Wadeable streams are small and shallow enough that researchers can get adequate water samples by wading into the streams. About 90 percent of perennial stream and river miles in the United States are small, wadeable streams. Even though they are small, wadeable streams can have a big impact by carrying soils and pollutants downstream into bigger streams and rivers.
The EPA’s Wadeable Streams Assessment, conducted in 2006 with samplings from 1,392 random stream sites, looked at the condition of these small streams. In the plains and lowlands region of the United States, 40 percent of stream miles were in poor biological condition. Biological condition is based on a sampling of benthic macroinvertebrates. These are small animals, including insects, beetles, flies and snails, living in the sediments at the bottom of streams. Data on benthic macroinvertebrate communities help determine the health of a stream. The top stressors identified were nitrogen and phosphorous pollution, streamside disturbances from human activities like clearing vegetation, and instability of the streambed.
Viewer Tip: You can help keep wadeable streams healthy where you live. If there is a wadeable stream near your home, plant trees and shrubs along the stream banks to keep soils and pollutants out of the water. When it rains, the plants along the stream bank will help filter pollutants out of rain water and hold soil in place to prevent erosion.
(Sources: EPA, “Wadeable Streams Assessment,” http://water.epa.gov/type/rsl/monitoring/streamsurvey/upload/2007_5_16_streamsurvey_WSA_Assessment_May2007.pdf; EPA, “Nutrient Pollution,” http://www2.epa.gov/nutrientpollution)