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Home , Bank (geography), Downcutting, Mountain stream, Stream, Stream bed

U.S. & Service Visual Assessment Manual

Cane , credit USFWS/Gary Peeples U.S. Fish & Wildlife Service

Conasauga River, credit USFWS Table of Contents Introduction...... 1

What is a Stream?...... 1

What Makes a Stream “Healthy”?...... 1

Pollution Types and How Pollutants are Harmful...... 1

What is a “Reach”?...... 1

Using This Protocol...... 2

Reach Identification...... 2

Context for Use of this Guide...... 2

Assessment...... 3

Scoring Details...... 4

Channel Conditions...... 4

Riparian Zone...... 5

Bank Stability...... 6

Water Appearance...... 7

Nutrient Enrichment...... 8

Macroinvertebrate ...... 9

Hydrologic alterations...... 12

Glossary...... 13 U.S. Fish & Wildlife Service

What is a Stream? signify that there are likely a good Introduction A “stream” is created when water that many smaller pollutants dissolved This guide should help a casual stream flows from a higher surface begins to run in the water (check out “How downhill, joining with other overflowing Pollutants Harm Water Quality/ visitor both recognize and evaluate the water trickles to form bodies of water. The Science Behind Pollutants” for factors that affect a stream to interpret The source of the water is typically details). , melted , or water flowing the overall health of a stream, and the underground, near the surface. This n Living Organisms – The types of collection of water moves with gravity things that live in it! living creatures present can tell you as it flows downward, often joining other how healthy the water is. When the to form larger bodies of water, presence of something indicates the which often eventually flow into final aquatic destinations like or . health of its environment, it is called a biological indicator. n Nearby Influences – Streams are negatively affected by runoff and pollution from the surrounding watershed. Sources of runoff can be busy city streets, waste from neighborhoods or local shopping centers, or pet waste/manure from animal farms. Pollution Types and How Pollutants are Harmful A pollutant is anything that enters a water source and makes it impure or less safe to drink or use. There are two broad categories of types of pollution: Point source pollution and nonpoint source pollution. Deep River, credit USFWS A stream interacts with the environment it winds through, bumping against rocks, n Point source pollution comes from tree roots, and natural and manmade an identifiable source, such as a structures. These interactions affect the factory pipe dumping waste directly stream’s DNA, like its size, flow speed, into a stream, or runoff from an dirt level, what lives in the stream, etc. animal farm nearby. These interactions ultimately determine a stream’s health! n Nonpoint source pollution means that the origin of the pollutant What Makes a Stream “Healthy”? is unknown. Examples of this Many biological, physical, and chemical include food packages, cigarettes, processes interact in one stream. Since pesticides, grease, and other waste everything in the stream ecosystem is that litters the ground and can interconnected, any change to a factor harm water quality. of a stream—like the amount of or rainfall in the stream—can impact other What is a “Reach”? factors. When using this guide, you will be judging overall stream health based A healthy stream will look and function on the section of the stream you will differently depending on where it is in the be evaluating, which is referred to as country and the landscape. For example, the stream reach. A reach is simply a a stream will be cooler and segment of a that does a good flow faster than a stream near the coast. job representing what the rest of the However, there are several key things to waterway looks like. Choosing a good look for when judging the health of any reach is important because the scores you stream, regardless of where it is located: give your stream will be based entirely off what you observe within it. Be sure n Trash, oil, or other visible to choose a reach of at least about 30 pollutants – These are a dead feet (around 10 meters) that includes giveaway that a stream might be in the elements seen along the rest of the trouble. Bigger, visible pollutants stream. 1 U.S. Fish & Wildlife Service

The Stream Visual Assessment Protocol what you find there is also encouraged Using This Protocol is intended to be a simple, detailed guide to help you keep good records and share that assesses the condition of a stream what you find with others. Context for in an easy-to-use way. It is suitable as a basic first estimate of stream condition. The active width can be Use of this Guide It can also be used to identify the need for determined by finding the place along more accurate assessment methods that your reach where it appears the stream is focus on a particular aspect of the aquatic at its widest when it is the most full. You system. can tell the maximum “flooding level” of a stream by looking at where the The SVAP should be usable nationwide. seems to hang over the stream, there Though regional differences matter when is , or there is very little green grading a stream, this assessment has . been designed to measure factors that are the least sensitive to regional differences. Note that at the time you use this guide to grade a stream, the stream may not Assessment be at its highest water level. For this The overall assessment score is protocol, a visual estimate of the average determined by adding the values for each channel width is good enough. For the element, and dividing by the number of “assessment scores” section, assign a elements scored. For example, if your value for each of the seven elements scores add up to 76 and you assessed 12 based on your best judgment. If any elements, then the overall assessment element is not relevant to your site, value would be 6.3 (76 divided by 12 then do not score that section at all. Any equals 6.3). This value can then be used elements omitted will not be included in to make general statements about the the “overall assessment” calculation. environmental condition in and around the stream, and, if used more than once, Scoring Details can show how a stream changes over The following instructions will help you time. understand how to grade characteristics of the stream. All of the following Reach Identification characteristics include detailed items to This section asks you to record basic info look for that can tell you if the stream about the reach, including name, location, is in good, moderate, or poor condition. and surrounding land uses. Space is After reading each section, use the given provided for drawing a picture of the scale to give that characteristic a score reach, which may be useful for revisiting on your sheet that will be added up for a the site, or for pointing out problem final score. areas. Taking pictures of the reach and

East Fork Headwaters, USFWS/Gary Peeples 2 U.S. Fish & Wildlife Service

Fish and Wildlife Service Visual Assessment Manual

Evaluator Name______

Date______

Stream Name______

Assessment Scores (1-10) Channel Conditions ______

Riparian Zone ______

Bank Stability ______

Water Appearance ______

Nutrient Enrichment ______

Macroinvertebrate habitat ______

Hydrologic alterations ______

Overall Score ______

(Sum of above, divided by 7 (or number of factors scored)

<6.0 Poor 6.1 – 7.4 Fair 7.5 –8.9 Good >9.0 Excellent

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Natural channel; no Evidence of past channel Altered channel; <50% of Channel is actively structures, man-made alteration, but with visible the reach shows signs of or widening. channels. No evidence of recovery of channel and channelization. A braided >50% of the reach shows downcutting or excessive banks. Any are set channel. Levees restrict channelization. The stream lateral cutting. back to provide access to an plain width. is restricted from its flood adequate flood plain. plain by levees.

10 7 3 1

Figure 1. You can see the original stream (a) and how over time it has changed direction or meandered. http://web.gccaz.edu/~lnewman/gph111/topic_units/fluvial/fluvial2.html

Channel Conditions surrounding the stream, it is showing of water, causing backwards waves. Let’s start by defining a channel as “the signs of lateral cutting. You may see manmade structures like area where water flows continuously exposed pipes and bridge footings or periodically between a stream bank Looking at our reach, if there are signs that were at one time underwater, now and over a .” In simpler of unnaturally straight sections, high exposed due to a lowered streambed. terms, it’s the place where the stream stream banks, or there are no signs Signs of built up along loops flows. Channel conditions are the factors of pools, , or , the stream and curves of the stream, called point that may affect the direction of flow of might be channelized. Streams that bars, indicate a channel in the process these channels (see the glossary for the already have been channelized may not of changing direction. Another indicator explanations of the words in bold). have as much vegetation in or around it. of channelization is woody vegetation In older channels with channelization, below the bank. Looking at all these Determining the condition of the channel there will be lack of woody vegetation factors, you must determine the level of always involves two factors: water flow, like trees and shrubs and more grasses. channelization and meandering and rate and the stability of the bank and stream Signs of downcutting include riffles it based on the given scale. bed. The flow of the water will determine facing the opposite direction of the flow the amount of sediment added or removed, from the channel and how fast changes in the channel will occur. Bank and Stream beds determine how deep the stream flows, and the direction it will flow through the watershed. The change of direction in the channels is called meandering (figure 1), when a channel veers from its natural path. When a stream erodes downward, below the natural stream bed, it is showing signs of downcutting. When the stream cuts across the bank into the land Figure 2. A visual representation of a natural streams jagged flow and it being straightened through channelization. https://www.geocaching.com/geocache/GC5TCT6_channelized-river-restoration 4 U.S. Fish & Wildlife Service

Natural vegetation extends Natural vegetation extends Natural vegetation extends Natural vegetation less at least two active channel one active channel width on a third of the active channel than a third of the active widths on each side. each side. or width on each side. Filtering channel width on each side. If less than one width, covers ability is moderately or Lack of regeneration. entire flood plain. or compromised. Filtering function severely Natural vegetation extends compromised. half of the width of the active channel on each side. 10 7 3 1

Riparian Zone This is the easiest and most important characteristic to look at when it comes to stream assessments. The riparian zone can be defined as the amount of vegetation that surrounds the streams banks. This zone serves as a buffer between the stream and any surrounding sources of runoff. The buffer area is often made up of vegetation such as trees, bushes, and shrubs —­ plants that soak up potentially hazardous materials, recycling them into the environment before they are able to pollute the stream directly. Rain water is also soaked up in the riparian zone, feeding into the below the stream and contributing to the that establishes a . Figure 3. A visual representation of stream zones. See the riparian zone is the The riparian zone also provides shaded immediate buffer between uplands and the stream banks. areas along the banks of the streams http://slco.org/watershed/streams-101/the-riparian-zone/ that provide habitat for fish like bass and catfish. The riparian zone should be present on both sides of the stream in equal widths. These areas also provide a brake system of sorts—water rushing down hills (or other steep inclines) towards the stream is slowed down by the roots and leaves of plants, allowing for less erosion of sediment into the stream.

When looking at the riparian zone, check for complete and thorough plant communities. Are there multiple species present, including plants with various leaf sizes flowering types, and root structures? Look between the stream and the nearest or human-disturbed area. Is there a big enough buffer where water can be slowed down before it reaches the stream? Make sure there are healthy riparian zones on BOTH sides of the stream as well. You do not want one side to be protected and the other slowly (or quickly) eroding away!

Lake Woodruff, credit USFWS/E Tramontana

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Banks are stable; banks are Moderately stable; banks are Moderately unstable; flooding Unstable; banks may be low (at elevation of active low (at elevation of active occurs 1 year out of 5 or low, but typically are high; flood plain); 33%< of eroding flood plain); <33% of eroding less frequently; overhanging inside and outside bends are surface area along the banks surface area of banks is vegetation at top of bank, some actively eroding as well as is protected by roots that protected by roots that extend mature trees falling into steam outside bends. Numerous extend to the base-flow to the baseflow elevation. annually, some slope failures slope failures apparent. elevation. apparent. 10 7 3 1

Figure 4. An example of poor bank stability slowly eroding around the roots of the tree.

Bank Stability If you’ve ever seen little caverns created When grading the bank stability, look The riparian zone leads directly into under big tree roots creating along for good vegetation, trees and shrubs the bank stability. Large tree roots and the bank, this CAN be a sign of poor bank with good root systems that can hold soil structures allow for stable foundations stability. Remember, all banks erode over together. Grasses and small plants may along stream banks. This is important time so even a bank that may be 50% not have enough extensive roots to be for the same reasons as riparian zones, eroded can still be stable enough for that able to hold up against erosion or flood reducing erosion and provided stable stream to continue. It all depends on the levels. ground for vegetation to grow. Banks baseflow (flow at normal height) and the can in or crash down when they are type of soil around the banks. undercut by flowing water. 6 U.S. Fish & Wildlife Service

Very clear, or clear but tea- Occasionally cloudy, Considerable cloudiness Very turbid or muddy colored; objects visible at especially after storm event, most of the time; objects appearance most of the time; depth 3 to 6 ft (less if slightly but clears rapidly; objects visible to depth 0.5 to 1.5 ft; objects visible to depth < 0.5 colored); no oil sheen on visible at depth 1.5 to 3 ft; may slow sections may appear ft; slow moving water may be surface; no noticeable film have slightly green color; no pea-green; bottom rocks or brightgreen; other obvious on submerged objects or oil sheen on water surface. submerged objects covered water pollutants; floating rocks. with heavy green or olive- algal mats, surface scum, green film. or Moderate odor of sheen or heavy coat of foam ammonia or rotten eggs. on surface. or Strong odor of chemicals, oil, , other pollutants. 10 7 3 1

Water Appearance This characteristic is very visual. Compare what your image of clear water is, probably our drinking water, to that of a typical stream. Would YOU swim in it? That is usually a good indicator of clarity. Water clarity can be determined by assessing the water’s color and its turbidity (the measure of how murky the water is based on the amount of sediment is in the water). There is expected to be a significant amount of sediment present in streams that indicates a healthy flow. Signals of poor water appearance include cloudy, milky looking water, or signs of pollution like like foam or oils on the water. Water appearance can be relatively easy to assess, if it doesn’t look healthy and habitable, it probably isn’t!

Within this category, look for pools of water. These are areas where there is little to no flow of water into or out of the area, thus creating little pools just Loakfoma Creek, credit USFWS like those in backyards. Pools can be shallow or deep and are important fish feeding and breeding grounds. A healthy stream should have a mix of shallow and deep pools, the depth depending on the surrounding overall depth of the stream. If little to no water is running between the pools and the stream, the pools may be prone to harboring algae or collecting or collecting other hazardous materials. Looking at your stream, one to two pools is normal to see for the reach assessed.

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Clear water along entire Fairly clear or slightly Greenish water along entire Pea green, gray, or brown reach; diverse greenish water along entire reach; overabundance of lush water along entire reach; community includes low reach; moderate algal growth green macrophytes; abundant dense stands of macrophytes quantities of many species on stream substrates. algal growth, especially clog stream; severe algal of macrophytes; little algal during warmer months. blooms create thick algal growth present. mats in stream. 10 7 3 1

Nutrient Enrichment Nutrient enrichment can be measured by the species and number of aquatic vegetation in the water. Visible rooted aquatic plants (called macrophytes) provide food and hiding habitat for fish and macroinvertebrates. Seeing vegetation in a stream is normal and can indicate a healthy stream, but too much vegetation can cause problems for the organisms that live there. Aquatic plants use oxygen just like those on land and when they die they soak up the dissolved oxygen in the water, leaving the water unbreathable for fish. High nutrient levels can cause unsustained algal growth.

When assessing nutrient enrichment, you want to see clear water with a diverse aquatic plant community. Areas were there an overabundance of aquatic plants or algae film on top of the water indicates unhealthy levels of nutrients.

Pigeon River, credit USFWS/Gary Peeples

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At least five types of habitat Three to four types of habitat. One to two types of habitat. None to one type of habitat. available. Habitat is at a Some potential habitat exists, The substrate is often stage to allow full insect such as overhanging trees, disturbed, covered, or removed colonization (woody debris which will provide habitat, by high stream velocities and logs not freshly fallen). but have not yet entered the and scour or by sediment stream. . 10 7 3 1

Macroinvertebrates Observed based on which ones are present. Streams Macroinvertebrate Habitat Macroinvertebrates (animals without can be deemed healthier upon visual Habitat for macroinvertebrates include a backbone that can be seen by the assessment based on the sighting of more woody debris, submerged logs, dense human eye) observed in a stream can sensitive species. Use the guide provided mats of fallen leaves, boulders, and coarse imply a lot about the ability of the to determine if the “bugs” you see in the gravel. Shaded areas along the bank tend stream to support aquatic invertebrate water are sensitive or tolerant species. to be great spots for larvae and other animals. For the purpose of this guide, insects to be flitting across the surface. macroinvertebrates are divided into four How to Sample for Macroinvertebrates Areas with a diverse amount of suitable categories: ‘tolerant’, ‘semi-tolerant’, You can collect macroinvertebrates by habitat and high stability in these areas ‘sensitive’, and ‘very sensitive’ (to water hand by picking up and looking under will promote a healthy macroinvertebrate pollution). The presence of ‘sensitive’ and stones, however, the most effective way population. ‘very sensitive’ species indicates healthy is to use a stream bottom sampling net. stream conditions; the abundance of A common net is a “D-net”, which is used Look for areas where the vegetation ‘tolerant’ species indicates poor water by setting the net a little bit downstream creates a shadow over the water to quality. Please see the macroinvertebrate from where you are agitating the stream provide cool areas. Places where trees identification sheet on the next page. bottom with your foot. Here is a link have fallen or branches and roots dip into These small animals can be a great to a demonstration on how to properly the water usually provide good insect indicator into the health of the stream sample: https://www.youtube.com/ habitat as well. watch?v=ftJuAi9Pj7U

Little Tennessee River, credit USFWS/Gary Peeples 9 U.S. Fish & Wildlife Service

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Flooding every 1.5 to two Flooding occurs only once Flooding occurs only once No flooding; channel deeply years. No , no water every three to five years; every six to ten years; incised or structures prevent withdrawals, no structures limited channel incision. or channel deeply incised. or access to flood plain or limiting the stream’s access Stream withdrawals are Withdrawals significantly Withdrawals have caused to the flood plain. Channel is occurring but do not affect affect available low flow severe loss of low flow not cut by braiding. available habitat for biota. habitat for biota. habitat. or Flooding occurs on a one-year rain event or less. 10 7 3 1

Hydrologic Alterations When a stream , how does that affect the way the stream flows? How does it affect the sediment in the stream, and the living creatures that live in the stream? Answering these questions addresses the stream’s responses to hydrologic alteration.

A stream’s flood plain area (the area around the stream that through time has been used to hold flood waters as the stream overflows) interacts with hydrologic alterations to create stream diversity. Human land use within and around the flood plain (including tree clearing, run- off, or agricultural use), affect the way a channel will interact with its corresponding flood plains.

Water flows moves around Figure 5. This picture shows a stream that has experienced a division of the main stream, creating both sediment of varying these smaller and weaker streams. This is an example of braiding. sizes and substances, and Credit: United States Geological Survey; Image source: Earth Science World Image Bank woody debris like fallen http://www.earthscienceworld.org/images Copyright © Bruce Molnia, Terra Photographics branches and logs, which provides diverse for living If a channel has no distinction between generally stretches the original channel creatures throughout the entire stream. the flood plain and the bottom of the too thin, and it creates poor habitat. High flowing water cleans gravel and channel, there will be a lack of overflow, larger sediment pieces for fish and and thus a lack of sediment movement, When assessing the physical stream, aquatic animals, while low flowing water which cause the stream channel to look for flood lines (water marks along creates pools and ripples. widen. Well-established banks encourage the bank), sediment deposits, and stream sediment movement, which reduces debris along the bank. Extra sediment Baseflow is the stream water that comes the chance of channel widening, and deposits along the bank and shallow from the ground, not runoff from rain or channel braiding. Braiding (figure 3) is channels shows the possibility of braiding snow. Placement of human structures like defined as channels splitting into three to occur, which is not good for habitat. irrigation systems and dams affects the smaller and more shallow channels that baseflow to streams during drought, and lack good habitat for living creatures When grading a stream on hydrologic the overall normal flow of that stream within the stream. T Splitting a stream alteration, look for signs of high sediment throughout the seasons When base flow into two channels can be positive, since movement by the water. Does it seem like runs low, overall stream flow is affected, the two new stream reaches tend to be a lot of dirt is being washed away from and it can result in poor habitat for more stable, providing stable habitat the banks? Look for signs of flooding, organisms. for species entering the new .A like water marks on trees, or vegetation large channel splitting into three pushed back from the banks. 12 U.S. Fish & Wildlife Service

Glossary Active channel width The width of the stream at the bankfull . Permanent vegetation generally does not become established in the active channel **Baseflow The portion of that comes from from groundwater, not water runoff; average stream discharge during low flow conditions Bottom-dwelling or substrate-oriented organisms Biological indicator Something that provides clues about the health of an environment based on its presence or absence, or certain physical characteristics/manifestations. For example, frogs are good biological indicators of water quality because they are more sensitive to pollutants than Little River mussel, credit USFWS/Gary Peeples many animals. If water quality is poor, frogs may have unusual characteristics Intermittent stream such as missing toes or extra limbs, or be A geologic area defined by similarity A stream I contact with the ground water entirely absent from the area. of climate, , soil, potential table that flows only certain times of the natural vegetation, , or other year, such as when the groundwater table Braiding ecologically relevant variables. is high or when it receives water from the A series of channels created when a surface source main stream splits off into smaller parts Ecosystem separated by of or sediment. A community of organisms that interact Lateral cutting Smaller channels that are created are with each other within a physical See degredation; along the width of the considered the braids. environment stream Boulders Flood plain Large rocks measuring more than 10 The flat area of land adjacent to a stream A winding section of stream with many inches across that is formed by flood processes bends that is less than 1.2 times longer, following the chanel, than its straight- Channel Grass line distance. A single meander generally A natural or artificial waterway of An annual to perennial herb, generally comprises two complete opposing bends, perceptible extent that periodically or with round erect stems and swollen nodes starting from the relatively straight continuously contains moving water. It Gravel section of channel just before the first has a definite bed and banks that serve to Small rocks measuring 0.25 to 2.5 inches bend to the relatively straight section just confine the water. across after the second bend Channelization Habitat Macroinvertebrate Straightening of stream channel to make The area or environment in which an A spineless animal visible to the naked water move faster. animal lives eye or larger than 0.5 millimeters. These are organisms that do not have a skeleton Cobbles Hydrology and are fairly small, but can still be seen Medium-sized rocks which measure 2.5 to The study of the properties, distribution, with the naked eye. These can be aquatic 10 inches across. and effects of water or Earth’s surface, worms, crayfish, larva, and soil, and atmosphere more. Though small, these animals are Geologic process by which a stream important to a balanced ecosystem, and Incised channel bottom is lowered in elevation due to can even be biological indicators (**refer A channel with a streambed lower in the net loss of substrate material as it to the macroinvertebrate identification elevation than int historic elevation in is washed downstream. Often called pamphlet to see which species are relation to the downcutting. tolerant or not…) Downcutting See degradation. 13 U.S. Fish & Wildlife Service

Nonpoint source pollution Riparian Substrate Pollution (such as runoff from farmland, The zone adjacent to a stream or any The mineral or organic material that etc.) that is not confined to a single point other waterbody forms the bed of the stream; the surface on which aquatic organisms live Run A stream that flows continuously A fast-moving section of stream with little Turbidity throughout the year surface agitation The depth to which an object can be clearly seen is a measure of turbidity. Point Runoff This can be measured by lowering a disk A gravel or sand deposit on the inside of a The draining of water downhill off of (called a secchi disk) into the water until meander; an actively mobile river feature surfaces such as paved , buildings, it disappears. The depth you can lower cars, etc. As water moves this way across the disk before it disappears can be used Point source pollution the landscape, it picks up the pollutants it Pollution from an identifiable source to determine the clarity of the water. The encounters and takes them with it. When lower the depth, the more clear. Pollutant the runoff droplets eventually reach the A substance or energy introduced into a water system of the watershed, they alt. Turbidity specific environment that has undesired bring those pollutants with them, thereby Murkiness or cloudiness of water caused effects or adversely affects the usefulness polluting the water source. by particles, such as fine sediment (, ) and algae of a resource. Scouring Pool The erosive removal of material from the Watershed Deeper area of a stream with slow- stream bottom and banks A ridge of high land dividing two areas moving water that are drained by different river Sediment systems. The land area draining to a Reach Naturally occurring material found at the waterbody or point in a river system; A section of stream (defined in a variety bottom of streams that is broken down by catchment area, , drainage of ways, such as the section between erosion. It typically either settles on the area or a section with consistent stream bed, or is transported by stream characteristics) flow to other parts of the stream. alt. Watershed An area of land where water runs Stream bed downhill to the same or A shallow section in a stream where The bottom of the stream or river water system. Its function is to collect water is breaking over rocks, wood, channel, contained between the banks of rainfall, store it as groundwater, and or other partly submerged debris and the stream. eventually allow that water to drain into producing surface agitation streams, , and oceans.

Tuskasegee River, credit USFWS/Gary Peeples

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