different ways; Air, Water, Food and Dental uses. When searching for material it seems like most studies have been done for the water way of exposure.

In Kenya, when talking to authorized people in the Ministry of Water and other water organizations concerning exposure way, water overshadows the other ways. The anxiety is supported by Fawell J.K. (2003) considering that: “In areas with relatively high fluoride concentrations in groundwater, drinking-water becomes increasingly important as a source of fluoride” (Fawell J.K., 2003).

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

7.1.6 Health impacts and guideline values Because the fact that fluoride is widely dispersed in the environment, all living organisms are extensively exposed to it and tolerate in modest amounts. In humans, overexposure of fluoride results in accumulation of the element in the mineralizing tissues of the body. The symptoms become visible even with small exposure. In young people fluoride accumulates in both teeth (dental fluorosis) and bones (skeletal fluorosis) while in older people overexposure of fluoride causes skeletal fluorosis only. Figure 13 shows a boy with dental fluorosis. Results of examination of children’s teeth in Njoro Division, Nakuru District show that 48,3% of the children suffer from moderate to severe dental fluorosis (Nyaora Moturi W.K. et al., 2001).

Figure 13 Boy with dental fluorosis, Kampi ya Samaki Primary School

Skeletal fluorosis is a complicated illness with a number of stages. The first two stages are preclinical where changes have already taken place but with no notable pain or symptoms for the patient. The next two stages are clinical where symptoms include pains in the bones and joints; sensations of burning, pricking, and tingling in the limbs; muscle weakness; chronic fatigue; and gastrointestinal disorders and reduced appetite (FAN, 2005). When exposed to a very high level of fluoride intake under a longer time skeletal fluorosis can grow in to the most severe form, crippling skeletal fluorosis. In crippling fluorosis the extremities become weak and moving the joints is difficult.

Also dental fluorosis occurs in different stages. There are two indexes; Dean’s Fluorosis Index (Dean H.T., 1942) and TF (Thylstrup-Fejerskov) Index (Thylstrup A. et al., 1978), which describes the severity of the illness. Both Dean’s and Thylstrup-Fejerskov’s Index have different levels from not visible signs to severe affected enamel (FAN, 2005).

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

The reason why children become affected by dental fluorosis while adults don’t is the mineralization of teeth which takes place at about 22-26 months of age (Fawell J.K., 2003). During that period children are extra sensitive and a damage that occurs lasts for the rest of their life.

Numerous, all by each other independent studies have proved relations between fluorosis and daily intake of fluoride. Manji et al. (1986) showed in his study about dental fluorosis in an area with 2 ppm fluoride in the drinking water that 50% of the children had pitting in their teeth exhibiting a TF Index level of 7 or higher (Manji F. et al., 1986). The level of fluorosis is not entirely connected to a certain level of fluoride in the drinking water. The effects depend on the total intake and vary between people.

The World Health Organization has recommended a guideline value for drinking water of 1,5 mg F/l. It was set in 1984 and reaffirmed in 1993 and 2004. Drinking water with concentrations above this value carries an increasing risk of dental fluorosis. Much higher concentrations lead to skeletal fluorosis. In Kenya the Kenya Bureau of Standards follows the WHO guideline value and recommends a maximum of 1,5 mg F/l for drinking water (Gikunju J.K. et al., 2002).

7.2 Fluoride in waters in Kenya The catchment basins in East Africa are composed primarily of basic volcanic rocks; therefore fluoride is likely to be present in water in these areas (Gikunju J.K. et al., 1995). Clear and accurate information about the situation with fluoride in natural waters of Kenya today is somewhat difficult to find. Extensive studies have been carried out by different research teams during the last 50 years but most of them are dated between 1960 and 1990. Later studies focus most on the effects of fluorosis among the population and/or levels of fluoride in certain district or subdistricts in Kenya. Some papers show results from studies made on different water sources; river water, streams/springs, tap water, boreholes or rain water. Any literature about comprehensive studies done recently has not been found. In interviews with people responsible for water quality at the Department for Water and Pollution Control in Nairobi it was found that the awareness of the problems associated with high fluoride levels in drinking water is good. Also the awareness of which regions in the country that have particularly severe problems is good. On the other hand, the knowledge about the fluoride level of a specific water source in a certain region is lacking.

7.3 Removal methods Several methods for removal of fluoride from drinking water have been described in the literature, but only a few are used in praxis. The methods differ from each other in technique, arrangement, performance and material. The process of removal of fluoride is generally termed as defluoridation or defluorination.

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

7.3.1 Choice of defluoridation method When evaluating the effectiveness and suitability of a method one has to know the condition in which the defluoridation plant will be used. Defluoridation in a remote rural village obvious requires another approach than in a water work for a big city. When selecting a defluoridation method the following parameters should be considered.

• Efficiency: o Can the defluoridation reduce the fluoride level to acceptable values (i.e. below 1, 5 mg F/l)? • Running of the plant: o Level of required supervision, dependency of electricity, complexity of operation (i.e. dosing of chemicals). • Cost of defluoridation, both with respect to establishing the plant and to the running costs. • Maintenance of the plant, costs and availability of spare parts. • Possible negative impacts (i.e. hazards): o Handling of dangerous chemicals, consequences of wrong dosing of chemicals, inefficient fluoride removal and possible chemical residual in the treated water. • Supply of chemical for defluoridation.

The selection of method should reflect the local situation and none of the method could be termed as best without careful consideration of all points. The choice of method is therefore dependent on the local possibilities. The defluoridation techniques, based on the nature of processes, can be grouped under following categories (Mariappan P. Unknown):

• Adsorption and Ion exchange • Precipitation • Electrochemical method and • Membrane Technique

The materials and methods for defluoridation are tabulated in Table 2.

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

Table 2 Material and methods to remove fluoride Adsorption Ion exchange Precipitation Others Carbon Materials NCL polyanion Lime Electrochemical Wood, Lignite Resin Alum (Aluminium Coal, Bone Tulsion A27 Lime and Alum electrode) Petroleum Lewatit-MIH- (Nalgonda Electrodialysis residues 59 Technique) Reverse Osmosis Nut shells, Pady Amberlite IRA- i) Fill and Draw husk 400 ii) Continues flow Avaram bark Deacedodite iii) Package Coffee husk, Tea FF-IP Treatment plant for waste Waso resin-14 HP Jute waste Polystyrene Alum floc blanket Coconut shell method Coir pith, Fly ash Poly aluminium Carbion, chloride (PAC) Defluoron-1 Poly aluminium Defluoron-2 hydroxy sulphate Activated alumina (PAHS) KRASS, Bauxite Serpentine Clay minerals Fish bone, Calcite Bio-mass

7.3.2 Activated Alumina Activated alumina is the most successful and the most often used absorbent for fluoride removal. Boruff was the first man to study the absorbent properties of activated alumina in 1934 and contact beds of activated alumina have now been used for many years in municipal water treatment plants for removal of fluoride. In many cases activated alumina appears to be technically feasible and economically viable. It is available in a range of granule sizes and is able to adsorb as much as 1,4g fluoride per 100g product (Azizian F., 1993). At normal pH values fluoride is absorbed from and hydroxide is released to the water. For regeneration the process can be reversed by raising the pH values. Main advantages are the simplicity of normal operation and the efficiency; fluoride can be reduced to practically any desired levels.

7.3.3 Nalgonda Method In the Nalgonda method alum and lime are added to the raw water. Fluoride attaches itself to the flocs of aluminum hydroxide, which are formed and can be removed from the water together with precipitated flocs (CDN Handout, 2005). The use of the Nalgonda method has apparently had some success in India and the method can be implemented both in households and in water works (NEERI, 1987). The main advantages in the Nalgonda technique are, its low cost and the availability of the lime and alum. There are some major drawbacks like the lack of required efficiency, the requirement of adding 28

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study chemicals continuously and the high amount of residual sulfate in the treated water. This is especially the case when the fluoride content in the water is high.

7.3.4 Reverse Osmosis Reverse osmosis should be regarded as quite an advanced technology and is probably suitable for large water works or special applications only. Maintenance requires access to spare parts and chemicals, which are not likely to be available in rural areas. In this method the water passes through a membrane that holds back some of the salts (i.e. the fluoride) in the water. The principle of reverse osmosis is quite simple but the practical implementation is more complicated. This is due to the relatively high pressure required to force the water through the membranes. Also it is often required to do the osmosis in several steps, i.e. a pre-filter to remove the hardness from the water is often necessary. A major advantage of reverse osmosis is the fact that the general level of salts is reduced; hence in areas where high salt content in the water is a problem it might be the only option for providing drinkable water.

7.3.5 Bone char Bone char or bone char gravels are bones, which have been heated to high temperatures, above 400 degrees Celsius, and crushed (Jacobsen P., 2005). Bones before heating are shown in Figure 14 and bone char gravels can be seen in Figure 15.

Figure 14 Bones before heating

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

In the process, all organic materials are removed and only the mineral content, apatite Ca5(PO4)3(F,Cl,OH), are left.

Figure 15 Bone char as gravels

Due to its porous structure this material is able to absorb high amount of fluoride. A bone char filter is simple to operate and has a high efficiency; the major problems are connected to the regeneration. Bone char can be regenerated by raising the pH in a process similar to the regeneration of activated alumina. An alternative method of extending the lifespan of the bonechar is by washing the bone char at regular intervals with a solution of calcium and phosphate, known as surface coating, or continuous adding small amount of calcium and phosphate to the raw water; contact precipitation. This kind of method requires that the bone char can be produced locally or else the availability of bone char can be a serious problem. Except for the implementation of bone char defluoridation systems in the Rift Valley Province, Kenya there are only few reported examples of defluoridation using bone char, including a few plants in the USA and some pilot projects with household filters in Thailand and Tanzania

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

7.3.6 Chemical Processes in Fluoride Uptake on Bone Char (Bregnhøj H., 1995) The process that leads to immobilization of fluoride on bone char is complicated and a combination of two or more reactions. The reactions vary with fluoride concentrations, pH and available surface area. The reactions involved can be divided into four types;

• Ion exchange • Adsorption • Recrystallization • Precipitation

There are two types of ion exchange taking place. Either when a fluoride ion changes position with a hydroxide ion (OH-) or when it exchanges with a carbonate or a 2- - hydrocarbonate ion (CO3 /HCO3 ).

− +−↔+− OHFBCFOHBC −

The chemical reaction for the ion exchange between fluoride and carbonate is more difficult to explain. Carbonate can exist in different forms and positions in bone char. Due to Bregnhøj (1995) the exchange between fluoride and the carbonate ion in the OH- -position is the most likely reaction.

Adsorption is a very comprehensive term including many different types of chemical processes which in their widest extend include all processes where the adsorbate connects to the adsorbent surface. In adsorption of fluoride on the bonechar surface, fluoride seems to attach to vacant sites. Initially the reaction is fast with no sign of release of OH-.

In the recrystallization process the Hydroxyapatite, HAp, and bone mineral dissolve and precipitate with fluoride as Fluorapatite, FAp. When the recrystallization process depends on the difference in solubilities of Hap and FAp, the process is likely to take place in water with fluoride concentrations above 1,5 mg/liter.

When calcium and phosphate is added to fluoride containing water in concentrations exceeding the solubility product for FAp or CaF2 it is theoretically possible for it to precipitate. Although bone char can work as a catalyst in the precipitation process, precipitation is not presumably important in conventional bone char defluoridation. Precipitation can though be utilized if calcium and phosphorus is added to the water.

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

7.4 Nakuru All in all 195 out of 358 boreholes from the CDN files fulfilled the criteria of having either water quality data; reliable coordinates or both water quality data and coordinates. Out of the 195 boreholes, 22 completely missed coordinates, 4 had coordinates given in some local grid-system and another 31 had coordinates difficult to interpret. Despite the lack of location data for some boreholes all boreholes with coordinates in interpretable format were put on the GIS-map. A table with complete data for all 195 boreholes can be seen in Appendix 2.

The well identification numbers (WELL – ID) ranged from D004 to D358 but with number D338 as the last complete borehole, having both water quality and location data.

The boreholes were mostly located in Nakuru District but also in other districts. The loss of district borders on the map made the exact number of boreholes in each district hard to assess. Coordinates ranged from east 34°04’28 (borehole D110) to 39°45’00 (D029) and from south 01°48’30 (D232) to north 02°23’01 (D072).

The water quality data from the laboratories showed about 30 different parameters. For this project pH, electrical conductivity and fluoride level were studied. The pH values ranged from 6,0 (D299) to 9,3 (D139) and the electrical conductivity [mS/m] from 8 (D143) to 640 (D085). An extract from Appendix 2 with data from context above can be seen in Table 3.

Table 3 Table with data from CDN´s boreholes WELL DEPTH F ID N/S E/W PROJ.NAME PEOPLE [m] pH COND [mg/l] D029 00 29' 00 36 17' 40 St. Peters Prim. 1950 120 6.00 24 1.9 D072 02 23' 01 35 38' 46 Lokichar 700 60 7.70 64 0.3 D085 01 13' 50 35 45' 40 Lomelo Mission 400 50 8.00 640 0.1 D110 00 47' 02 34 04' 28 Rakwaro 400 80 6.30 16 0.6 D139 00 16' 12 36 32' 13 Rumuruti Mission 400 110 9.30 72 4.6 D143 00 10' 15 36 21' 00 Elite school II 600 120 6.60 8 0.2 D229 01 17' 00 39 45' 00 ICRC-Arthi Bohol N/A 105 8.00 272 1.4 D232 01 48' 30 35 42' 45 Ilkerin-Loita IDP N/A 130 7.30 102 1.9 D251 00 17' 27 36 04' 20 Bishop's House N/A 120 9.20 320 40.0

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

Fluoride, the parameter of greatest interest for this study, had big variations between boreholes. The highest fluoride content was found in borehole D251 (40,0 mg F/l) while the lowest (0,1 mg F/l) was found in several boreholes, i.e. D085. 84 of the 195 boreholes (43,0 percent) represented values below the WHO’s approval guideline value of 1,5 mg F/l, see Figure 16.

Figure 16 Map over water sources with Fluoride < 1,5 mg/l

24,1 percent or 47 of the boreholes represented values between 1,5 – 3 mg F/l, see Figure 17

Figure 17 Map over water sources with Fluoride 1,5 – 3 mg/l 33

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

26,7 percent or 52 of the boreholes represented values between 3 – 10 mg F/l, see Figure 18.

Figure 18 Map over water sources with Fluoride 3,0 – 10,0 mg/l

6,2 percent or 12 of the boreholes represented values over 10 mg F/l, see Figure 19.

Figure 19 Map over water sources with Fluoride > 10,0 mg/l

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

The compilation shows that more than half of the measured boreholes had values that could lead to some kind of effect on humans’ i.e. dental or skeletal fluorosis. The distribution of fluoride levels between boreholes are illustrated in Figure 20.

Fluoride Distribution 6%

27% < 1,5 mg/L 43% 1,5 - 3,0 mg/L 3,0 - 10 mg/L > 10 mg/L

24%

Figure 20 Fluoride levels distribution between CDN boreholes

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

7.5 Lake Baringo In the area west of Lake Baringo 52 water sources were target and tagged with a GPS. The sources were divided into rivers, pounds, shallow wells, boreholes and Lake Baringo. Of the 52 water sources 27 were connected to rivers, 18 to pounds, 3 to shallow wells, 3 to boreholes and one to Lake Baringo. The area that was covered by the research totalled 100 km2. Because of the season there were only 21 samples taken for evaluation. The other sources were dried out. The coordinates and water quality data carried out from the samples were put into a GIS - map.

The pH values differed between 6,86 – 8,73 and the electrical conductivity [mS/m] from 5 – 128. Due to forthcoming projects that are under development by CDN there were interests of knowing about settleable solids. Settleable solids were less than 0,05 ml/250ml in all samples except in river 8; 42 ml/250ml, and pound 4; 40 ml/250ml. The high levels of settleable solids in river 8 and pound 4 are probably depending on rainfall during the night before the samples were taken. There is a wash – out where soil particles follow the rain water during the first hours of rain.

The fluoride levels were relatively low in most of the cases but Lake Baringo showed high content and that is a big problem because that’s the most important source for water collection in the area. 66,7 percent or 14 of the water sources showed values up to 1,5 mg F/l, see Figure 21.

Figure 21 Map over water sources with Fluoride < 1,5 mg/l

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

23,8 percent or 5 of the water sources showed values between 1,5 – 3 mg F/l, see Figure 22.

Figure 22 Map over water sources with Fluoride 1,5 – 3 mg/l

9,5 percent or 2 of the water sources showed values over 3,0 mg F/l, see Figure 23.

Figure 23 Map over water sources with Fluoride > 3,0 mg/l

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

The water sources that keep the fluoride levels under WHO’s approval guideline value 1,5 mg F/l represent mostly seasonal sources. Generally surface water is low in fluoride concentrations. More than 95% of the surface water sources in the world contain less than 1,5 mg F/l (Phantumvanit P. et al., 1988). All of the measured fluoride values that exceed levels for effect on humans are from permanent water sources. The distribution of fluoride levels between the collected water samples is illustrated in Figure 24.

Fluoride Distribution

9% 0%

< 1,5 mg/L 24% 1,5 - 3,0 mg/L 3,0 - 10 mg/L > 10 mg/L 67%

Figure 24 Fluoride levels distribution between water sources, Lake Baringo

7.6 Sources of error In this study there were very few possibilities to check the accuracy of the data from the files. The laboratory experiments for water quality had been performed both by the Ministry of Water in Nairobi and at the CDN Laboratory in Nakuru. All of the water samples analyzed by the Ministry of Water were dated from 1990 to 1999 while CDN seem to have done most of the analyses from 1999 up to present. None of the laboratories are ISO-certified and analytical methods from the Ministry of Water’s laboratory during the time 1990-99 are unknown although study visits to the laboratory have been undertaken.

Another source of error from the CDN files is how the positions of the boreholes (coordinates) have been determined. When interviewing people at the CDN, information was given that at least 3 different people hade been working with positioning of the boreholes throughout the time period (1990-2005). In some files the position was given in a local grid system, while in others coordinates were incomplete. It came to light that a GPS device had only been used for the last 3-5 years.

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

8 CONCLUSIONS

Kenya is a country with a challenging water situation. There are many reasons why fresh and safe water is insufficient in large parts of the country. Climate varies considerably within the country with hot and dry conditions in most places except for the coastal zones and in the highlands. Near the coast the climate is tropical and in the highlands it is temperate with large amounts of rain annually, although unevenly distributed over the year. While the water scarcity in the arid areas makes living conditions for people tough it is not their only concern. Where there is water, and especially in the Rift Valley Province, the quality is often insufficient. High fluoride levels are present in regions with volcanic bedrock. The economic situation in Kenya makes water supply inadequate as the Kenyan government lack resources to improve the accessibility for people. In places where people have access to safe and fresh water, i.e. from boreholes, many of them can’t afford to buy water from there.

By compiling borehole data from CDN´s archive and visualize it with a GIS –software a digitalized map was created. The map shows fluoride levels together with a.o. location, pH, conductivity and number of users. These parameters facilitate decisions on where forthcoming projects could be implemented. The possibility to extend the map with other parameters or borehole data is more or less unlimited. By creating this framework we hope to easier the work for CDN and to help them improve the water situation for the people in Nakuru and Baringo District. The map gives an overview about CDN´s previous work but it also gives them possibilities to look into future areas of interest. They are able to overlook the situation in a new way.

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

The conclusion of the field study in Baringo District is that people suffer because of the water situation. The area is arid and people are poor. During longer parts of the year the seasonal sources are dried out and people are forced to walk far distances to get water. The water in the permanent sources has, like Lake Baringo, high levels of fluoride and is very turbid. The quality in the seasonal sources is good with respect to fluoride levels but other aspects make the situation difficult. All water sources are used both by humans and cattle and the absence of good sanitation constitutes a severe risk of diseases being spread. Cholera and typhoid are two diseases present in the area from time to time. Also cleaning and washing takes place in or nearby the source which increases the risk of contamination. Information about location, condition and other parameters for each one of the 52 water sources has been put into the GIS – map as a spatial data layer. By using the map CDN are able to overview present situation in the area and decide where to put up the new treatment plant. Since Lake Baringo serve as the main water source during most part of the year a good position for the plant would be on the seashore in Kampi ya Samaki.

Figure 8.1 Jörgen with a water sample from Lake Baringo

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

9 RECOMMENDATIONS

After setting up the framework to the GIS-map over Nakuru and Baringo District from data received from the CDN we recommend:

• Use the map as a basis to easier the decision-making prior to water projects • Expand the amount of information about water issues in the GIS –map due to own requirements • Continue the field investigation to include also the east side of Lake Baringo. • Promote other students to carry on improving the water situation for the Kenyan people by GIS-mapping

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

10 REFERENCES

Literature Azizian F. (1993). Water treatment technology – Fluoride Removal (Activated Alumina).

Bregnhøj H. (1995). Processes and Kinetics of Defluoridation of Drinking Water Using Bone Char. Technical University of Denmark. ISBN 87-89220-26-9

Bulusu K.R. et al. (1979). Fluorides in Water, Defluoridation Methods and Their Limitations. Journal of the Institution of Engineers, vol 60, p 1-25.

CDN. Catholic Diocese of Nakuru Water Programme. Handout January 2005

Dean H.T. (1942). As Reproduced in "Health Effects of Ingested Fluoride" National Academy of Sciences, p 169, 1993

Deer W.A. et al. (1966). An introduction to the rock-forming minerals. Longman, corp. ISBN 0-582-44210-9

Fawell J.K. (2003). Fluoride in Drinking-water, Background document for development of WHO Guidelines for Drinking-Water Quality. World Health Organization, WHO 2004

Gaciri S.J. and Davies T.C (1993). The occurrence and geochemistry of fluoride in some natural waters of Kenya. Journal of Hydrology, no 143, p 395-412.

Gikunju J.K. et al. (1992). Fluoride levels in borehole water around Nairobi. Fluoride, vol 25, no 3, p 111-114.

Gikunju J.K. et al. (1995). Water Fluoride in the Molo Division of Nakuru District, Kenya. Fluoride, vol 28, no 1, p 17-20.

Gikunju J.K. et al (2002). River water fluoride in Kenya. Fluoride, vol 35, no 3, p 193- 196.

Manji F. et al. (1986). Dental Fluorosis in an Area of Kenya with 2 ppm Fluoride in the Drinking Water. Journal of Dental Research, vol 65, no 5, p 659-662.

Mariappan P. et al. (Unknown). Domestic Defluoridation Techniques and Sector Approach for Fluorosis Mitigation. Bharathidasan University of India.

Ministry of Finance and Planning (2002). Baringo District Development Plan 2002-2008. Effective Management for Sustainable Economic Growth and Poverty Reduction

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

Nanyaro J.T. et al. (1984). A geochemical model for the abnormal fluoride concentrations in waters in parts of northern Tanzania. Journal of African Earth Science, vol 2, no 2, p 129-140.

NEERI (1987) Defluoridation. Technology mission on drinking water in villages and related water management. National Environment Engineering Research Institute. Nagpur 440020, India

Nyaora Moturi W.K. et al. (2001). The contribution of drinking water towards dental fluorosis: A case study of Njoro Division, Nakuru District, Kenya. Environmental Geochemistry and Health, no 24, p 123-130, 2002

Phantumvanit P. et al. (1988) A Defluoridator for Individual Households. World Health Forum, vol 9, no 4, p 555-558.

Thylstrup A. and Fejerskov O. (1978). As Reproduced in "Health Effects of Ingested Fluoride". National Academy of Sciences, p 171, 1993

Personal Contacts

Jacobsen Peter, Technical Advisor, Water Quality Program, Catholic Diocese of Nakuru, Kenya. Personal Communication Jan – Mar 2005.

Salano Gertrude E., Projects Officer, Water Quality Program, Catholic Diocese of Nakuru, Kenya. Personal Communication Jan – Mar 2005.

Internet

Dicciani, N. (2003). Chemical & Engineering News. Fluorine URL: http://pubs.acs.org/cen/80th/fluorine.html (2005-02-08)

EBO, Encyclopædia Britannica Online (2005). Britannica Student Encyclopedia, Kenya URL: http://search.eb.com/ebi/article?tocId=9275253&query=kenya&ct= (2005-05-24)

FAN, Fluoride Action Network (2005). Excerpt from: CHEMICAL & ENGINEERING NEWS, August 1, 1988 Fluoridation of Water Questions about health risks and benefits remain after more than 40 years Bette Hileman, C&EN Washington URL: www.fluoridealert.org/s-fluorosis.htm (2005-05-10)

FAN, Fluoride Action Network (2005). HEALTH EFFECTS: Dental Fluorosis Classification Criteria URL: www.fluoridealert.org/health/teeth/fluorosis/criteria.html (2005-05-10)

Jörgen Näslund – Ingemar Snell GIS-mapping of Fluoride Contaminated Groundwater in Nakuru & Baringo district, Kenya A Minor Field Study

MDGs, Millennium Development Goals (2004). The World Bank Group, Middle East and North Africa (Goal 7) URL: http://developmentgoals.org (2005-03-14)

MoH, Ministry of Health, New Zealand (2005). Fluoridation in New Zealand URL: http://www.moh.govt.nz/moh.nsf/0/1374dc90e9a7ba1dcc256f42000d328f?OpenDocume nt (2005-04-26)

NE, Nationalencyklopedin (2005). Fluor URL: http://www.ne.se/jsp/search/article.jsp?i_art_id=171705 (2005-02-08)

UNICEF, United Nations Children’s Fund (2005). UNICEF's Position on Water Fluoridation, Water environment & sanitation, Fluoride in water: An overview URL: http://www.nofluoride.com/Unicef_fluor.htm (2005-05-26)

Jörgen Näslund – Ingemar Snell APPENDIX 1 Technical Data CDN Fluoride Filters

Typical Time size of Typical between Running No of Filter Type filter bed Consumtion Costs Regeneration service Costs Applications Bonechar + Regeneration [L] [L/Day] [KES] [Days] [KES/1000L] Household Filter 12 15 1 200 no 180 130 >600 Institutional Filter 450 300 40 000 no 270 130 12 Community Filter 2 500 2 500 300 000 yes 180 50 (30) 21 Waterworks Filters >20 000 200 000 1 500 000 yes 10 30 (10) 2

Bonechar + Contact Precipitation Household Filter 12 15 1 800 - 2 400 33 0 Institutional Filter 450 300 60 000 - 4 500 33 0 Community Filter 2 500 2 500 400 000 - 3 000 33 3

Jörgen Näslund – Ingemar Snell APPENDIX 2 Data Table; CDN boreholes, Nakuru

WELL-ID N/S E/W PROJ.NAME X Y PEOPLE DEPTH PH COND F D004 00 44' 20 36 29' 10 Mwega Nyakairu 36.4850 -0.7367 960 200 8,20 62 7,0 D007 00 41' 56 36 31' 45 Ngondi II 36.5242 -0.6927 5000 200 7,90 56 4,5 D008 00 43' 30 36 26' 37 Shindano Gituru 36.4395 -0.7217 5000 180 7,40 73 2,4 D009 00 43' 23 36 26' 26 Naivasha TC I 36.4377 -0.7205 5000 150 7,70 75 2,4 D011 00 45' 00 36 31' 12 Maraigushu 36.5187 -0.7500 0 250 8,10 71 1,0 D012 00 04' 30 36 29' 30 Nyamathi 36.4883 -0.0717 3600 247 7,60 24 2,2 D013 00 45' 48 36 31' 45 Karai I 36.5242 -0.7580 2400 210 8,30 73 9,6 D015 00 41' 25 36 28' 40 North Karati 36.4733 -0.6875 4160 160 8,70 55 6,4 D017 00 41' 30 36 27' 30 Nyondia 36.4550 -0.6883 2400 190 9,00 59 6,0 D018 00 39' 45 36 29' 00 New Karati 36.4833 -0.6575 8000 190 8,25 46 6,4 D022 00 47' 30 36 26' 30 D.N Handha 36.4383 -0.7883 1000 100 8,10 95 2,4 D023 00 45' 20 36 26' 50 Naivasha Sec. 36.4417 -0.7533 750 150 8,20 79 7,5 D024 00 46' 00 36 28' 26 Karai II 36.4710 -0.7667 3000 230 8,20 95 18,0 D025 00 57' 57 36 26' 50 Mirera II 36.4417 -0.9595 480 120 8,40 95 3,5 D026 00 16' 12 36 22' 01 OlKalou I 36.3668 -0.2687 300 150 7,60 31 1,3 D027 00 17' 47 36 10' 00 Karigi Ndege 36.1667 -0.2912 400 235 9,20 48 1,0 D028 00 06' 50 36 02' 40 Gichobo 36.0400 -0.1083 340 200 7,70 45 1,8 D029 00 29' 00 36 17' 40 St. Peters Prim. 36.2900 -0.4833 1950 120 6,00 24 1,9 D030 00 29' 00 36 17' 40 Murera Gilgil 36.2900 -0.4833 800 200 7,20 52 1,8 D033 Pastoral Centre 300 126 7,40 43 1,4 D034 00 03' 00 35 43' 00 Mercy Hospital 35.7167 -0.0500 1000 210 7,60 34 1,2 D035 00 22' 19 35 59' 58 Rare Kikapu 35.9930 -0.3698 400 195 8,30 32 4,5 D037 00 12' 40 35 42' 40 Franciscan Bro. 35.7067 -0.2067 300 155 7,60 16 1,6 D038 00 09' 30 36 11' 40 Koiyo Kamosop 36.1900 -0.1550 1000 135 7,90 18 0,2 D040 00 02' 03 36 32' 04 Rumuruti Missio 36.5340 0.0338 300 200 9,30 70 2,0 D059 00 54' 03 36 06' 10 Mary Mt. sec. 36.1017 -0.9005 300 205 7,50 21 1,6 D060 00 54' 03 36 06' 13 MoloTown Sec. 36.1022 -0.9005 300 130 7,50 17 1,0 D061 00 53' 57 36 05' 46 Kapkelek 36.0910 -0.8928 250 200 7,50 30 1,2 D062 00 54' 11 36 05' 34 Nyonjoro 36.0890 -0.9018 1615 87 6,40 56 4,0 D063 00 20' 00 35 06' 80 Njoro parish 35.1133 -0.3333 2100 197 7,00 31 1,8 D065 00 11' 45 36 32' 58 Gatundia 36.5430 -0.1908 1450 165 8,30 54 1,2 D066 00 04' 00 36 27' 00 Pondo 36.4500 -0.0667 1460 105 9,10 61 1,6 D067 00 02' 00 36 27' 30 Mutanga 36.4550 -0.0333 1500 80 7,30 39 1,4

1 Jörgen Näslund – Ingemar Snell APPENDIX 2 Data Table; CDN boreholes, Nakuru

D068 00 53' 42 36 06' 04 Moiben Township 36.1007 0.8903 1500 80 8,80 74 10,0 D070 01 51' 41 36 03' 12 Lokori 2 36.0520 1.8568 800 20 7,90 9 1,1 D072 02 23' 01 35 38' 46 Lokichar 35.6410 2.3835 700 60 7,70 64 0,3 D075 00 16' 54 36 08' 34 Kiamunyeki 36.1390 -0.2757 1800 120 8,10 50 1,4 D076 00 19' 30 36 27' 00 Ndemi 36.4500 -0.3217 2000 85 8,20 38 1,4 D077 00 02' 53 36 25' 15 Aiyam 36.4192 -0.0422 1600 170 8,20 67 2,2 D078 Chomu 1700 160 8,50 70 1,4 D079 00 17' 40 36 08' 03 Lanet-CDN 36.1338 -0.2900 1200 130 7,50 43 2,0 D080 00 10' 50 35 59' 28 Ol Rongai 35.9880 -0.1750 1800 270 7,00 68 11,0 D081 00 54' 09 36 05' 35 Corner 36.0892 -0.9015 2000 180 8,10 64 8,0 D082 00 30' 20 36 27' 24 Gathengera 36.4540 -0.5033 2000 240 7,70 57 7,5 D083 00 47' 36 36 31' 58 Kiu 36.5263 -0.7893 1900 100 8,20 122 9,6 D084 00 54' 08 36 05' 35 Good Faith 36.0892 -0.9013 1800 200 6,70 120 2,5 D085 01 13' 50 35 45' 40 Lomelo Mission 35.7567 1.2250 400 50 8,00 640 0,1 D087 00 28' 23 36 55' 30 Wamagana 36.9217 -0.4705 300 130 6,60 33 2,0 D090 00 54' 09 36 05' 35 St. James Kirima 36.0892 -0.9015 800 200 8,40 36 2,0 D092 00 04' 57 36 13' 30 St. Francis Sec. 36.2217 -0.0762 600 110 6,80 18 2,0 D093 St. Mary Matundura 7000 182 8,40 32 2,5 D094 00 33' 57 36 36' 21 Sosian Scheme 36.6035 0.6095 800 150 8,50 58 0,8 D097 Tangulbei commun 950 110 8,10 74 2,5 D099 Luyeya 870 95 8,30 179 6,9 D102 00 16' 52 36 07' 05 St. Peter Lanet 36.1175 -0.2753 1600 95 7,10 42 2,8 D103 00 20' 24 35 58' 02 Egerton ll 35.9670 -0.3373 2480 180 7,20 26 2,0 D104 00 23' 40 35 57' 58 Mutaro 35.9597 -0.3900 1500 140 8,30 40 6,0 D109 00 02' 15 37 02' 00 Nkabune Sisters 37.0333 -0.0358 800 100 6,80 160 D110 00 47' 02 34 04' 28 Rakwaro 34.0713 -0.7837 400 80 6,30 16 0,6 D117 01 19' 43 36 37' 47 Morijo 36.6245 1.3238 920 146 8,50 54 1,0 D119 00 09' 36 35 51' 45 Arasa 35.8575 -0.1560 100 70 8,60 62 4,3 D121 00 21' 40 35 59' 30 Umoja 35.9883 -0.3567 1200 102 6,80 40 4,0 D122 00 41' 20 35 44' 03 Molo Academy 35.7338 -0.6867 800 125 7,00 20 1,0 D123 00 17' 47 35 47' 57 Elburgon Industrie 35.7928 -0.2912 1200 140 6,80 20 1,0 D129 00 20' 54 37 34' 55 Isiolo C. Mission 37.5758 0.3423 300 70 7,00 140 0,2 D130 00 24' 56 37 35' 58 Isiolo Nomad (Gaba 37.5930 0.4093 600 55 7,10 98 0,2 D131 02 20' 20 37 34' 30 Isiolo Seminary 37.5717 2.3367 300 70 7,00 85 0,4 D133 00 42' 15 36 26' 47 Naivasha Prison 36.4412 -0.7025 300 105 7,86 58 15,0

2 Jörgen Näslund – Ingemar Snell APPENDIX 2 Data Table; CDN boreholes, Nakuru

D135 00 29' 37 34 17' 22 Kanyauke 34.2870 -0.4895 370 70 7,40 110 3,0 D137 00 47' 41 36 25' 51 Kigome 36.4252 -0.7902 200 110 8,80 36 5,5 D139 00 16' 12 36 32' 13 Rumuruti Mission 36.5355 0.2687 400 110 9,30 72 4,6 D140 00 20' 52 36 22' 43 Sipili 36.3738 0.3420 800 200 8,50 66 0,2 D142 01 06' 45 34 22' 45 Saggia 36.3742 -1.1075 300 51 7,80 32 1,0 D143 00 10' 15 36 21' 00 Elite school II 36.3500 -0.1692 600 120 6,60 8 0,2 D144 00 22' 47 34 31' 40 Wandigi 34.5233 -0.3745 1240 80 8,40 82 2,8 D146 00 26' 19 37 40' 00 Chumvieri 37.6667 0.4365 400 60 6,90 80 0,1 D147 00 16' 41 36 09' 30 Tuinuane 36.1550 -0.2735 1090 145 8,00 49 3,8 D148 00 41' 50 36 05' 10 Komolion community 36.0850 0.6917 1560 25 8,40 170 3,0 D149 00 41' 50 36 05' 10 Komolion dispensar 36.0850 0.6917 680 20 7,70 88 3,1 D150 00 30' 50 36 25' 00 Nyalilpich 36.4167 0.5083 1210 90 7,70 72 1,0 D151 00 40' 43 37 31' 00 Kangeta 37.5167 -0.6738 1260 75 7,10 160 0,9 D154 00 47' 20 37 33' 42 Makima 37.5570 -0.7867 850 60 7,00 170 1,1 D155 00 29' 25 37 28' 16 Bishop's hse(Embu) 37.4693 -0.4875 400 110 7,80 28 1,0 D156 00 58' 05 37 27' 28 Dev. Office Embu 37.4547 -0.9675 300 100 8,40 80 9,0 D157 00 48' 23 37 24' 15 Kitololoni 37.4025 -0.8038 890 110 7,10 130 2,5 D158 00 42' 50 37 39' 45 Iriamurai Embu 37.6575 -0.7083 780 125 6,05 150 3,8 D159 00 36' 30 35 56' 25 Koroto 35.9375 0.6050 1200 60 7,80 88 0,2 D163 00 32' 44 37 34' 57 Riandu Embu 37.5762 -0.5407 800 90 6,95 28 0,3 D168 00 34' 57 37 38' 40 Siakago Sec. Schoo 37.6400 -0.5762 840 120 7,30 84 0,4 D169 00 50' 00 34 11' 40 Andreas Manna 34.1900 -0.8333 340 140 8,30 98 0,6 D170 00 40' 30 37 36' 25 Nyangwa 37.6042 -0.6717 900 80 7,00 84 0,9 D171 01 21' 49 38 00' 39 Kitui Pastrol Cent 38.0065 -1.3582 500 120 6,90 44 0,2 D172 00 33' 58 35 08' 09 Cheborge 35.1348 -0.5597 860 100 8,10 32 1,9 D174 00 26' 00 35 41' 00 Keringet 35.6833 -0.4333 850 95 6,80 16 0,4 D175 00 24' 48 36 55' 26 Dev.Office Nyeri 36.9210 -0.4080 500 110 7,40 110 0,3 D176 00 02' 45 36 28' 42 Kihingo Dispensary 36.4737 0.0408 1200 165 8,30 31 0,3 D177 00 01' 43 36 17' 32 Igwamiti 36.2887 0.0238 1050 150 7,00 49 7,1 D178 00 05' 49 36 07' 42 Solai Secondary 36.1237 -0.0915 600 130 7,30 39 1,0 D180 00 35' 00 36 29' 30 Murungaru 36.4883 -0.5833 1650 160 8,50 45 5,1 D181 00 23' 42 36 32' 22 Machunguru 36.5370 -0.3903 1250 180 8,80 83 2,0 D183 Poro 1000 62 7,70 20 0,2 D184 00 46' 50 36 31' 40 Longewan 36.5233 0.7750 1500 230 8,60 63 1,6 D186 00 20' 25 35 41' 30 Simon Ngure 35.6883 -0.3375 400 105 7,10 17 2,7

3 Jörgen Näslund – Ingemar Snell APPENDIX 2 Data Table; CDN boreholes, Nakuru

D187 00 50' 45 36 07' 50 Matunda 36.1250 0.8408 960 67 8,00 44 0,9 D188 Milimani 700 135 8,10 48 5,2 D189 00 50' 29 37 22' 57 Naisunyai 37.3762 0.8382 600 80 8,40 141 2,4 D192 00 26' 12 36 40' 47 Sosian 36.6745 0.4353 1100 130 8,60 132 4,6 D193 Karson Flowers 200 8,80 81 3,6 D194 00 46' 36 36 32' 18 Nyakairu 36.5363 -0.7727 208 8,00 34 4,2 D195 00 17' 30 36 24' 15 Khirrecu 36.4025 0.2883 7,60 46 3,7 D196 00 19' 45 35 58' 50 Gota Phares (Sunse 35.9750 -0.3242 140 7,00 19 1,8 D199 Rumwe Elburgon 170 7,00 30 1,5 D200 00 34' 48 37 29' 39 Don Bosco Girls 37.4898 -0.5747 90 8,87 60 3,0 D201 00 42' 15 36 29' 45 Naivasha East 36.4908 -0.7025 190 7,90 56 7,5 D203 00 45' 11 37 30' 50 Mashamba 37.5083 -0.7518 80 7,40 127 1,1 D204 00 48' 09 37 31' 09 Mbondoni 37.5182 -0.8015 80 7,10 174 1,0 D207 Nyonjoro 106 8,10 50 2,7 D208 01 13' 38 36 06' 40 Natan 36.1067 1.2230 70 8,40 364 21,3 D209 00 24' 50 36 15' 15 Srs. of Sacred Hea 36.2525 -0.4083 140 7,90 75 6,2 D210 01 07' 55 36 37' 26 Lpartuk 36.6210 1.1258 121 7,20 42 1,0 D214 00 14' 28 36 07' 28 St. Anthony Acade. 36.1213 -0.2380 130 8,20 58 6,4 D215 00 02' 00 34 10' 42 Rayudhi 34.1737 -0.0333 90 7,10 540 2,9 D217 00 49' 55 34 17' 02 Osani 34.2837 -0.8258 80 8,80 70 1,0 D218 00 31' 03 34 17' 05 Olweya 34.2842 -0.5172 150 9,00 65 7,2 D219 00 45' 09 36 11' 56 Kijabe Ltd. Ndabib 36.1927 -0.7515 185 7,80 37 6,9 D220 00 09' 30 36 07' 50 Jomo Kenyatta Sch 36.1250 -0.1550 1000 220 8,30 32 2,3 D222 00 35' 00 34 13' 40 Suba Water Project 34.2233 -0.5833 100 7,50 80 1,0 D223 Kijabe Ltd. Ndabib 105 8,30 40 6,9 D224 Kijabe Ltd. Ndabib 120 7,90 40 8,3 D225 Kijabe Ltd. 4 65 7,10 79 4,2 D226 Kijabe Ltd. 5 70 7,80 109 6,6 D227 02 00' 32 38 58' 00 ICRC-Basir-Wajir 38.9667 2.0053 120 7,60 107 1,2 D228 02 04' 00 39 11' 00 ICRC-Garse Koftu 39.1833 2.0667 54 7,90 131 1,1 D229 01 17' 00 39 45' 00 ICRC-Arthi Bohol 39.7500 1.2833 105 8,00 272 1,4 D231 Kijabe Ltd. 6 50 7,60 64 4,2 D232 01 48' 30 35 42' 45 Ilkerin-Loita IDP 35.7075 -1.8050 130 7,30 102 1,9 D233 00 20' 45 36 03' 45 Bishop Ndingi Aca. 36.0575 -0.3408 54 8,40 78 13,2 D234 00 17' 26 36 47' 18 St. Clare School 36.7863 -0.2877 150 8,10 26 0,6

4 Jörgen Näslund – Ingemar Snell APPENDIX 2 Data Table; CDN boreholes, Nakuru

D235 00 33' 15 36 08' 15 Kiptangwanyi 36.1358 -0.5525 250 7,90 39 6,0 D237 00 25' 08 35 58' 31 Sinendet Water Pro 35.9718 -0.4180 140 7,40 58 5,4 D238 00 42' 56 34 45' 03 Misikhu Hospital 34.7505 0.7093 86 6,20 26 0,2 D241 00 26' 15 36 01' 10 St. Francis Lare 36.0183 -0.4358 205 7,80 43 4,4 D242 00 10' 40 35 52' 42 Mama Ngina Kenya. 35.8737 -0.1733 130 7,50 44 6,0 D243 00 28' 15 36 03' 45 Kilo Primary Schoo 36.0575 -0.4692 75 7,10 23 1,4 D247 00 33' 17 36 58' 55 Witima Water Proj. 36.9758 -0.5528 175 6,80 36 0,1 D248 Pivot Hotel 100 8,60 430 23,2 D249 00 11' 45 35 37' 45 Mercy Girls Sch. 35.6242 -0.1908 120 8,70 81 3,6 D250 01 00' 42 36 46' 58 Lier Village 36.7763 1.0070 78 8,10 76 0,5 D251 00 17' 27 36 04' 20 Bishop's House 36.0700 -0.2878 120 9,20 320 40,0 D253 00 33' 20 34 16' 33 Matunga Site 34.2722 -0.5533 100 7,20 102 1,5 D255 00 33' 25 34 36' 07 Ruma Pap Site 34.6012 -0.5542 100 7,60 103 4,6 D256 00 30' 59 34 15' 10 Nyabera II 34.2517 -0.5098 120 8,00 69 1,0 D257 00 34' 07 34 14' 23 Victor Musoga Site 34.2372 -0.5678 55 7,90 80 1,0 D260 00 19' 30 35 56' 15 Njoro Special Sch. 35.9358 -0.3217 180 7,20 31 2,1 D269 00 20' 35 34 16' 30 Kamarowa B' 34.2717 -0.3392 75 7,40 113 2,0 D270 00 30' 35 34 18' 12 Kamreri II 34.3020 -0.5058 80 7,40 148 1,7 D271 00 32' 47 34 32' 02 Ajwang 34.5337 -0.5412 70 7,10 92 1,7 D273 00 06' 15 36 09' 45 Berea Theological 36.1575 -0.1025 65 7,40 29 0,5 D277 01 04' 18 34 28' 23 Rayudhi 'B' 34.4705 -1.0697 80 7,90 88 1,3 D280 00 48' 25 34 18' 52 Wachara 'K' 34.3087 -0.8042 60 8,60 67 1,2 D281 00 16' 16 36 03' 43 Comply Industries 36.0572 -0.2693 156 8,40 180 18,6 D282 00 12' 30 36 07' 30 Dr. Kelvin Kariuki 36.1217 -0.2050 150 7,70 30 2,3 D283 00 29' 30 36 29' 30 Alice M. Ng'ang'a 36.4883 -0.4883 200 8,20 50 7,2 D284 00 19' 49 35 58' 46 Egerton W. H. C. 35.9743 -0.3248 160 7,30 26 2,8 D285 00 02' 45 36 14' 30 Kasambara Hospital 36.2383 -0.0408 150 6,90 36 2,9 D286 00 16' 45 36 04' 45 Sikh Temple 36.0742 -0.2742 1000 95 8,70 150 12,0 D287 00 24' 50 36 15' 15 Poor Servants 36.2525 -0.4083 140 8,50 99 9,3 D288 00 00' 25 36 23' 06 Catholic Tabor Hil 36.3843 -0.0042 140 6,80 17 0,3 D294 00 33' 24 34 34' 24 Mwirendia Communi. 34.5707 -0.5540 80 7,20 80 1,2 D301 00 00' 00 36 22' 05 Equator Catholic 36.3675 0.0000 122 7,10 14 0,3 D302 00 16' 15 36 21' 31 Muhotetu Church 36.3552 -0.2692 120 7,40 58 0,7 D304 00 03' 55 34 12' 45 Usenge water proje 34.2075 0.0592 60 7,20 180 0,4 D305 00 41' 15 35 46' 30 Matumaini 35.7717 -0.6858 110 7,10 39 0,7

5 Jörgen Näslund – Ingemar Snell APPENDIX 2 Data Table; CDN boreholes, Nakuru

D307 00 18' 30 36 05' 30 Miondwe Enterprise 36.0883 -0.3050 160 8,70 52 11,1 D309 02 10' 49 37 48' 30 Parakishon 37.8050 2.1748 85 7,70 91 0,1 D314 00 19' 40 34 30' 20 Cornell Anguche 34.5033 0.3233 70 6,10 14 0,2 D319 00 53' 33 34 55' 24 Nicholas O. Mariit 34.9207 0.8888 70 7,00 15 0,3 D320 00 40' 53 34 42' 13 Namawanga 34.7022 0.6755 65 7,00 19 0,1 D322 00 38' 03 35 52' 03 Suitechun 35.8672 0.6338 500 110 7,40 114 1,4 D323 00 42' 06 36 01' 28 Kiplelchiony 36.0213 0.7010 500 95 8,90 147 17,0 D324 00 43' 38 36 56' 42 Ngaratuko 36.9403 0.7230 600 79 6,90 81 0,5 D326 00 40' 26 35 57' 48 Naiben 35.9580 0.6710 1000 112 7,90 75 0,5 D327 00 40' 37 35 52' 07 Biretuonin 35.8678 0.6728 1400 52 7,30 83 2,4 D328 00 34' 48 35 56' 11 Chebarsiat 35.9352 0.5747 600 106 7,60 91 0,5 D333 Chemeril 3000 94 7,10 65 4,5 D334 Sosionde 85 8,60 100 0,6 D335 Katilomwo 250 85 8,30 46 1,0 D336 Nalekat 750 87 7,10 350 0,3 D338 00 32' 01 34 32' 11 Bungoma Bible Sch 34.5352 0.5335 42 7,50 25 0,6 D339 RVP Police Dog Uni 135 7,70 44 4,7 D342 Francis Muchemi M. 7,30 30 2,0 D344 Marula Estates 1 70 7,70 57 5,9 D352 St. Timothy Parish 120 7,60 23 1,9 D355 Kailer BTC Baringo 8,50 284 12,0 D358 Daniel Ikanyi 123 7,70 18 0,8

6 Jörgen Näslund – Ingemar Snell APPENDIX 3 Borehole ID and Fluoride Level from CDN files, Nakuru

Level < 1,5 mg F/L D011 1 D122 1 D175 0,3 D256 1 D335 1 D026 1,3 D123 1 D176 0,3 D257 1 D336 0,3 D027 1 D129 0,2 D178 1 D273 0,5 D338 0,6 D033 1,4 D130 0,2 D183 0,2 D277 1,3 D358 0,8 D034 1,2 D131 0,4 D187 0,9 D280 1,2 D038 <0,2 D140 0,2 D199 1,5 D288 0,3 D060 1 D142 1 D203 1,1 D294 1,2 D061 1,2 D143 0,2 D204 1 D301 0,3 D065 1,2 D146 0,1 D210 1 D302 0,7 D067 1,4 D150 1 D217 1 D304 0,4

D070 1,1 D151 0,9 D222 1 D305 0,7 D072 0,3 D154 1,1 D227 1,2 D309 0,1 D075 1,4 D155 1 D228 1,1 D314 0,2 D076 1,4 D159 0,2 D229 1,4 D319 0,3 D078 1,4 D163 0,3 D234 0,6 D320 0,1 D085 0,1 D168 0,4 D238 0,2 D322 1,4 D094 0,8 D169 0,6 D243 1,4 D324 0,5 D109 nil D170 0,9 D247 0,1 D326 0,5 D110 0,6 D171 0,2 D250 0,5 D328 0,5 TOTAL 84 D117 1 D174 0,4 D253 1,5 D334 0,6

Level 1,5 - 3,0 mg F/L D008 2,4 D063 1,8 D102 2,8 D189 2,4 D271 1,7 D009 2,4 D066 1,6 D103 2 D196 1,8 D282 2,3 D012 2,2 D077 2,2 D135 3 D200 3 D284 2,8 D022 2,4 D079 2 D144 2,8 D207 2,7 D285 2,9 D028 1,8 D084 2,5 D148 3 D215 2,9 D327 2,4 D029 1,9 D087 2 D157 2,5 D220 2,3 D342 2 D030 1,8 D090 2 D172 1,9 D232 1,9 D352 1,9 D037 1,6 D092 2 D181 2 D260 2,1 D040 2 D093 2,5 D184 1,6 D269 2 TOTAL 47 D059 1,6 D097 2,5 D186 2,7 D270 1,7

1 Jörgen Näslund – Ingemar Snell APPENDIX 3 Borehole ID and Fluoride Level from CDN files, Nakuru

Level 3,0 - 10,0 mg F/L D004 7 D068 10 D147 3,8 D195 3,7 D231 4,2 D007 4,5 D081 8 D149 3,1 D201 7,5 D235 6 D013 9,6 D082 7,5 D156 9 D209 6,2 D237 5,4 D015 6,4 D083 9,6 D158 3,8 D214 6,4 D241 4,4 D017 6 D099 6,9 D177 7,1 D218 7,2 D242 6 D018 6,4 D104 6 D180 5,1 D219 6,9 D249 3,6 D023 7,5 D119 4,3 D188 5,2 D223 6,9 D255 4,6 D025 3,5 D121 4 D192 4,6 D224 8,3 D283 7,2 D035 4,5 D137 5,5 D193 3,6 D225 4,2 D287 9,3 D062 4 D139 4,6 D194 4,2 D226 6,6 D333 4,5

D339 4,7 D344 5,9

TOTAL 52

Level >10,0 mg F/L D024 18 D323 17 D080 11 D355 12 D133 15 D208 21,3 D233 13,2 TOTAL 12 D248 23,2 D251 40 D281 18,6 D286 12 D307 11,1

2 Jörgen Näslund – Ingemar Snell APPENDIX 4 Application in ArcView 3.2 – CDN boreholes, Kenya

Jörgen Näslund – Ingemar Snell APPENDIX 5 Data table; Water Sources, Lake Baringo area

SOURSE NO. OF NAME N/S E/W DATE NOTE F PH COND TURB SS TYPE CONSTR. DURABILITY USERS X Y River 1 00 36' 495 36 00' 967 Seasonal Natural 36,0161 0,6083 River 2 00 36' 329 36 00' 681 Seasonal Natural 36,0114 0,6055 Pound 1 00 36' 272 36 00' 211 Seasonal Natural 1500 36,0035 0,6045 River 3 00 35' 998 36 00' 234 Seasonal Natural 36,0039 0,6000 River 4 00 34' 607 35 59' 825 Seasonal Natural 35,9971 0,5768 River 5 00 34' 956 35 59' 470 2005-03-21 Sample 0.37 6.95 30 48 < 0.05 Permanent Pot 35,9912 0,5826 CCF Borehole 00 32' 820 35 59' 296 2005-03-21 Sample 0.90 7.84 64 1 < 0.05 Permanent Borehole 35,9883 0,5470 River 6 00 33' 340 35 59' 492 Seasonal Natural 35,9915 0,5557 River 7 00 33' 607 35 59' 506 Seasonal Natural 35,9918 0,5601 CCF Tap 2 00 33' 762 35 59' 489 2005-03-21 Sample 0.96 7.52 64 1 < 0.05 Permanent Tap 35,9915 0,5627 River 8 00 34' 245 35 59' 571 2005-03-21 Sample 0.50 7.46 21 269 42.00 Seasonal Natural 35,9929 0,5708 Pound 2 00 34' 763 35 59' 840 Seasonal Natural 35,9973 0,5789 Pound 3 00 35' 334 35 59' 953 Seasonal Natural 35,9992 0,5889 River 9 00 35' 899 36 00' 451 Seasonal Natural 36,0075 0,5983 Shallow well 1 00 35' 763 36 00' 422 2005-03-22 Sample 2.86 7.46 78 27 < 0.05 Permanent Manmade 120 36,0070 0,5961 River 10 00 35' 805 36 00' 612 2005-03-22 Sample 1.69 7.84 52 66 < 0.05 Seasonal Natural 36,0102 0,5968 River 11 00 35' 189 36 00' 776 Seasonal Natural 36,0129 0,5865 River 12 00 35' 266 36 00' 795 Seasonal Pot 2 weeks 36,0133 0,5878 River 13 00 34' 888 36 01' 112 Seasonal Natural 36,0185 0,5815 Pound 4 00 34' 506 36 01' 868 2005-03-22 Sample 0.37 7.31 20 191 40.00 Seasonal Manmade 6 months 700 36,0311 0,5751 River 14 00 35' 286 36 01' 540 Seasonal Natural 100 36,0257 0,5881 River 15 00 35' 352 36 01' 491 Seasonal Natural 36,0249 0,5892 River 16 00 34' 868 36 00' 315 2005-03-22 Sample 0.26 7.17 12 41 < 0.05 Seasonal Natural 36,0053 0,5811 Pound 5 00 34' 678 35 59' 948 Seasonal Natural 4 months 500 35,9991 0,5780 River 17 00 34' 611 35 59' 968 2005-03-22 Sample 1.81 7.44 35 63 < 0.05 Seasonal Natural 35,9995 0,5769 River 18 00 32' 121 35 59' 566 Seasonal Natural 35,9926 0,5354 Kampi ya Samaki 00 37' 219 36 01' 775 2005-03-22 Sample 5.36 8.73 128 5 < 0.05 Permanent Manmade 300 36,0296 0,6203 Shallow well 2 00 40' 683 36 00' 622 Seasonal Natural 8 months 500 36,0104 0,6781 Pound 6 00 40' 660 36 00' 674 Seasonal Natural 3 months 36,0112 0,6777 Pound 7 00 40' 935 36 00' 710 Seasonal Manmade 1 months 36,0118 0,6823 Shallow well 3 00 40' 767 36 00' 892 2005-03-23 Sample 0.13 7.24 8 37 < 0.05 Seasonal Pot 40 36,0149 0,6795 Pound 8 00 40' 753 36 01' 296 2005-03-23 Sample 0.46 7.20 8 182 < 0.05 Seasonal Manmade 3 months 36,0216 0,6792

1 Jörgen Näslund – Ingemar Snell APPENDIX 5 Data table; Water Sources, Lake Baringo area

Pound 9 00 41' 800 36 01' 352 2005-03-23 Sample 0.35 7.24 6 159 < 0.05 Seasonal Manmade 400 36,0225 0,6967 River 19 00 41' 026 36 01' 536 Seasonal Natural 36,0256 0,6838 Lake Baringo 00 40' 839 36 01' 859 2005-03-23 Sample 7.16 8.72 85 163 < 0.05 Permanent Natural 36,0310 0,6807 River 20 00 40' 038 36 00' 885 2005-03-23 Sample 0.28 7.30 8 157 < 0.05 Seasonal Natural 200 36,0148 0,6673 River 21 00 39' 782 36 00' 809 2005-03-23 Sample 0.27 6.86 12 78 < 0.05 Seasonal Natural 180 36,0135 0,6630 Pound 10 00 40' 348 36 01' 205 2005-03-23 Sample 0.45 7.11 5 217 < 0.05 Seasonal Manmade 6 months 90 36,0201 0,6725 Pound 11 00 39' 829 36 01' 105 2005-03-23 Sample 0.35 7.02 6 188 < 0.05 Seasonal Natural 36,0184 0,6638 River 22 00 37' 058 36 01' 316 Seasonal Natural 1 week 36,0219 0,6176 River 23 00 36' 908 36 01' 195 Seasonal Natural 1 week 36,0199 0,6151 Pound 12 00 36' 729 36 01' 202 Seasonal Manmade 1 months 300 36,0200 0,6122 River 24 00 36' 584 36 00' 918 Seasonal Natural 8 months 700 36,0153 0,6097 River 25 00 36' 637 36 00' 704 Seasonal Dam 2 weeks 100 36,0117 0,6106 River 26 00 36' 777 36 00' 541 Seasonal Natural 2 weeks 200 36,0090 0,6130 Pound 13 00 36' 871 36 00' 731 Seasonal Dam 3 weeks 36,0122 0,6145 Pound 14 00 36' 976 36 00' 791 Seasonal Dam 36,0132 0,6163 Pound 15 00 37' 116 36 00' 958 Seasonal Dam 2 weeks 200 36,0160 0,6186 Pound 16 00 37' 252 36 01' 338 Seasonal Dam 2 weeks 500 36,0223 0,6209 River 27 00 37' 038 36 01' 497 Seasonal Dam 36,0250 0,6173 Pound 17 00 42' 464 36 01' 620 2005-03-24 Sample 2.06 7.05 14 219 < 0.05 Seasonal Manmade 1 months 500 36,0270 0,7077 Pound 18 00 44' 564 36 01' 851 2005-03-24 Sample 1.60 7.29 14 106 < 0.05 Permanent Manmade 1500 36,0309 0,7427

2 Jörgen Näslund – Ingemar Snell APPENDIX 6 Water Source ID and Fluoride Level, Lake Baringo area

Level < 1,5 mg F/L Level 1,5 - 3,0 mg F/L Level 3,0 - 10,0 mg F/L River 5 0,37 CCF 2 0,96 River 10 1,69 Lake Baringo 7,16 River 8 0,5 CCF Tap 3 0,89 River 17 1,81 Kampi ya Samaki 5,36 River 16 0,26 Shallow well 3 0,13 Pound 17 2,06 River 20 0,28 Pound 9 0,35 Pound 18 1,6 River 21 0,27 Shallow well 1 2,86 Pound 4 0,37 Pound 8 0,46 Pound 10 0,45 TOTAL 14 TOTAL 5 TOTAL 2 Pound 11 0,35 CCF 0,9

Jörgen Näslund – Ingemar Snell APPENDIX 7 Application in ArcView 3.2 – Lake Baringo area

Jörgen Näslund – Ingemar Snell