How to Determine the Health of our Waters

More about rivers and streams:

Water that looks unhealthy probably is unhealthy. On the other hand, water that looks clear or fast-flowing might not really be healthy for people, fish, and other uses. Scientists and community groups use several methods to determine river, stream, or lake health.

Tools For Finding the Health of Rivers, Streams, and Lakes

Survey the animals in and around the water (called "biological indicators"). This provides the most reliable information on water health.
Other animals are also sometimes surveyed in state-funded programs.
Test the water. Do direct chemical and physical tests of the water, for such factors as bacterial contamination, temperature, flow, and acidity. Special tests can measure the amount of toxic chemicals in the water.
Look around. Visually survey the habitat, the area in and around the water.

Why Use More Than One Tool?
Each tool has its particular advantages, as you can find out in detail by selecting the links for each type of assessment. Each also has some limitations. So, for more accurate understanding, public and private agencies responsible for monitoring water health general perform several types of assessments. Then they compare results.

If you are working as a volunteer, your group will probably have the time, equipment, knowledge, or other resources available to do only a limited set of assessments. When this is the case, you can also try to find out results of other assessments performed by your state water agencies or other organizations.

Whenever you do perform tests or surveys, make sure to make your results available to as wide an audience as possible, using those same resources.

See the EPA's Volunteer Monitoring Web site for more information on what you can do.

Biological Indicators | Aquatic Biodiversity | Statistical Primer

How to Determine the Health of our Waters

More about rivers and streams:

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