Impaired Water Bodies

What are impaired water bodies?

Streams, rivers and lakes are used for recreation and fishing and may provide water for drinking or agriculture. When water is contaminated by pollutants, the water bodies are considered impaired. These impairments are related to the amount of pollution that has occurred in or near the water body. Groups such as tribal or low income communities may depend on fish, aquatic plants and wildlife in nearby water bodies more than the general population.

Why is this indicator included in CalEnviroScreen?

Impairments can prevent recreational and other uses of the water body.
Water pollution can harm wildlife habitats and change the number and types of plants and animals in the environment.
When fish and shellfish are contaminated, people who eat them can be exposed to toxic substances.

How do we measure impairments to bodies of water in CalEnviroScreen 4.0?

The State Water Resources Control Board maintains information on water bodies in California that are impaired by pollutants.
The indicator combines the number of pollutants in all water bodies designated as impaired in each census tract.
A complete description of the Impaired Water Bodies indicator can be found in the CalEnviroScreen 4.0 report.