Chemical Monitoring Instructions for Stream Monitors

Share your stream monitoring data at www.cleanwaterhub.org.

I Z A A K W A L T O N L E A G U E O F A M E R I C A

As you explore your stream’s water chemistry, it is important to understand that water chemistry is very complex. While

some chemicals are absolutely necessary for life (such as nutrients) others can be harmful (such as pesticides) or harmful

in large amounts (back to nutrients). Some chemicals may not directly affect human health, while others (such as nitrate)

can have harmful effects in our drinking water.

The following are a few examples of how environmental

conditions can influence water chemistry:

 Time of day: Dissolved oxygen levels rise during sunlight

hours due to increased photosynthesis in aquatic plants

and algae. Levels decrease overnight when

photosynthesis is not occurring and plants and animals

are using up dissolved oxygen.

 Weather: Runoff from heavy rains can transport

pollutants into streams (which is called nonpoint source

pollution). Very dry conditions over a long period of time

(drought) lower stream flow, raising the concentration of

chemicals in the stream.

 Physical influences: Decreased canopy cover causes

sunlight to warm the water, which can decrease

dissolved oxygen levels.

 Land use: What we do on the land greatly affects the

volume of stream water flow and quality of our streams’

water, including:

o Development (filling in of wetlands; runoff from paved

areas, roofs, and lawns with their many applied

chemicals)

o Agriculture (runoff containing crop chemicals and

animal waste, tilling of the land, and filling in of

wetlands

o Recreation (clearing of land, chemical applications,

introduction of invasive species)

Monitoring should be conducted at the same station

(location) each time. Carefully record the location of your

monitoring station on your Chemical Monitoring Data Form.

Include roads, bridges, and significant landmarks. Use your

smart phone’s GPS functionality to determine your

longitude and latitude.

USE AND STORAGE OF TESTING MATERIALS

Chemicals in test kits, though not dangerous, can cause

mild skin and eye irritation and should be handled with

care. Ampules are made of glass and can be very sharp.

Test strips along with waste materials can be disposed of

as you would any household item.

Store all chemical testing materials at room temperature.

Dissolved oxygen and phosphate testing kits must be

stored in the dark. Check expiration dates and avoid using

expired materials (which could provide inaccurate results).

You can find links to purchase stream monitoring test

kits and equipment on the Izaak Walton League website at

iwla.org/water/resources-for-monitors.

DISSOLVED OXYGEN

Dissolved oxygen (DO) is necessary for nearly all aquatic

life to survive. Certain processes add oxygen to a stream,

while others remove or consume oxygen. Oxygen is added

to a stream from the atmosphere through mixing in

turbulent areas. Plants also contribute oxygen through

photosynthesis. DO in streams can be affected by:

 Water Temperature: Cold water holds more oxygen than

warm water.

 Time of Day: On a sunny day, DO levels rise from morning

through the afternoon as a result of photosynthesis, reach

a maximum in late afternoon, and steadily fall during the

night, reaching their lowest point before dawn.

 Stream Flow: DO will vary with the volume and velocity

of water in a stream. Faster moving water mixes readily

with atmospheric oxygen, thus increasing DO.

 Aquatic Plants: Plant and algae growth in a stream will

affect the oxygen contributed by photosynthesis during

the day and depleted by plant respiration at night.

 Dissolved or Suspended Solids: Oxygen dissolves more

readily in water that does not contain high amounts of

salts, minerals, or other solids.

 Human Impacts: Lower DO levels may result from

human impacts including organic enrichment, urban

stormwater runoff, riparian corridor removal, stream

channelization, and dams.

CHEMICAL MONITORING INSTRUCTIONS FOR STREAM MONITORS

Share your stream monitoring data at www.cleanwaterhub.org.

Typical range for dissolved oxygen = 8.7 to 12.9

mg/L (rivers); 7.4 to 10.4 mg/L (lakes)

Reporting Technique: For use with the CHEMetrics

dissolved oxygen test kit

1. Check the expiration dates on all materials in the kit. If

materials have expired, DO NOT USE them.

2. Remove the 25 ml sample cup from the kit and rinse it

three times with stream water.

3. From your monitoring station, wade straight out to the

spot with the greatest flow of water and, facing

upstream, fill the sample cup to the 25 ml mark, mixing

the water and air as little as possible.

4. Lower the sample cup down to wrist depth while

holding it upside down. Turn the opening downstream

so that the cup backfills with water, then turn the cup

upstream and carefully remove cup and water sample

from stream.

5. Gently tip the sample cup to pour off excess water.

6. Place the ampoule in the sample cup, tilting it so the tip

is wedged in one of the spaces along the side of the

sample cup.

7. Snap off the tip of the ampoule by pressing it against

the side of the cup, allowing it to fill with water.

8. Remove the ampoule from the cup and mix the water

by inverting the ampoule several times. Be careful not

to touch the broken end, as it will be sharp.

9. Two minutes after you break off the ampoule tip,

compare the ampoule to the color standards provided in

the kit. Remove sunglasses before making a color

determination. NOTE: It’s important to read the ampoule

exactly at two minutes – it will continue to change color.

10. Hold the comparator nearly flat while standing directly

beneath a bright source of light. Place your ampoule

between the color standards moving it from left to right

until the best color match is found. Record your result

on the Chemical Data Form.

Avoid breaking the ampoule open, as the contents may be

mild skin and/or eye irritants.

pH is a measure of a water’s acid/base content and is

measured in pH units on a scale of 0 to 14. A pH of seven

(7) is neutral (distilled water), while a pH greater than

seven is basic/alkaline and a pH less than seven is acidic.

The pH level of stream water is influenced by the

concentration of acids in rain and the types of soils and

bedrock in the state. The typical pH of rainfall in the United

States is slightly acidic, ranging from 5.0 to 5.6.

Rainwater pH is determined by natural atmospheric

processes and human activities (e.g., industry emissions

causing acid rain). Low pH levels (acidic) can have a

harmful impact on the health of aquatic communities.

Most aquatic organisms require habitats with a pH

of 6.5 to 9.0.

Reporting Technique: For use with Hach® pH test strips

1. Check the expiration date on the bottom of the bottle. If

the test strips have expired, DO NOT USE them.

2. From your monitoring station, wade straight out to the

spot with the greatest flow of water and, facing

upstream, dip the test strip in the water and remove it

immediately.

3. Hold the test strip level for 15 seconds. DO NOT SHAKE

excess water from the test strip.

4. Estimate pH by comparing the test strip to the color

chart on the test strip bottle. Remove sunglasses before

reading the strip. The strip will continue to change

color, so it is important to make a color determination

immediately after 15 seconds.

5. Record results on the Chemical Data Form.

CHLORIDE

Chloride is a chemical found in salts, which tend to

dissolve easily in water. Elevated levels of chloride in a

stream may indicate inputs of human/animal waste or from

fertilizers, many of which contain salts. During winter

months, elevated chloride levels may occur as a result of

road salt runoff into nearby streams. Chloride can be used

as a conservative measure of water contamination since

other natural processes, such as breakdown by bacteria,

do not affect it.

Typical range for chloride = 16 to 29 mg/L (rivers)

Reporting Technique: For use with Hach Chloride

QuanTab® titration strips and a sample cup from one of

the CHEMetrics test kits.

1. Check the expiration date on the side of the bottle. If the

test strips have expired, DO NOT USE them.

2. Rinse the sample cup three times with stream water.

3. From your monitoring station, wade straight out to the

spot with the greatest flow of water and, facing

upstream, fill the sample cup with approximately 1 inch

of water.

CHEMICAL MONITORING INSTRUCTIONS FOR STREAM MONITORS

Share your stream monitoring data at www.cleanwaterhub.org.

4. Remove a test strip from bottle and replace the cap

immediately.

5. Insert the lower end of the test strip into the sample

cup filled with water. Do not submerge past the yellow

line at the top of the titrator.

6. Allow the sample water to completely saturate the wick

of the titrator. There is no time limit for this test – the

reaction is complete when the yellow line turns dark

(this will take a few minutes).

7. Note where the tip of the white chloride peak falls on

the numbered QuanTab scale. This represents the

QuanTab unit value.

8. Refer to the table on the QuanTab test strip bottle to

convert the QuanTab units into a chloride concentration

(units of ppm or mg/L). Record the result on the

Chemical Data Form.

9. If the QuanTab unit value is below the smallest value on

your test strip bottle, report the chloride concentration

as the lowest concentration listed on the test strip bottle

and make a note in the comments section.

PHOSPHATE

Phosphorus is an essential nutrient for plants and animals

and is usually present in natural waters as dissolved

orthophosphate. Plant growth in surface waters is generally

limited by the amount of orthophosphate present. It is the

simplest form of phosphorus found in natural waters and is

most available for plants to use. In most waters,

orthophosphate is present in very low concentrations. For

our purposes, we will refer to orthophosphate as simply

“phosphate.”

There are natural sources of phosphorus, such as certain

soils and rocks, but most elevated levels of phosphorus

are caused by human activities. These include human,

animal, and industrial wastes as well as runoff from

fertilized lawns and cropland. Excess phosphorus in water

speeds up plant growth, causes algal blooms, and can

result in low dissolved oxygen (“hypoxic”) conditions that

can lead to the death of certain fish, invertebrates, and

other aquatic animals.

Typical range for total phosphorus = 0.11 to 0.34

mg/L (rivers); 0.05 to 0.13 mg/L (lakes)

Reporting Technique: For use with CHEMetrics phosphate

test kit

1. Check the expiration dates on all materials in the kit. If

materials have expired, DO NOT USE them.

2. Remove the 25 ml sample cup and black lid from the kit

and rinse them three times with stream water.

3. From your monitoring station, wade straight out to the

spot with the greatest flow of water and, facing

upstream, fill the sample cup to the 25 ml mark.

4. Gently tip the sample cup to pour off excess water.

5. Add 2 drops of A-8500 Activator Solution, place the

black cap on the sample cup, and shake to mix the

contents.

6. Place the ampoule in the sample cup, tilting it so the tip

is wedged in one of the spaces along the side of the

sample cup.

7. Snap off the tip of the ampoule by pressing it against

the side of the cup, allowing it to fill with water.

8. Remove the ampoule from the cup and mix the water in

the ampoule by inverting it slowly several times. Be

careful not to touch the broken end, as it will be sharp.

9. Two minutes after you break off the ampoule tip,

compare the ampoule to the color standards provided in

the kit. Remove your sunglasses before making a color

determination. NOTE: It’s important to read the ampoule

exactly at two minutes – it will continue to change color.

10. Based on the color of your ampoule, use the

appropriate color comparator to estimate the

orthophosphate concentration.

a. The low-range circular comparator measures

concentrations ranging from 0 to 1 mg/L. To use the

circular comparator, place your ampoule, flat end

downward, into the center tube. Direct the top of the

comparator up toward a good light source while

viewing from the bottom. Rotate the comparator to

match your ampoule to the standards and record

your results on the Chemical Data Form.

b. The high-range comparator in the lid of the kit

measures concentrations ranging from 1 to 10 mg/L.

Hold the high range comparator nearly flat while

standing directly beneath a bright source of light.

Place your ampoule between the color standards

moving it from left to right until the best color match

is found. Record result on the Chemical Data Form.

CHEMICAL MONITORING INSTRUCTIONS FOR STREAM MONITORS

Share your stream monitoring data at www.cleanwaterhub.org.

NITRATE-N/NITRITE-N

Nitrogen is an essential plant nutrient, but excess nitrogen

can cause water quality problems. Too much nitrogen and

phosphorus in surface waters cause nutrient enrichment,

increasing aquatic plant growth and changing the types of

plants and animals that live in a stream. This process,

called eutrophication, can also affect other water quality

parameters such as temperature and dissolved oxygen.

Nitrate and nitrite are two forms of nitrogen.

 Nitrate is very easily dissolved in water and is more

common in streams. Sources of nitrate include soil

organic matter, animal waste, decomposing plants,

sewage, and fertilizers. Nitrate is more soluble in water

than phosphorus and can move more readily into

streams.

 Nitrite is another form of nitrogen that is rare because it

is quickly converted to nitrate or returned back to the

atmosphere as nitrogen gas. Due to its instability,

detectable levels of nitrite in streams and lakes are

uncommon. Detectable nitrite levels in streams may

indicate a relatively fresh source of ammonia.

The amount of nitrate or nitrite dissolved in water is

reported as nitrate-N (nitrate expressed as the element

nitrogen) or nitrite-N in milligrams per liter of water (mg/L).

Stream water nitrate rates may vary greatly depending on

season and rainfall, fertilizer application rates, tillage

methods, land use practices, soil types, and drainage

systems. Consistently high nitrate readings (over 10 mg/L)

may be cause for concern and warrant further

investigation.

Typical range for Nitrate + Nitrite-N = 3 to 8.5 mg/L

(rivers); 0.05 to 0.94 mg/L (lakes)

Reporting Technique: For use with Hach® nitrate-

N/nitrite-N test strips

1. Check the expiration date on the bottom of the bottle. If

the test strips have expired, DO NOT USE them.

2. Dip the test strip into the water for one second and

remove. DO NOT SHAKE excess water from the test

strip.

3. Hold the strip level, with pad side up, for 30 seconds.

4. At exactly 30 seconds, compare the NITRATE (upper)

test pad to the nitrate-nitrogen color chart on test strip

bottle, estimate the nitrate concentration in mg/L, and

record your reading on the Chemical Data Form.

(Remove sunglasses before reading the strip.) The pad

will continue to change color, so make a determination

immediately after 30 seconds.

Note: Each nitrate-N/nitrite-N test strip also has a second

tab for measuring nitrite-N. Save Our Streams chemical

monitoring does not collect nitrite-N data, so you may

disregard this test pad.

TRANSPARENCY

Transparency is a measure of water clarity and is affected

by the amount of material suspended in water. As more

material is suspended, less light can pass through, making

it less transparent. Suspended materials may include soil,

algae, plankton, and microbes. Transparency is measured

using a transparency tube and is measured in centimeters.

It is important to note that transparency is different from

turbidity; transparency is a measure of water clarity

measured in centimeters, while turbidity measures how

much light is scattered by suspended particles using NTUs

(Nephelometric Turbidity Units).

Low transparency (or a high number of suspended

particles) is a condition that is rarely toxic to aquatic

animals, but it indirectly harms them when solids settle out

of the water, which can clog gills, destroy habitat, and

reduce the availability of food. Furthermore, suspended

materials in streams promote solar heating, which can

increase water temperatures (see Water Temperature) and

reduce light penetration (which reduces photosynthesis) –

both of which contribute to lower dissolved oxygen levels.

Sediment also can carry chemicals attached to the

particles, which can have harmful environmental effects.

Sources of suspended particles include soil erosion,

waste discharge, urban runoff, eroding stream banks,

disturbance of bottom sediments by bottom-feeding fish

(such as carp), and excess algal growth.

Reporting Technique: We measure transparency with a

transparency tube that shows how many centimeters down

into the tube you can see the black and white pattern at the

bottom.

1. Make sure the finger clamp on the hose is closed.

2. From your monitoring station, wade straight out to the

spot with the greatest flow of water and, facing

upstream, fill the transparency tube.

3. Hold the tube upright and in the shade. Use your body

to shade the tube if nothing else is available.

4. With your back to the sun, look directly into the tube

from the open top and release water through the small

hose, regulating the flow with the finger clamp until you

are able to distinguish the black and white pattern

(Secchi pattern) on the bottom of the tube. Close the

finger clamp.

CHEMICAL MONITORING INSTRUCTIONS FOR STREAM MONITORS

Share your stream monitoring data at www.cleanwaterhub.org.

5. Read the number on the outside of the tube that is

closest to the water line. Record your reading in

centimeters (cm).

6. If the Secchi pattern is visible when the transparency

tube is completely full of water, record a transparency

reading of 65.0 cm and make a note in the comments

section.

7. Rinse the tube after each use so that the bottom Secchi

pattern does not become dirty and clouded.

WATER TEMPERATURE

Many of the chemical, physical, and biological

characteristics of a stream are directly affected by water

temperature. Some species, such as trout, are quite

sensitive to temperature changes. Water temperatures can

fluctuate seasonally, daily, and even hourly.

Human activities can adversely raise stream temperatures

in a variety of ways., including by:

 Releasing warmed water into a stream from industry

discharges or runoff from paved surfaces

 Removing riparian corridors, which increases solar

heating

 Causing soil erosion, which results in darker water that

absorbs more sunlight

Changes in water temperature affect water quality:

 Cool water holds more oxygen than warm water, so the

amount of dissolved oxygen decreases when

temperatures rise

 The rate of photosynthesis by algae and aquatic plants

increases with higher temperatures

 The metabolic rates of aquatic animals increase with

higher temperatures

 The sensitivity of organisms to diseases, parasites, and

toxic wastes increases with rising water temperatures

Human impacts are most critical during the summer, when

low flows and higher temperatures can cause greater

stress on aquatic life. It is important to note that the

temperature of some streams is normally higher than

others, depending on groundwater flow into the stream,

weather, and other factors.

Reporting Technique: Use a non-mercury thermometer or

meter probe to measure stream temperature. From your

monitoring station, wade straight out to the spot with the

greatest flow of water and place the thermometer or probe

directly into the stream, holding it underwater for at least

two minutes so the reading can stabilize. Record the

temperature on your Chemical Data Form in degrees

Celsius (°C).