Around the Water Cooler: Spotlight on Small Streams

By Sarah Blau

That small trickle of water you routinely step over as you walk your dog every morning is probably one of many local streams that feed the lake down the street where neighborhood children splash around on hot summer days. Most lakes and rivers are fed by networks of smaller rivers or streams, which, in turn, are fed by smaller and smaller streams.

Small streams, like the hypothetical one I just had you walking your hypothetical dog over, are often unnamed and rarely appear on maps, and yet the health of small streams is critical to the health of the entire river network and downstream communities. Small stream ecosystems include more than 72% of U.S. river miles, and it makes sense that the quality of this vast amount of inconspicuous water may impact the condition of local and downstream ecosystems.

For these reasons, EPA researchers run the Experimental Stream Facility (ESF), one of only a handful of research facilities in the country designed to conduct small stream research.

Located near Milford, OH, the ESF has experimental small-scale streams, or “mesocosms” for studying the effects of various environmental stressors on stream ecosystems. Each study is designed to provide information on small stream ecosystem structure and function that can be used for the development and testing of identifiers for stream health, water quality monitoring tools, or watershed monitoring and modeling strategies.

EPA's Experimental Stream Facility

The research at this facility is particularly meaningful in light of a recently released EPA report on streams. The National Rivers and Streams Assessment was released for public comment last week and reflects the first comprehensive survey looking at the health of thousands of stream and river miles across the country. Unfortunately, the assessment reveals that more than half are in poor condition for aquatic life, among other findings.

The findings of this assessment will inform decisions to address critical needs around the country for rivers, streams, and other water bodies. Sampling for a second nation-wide assessment of rivers and streams will being in May, 2013.

The first step for us, I believe, is simply to notice these streams. The dog may be hypothetical, but the streams are all around us and need protecting just as much as the lake down the street.

About the Author: Sarah Blau is a student services contractor working on the Science Communications Team in EPA’s Office of Research and Development. She often walks her real-life dog down to the lake at the end of her street by way of numerous small stream crossings.

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