What is a Watershed?

A watershed is an area of land that drains all the streams and rainfall to a common outlet such as the outflow of a reservoir, mouth of a bay, or any point along a stream channel. The word watershed is sometimes used interchangeably with drainage basin or catchment and is an area which consists of surface water lakes, streams, reservoirs, wetlands, and all the underlying ground water. 

 

In the Eau Claire River Watershed, our streams, rivers, and lakes are fed primarily by precipitation, surface water runoff, and groundwater. Our cool groundwater springs are particularly important water sources for many of our smaller streams that are highly vulnerable to changes in land use, soil health, and surface water runoff.

​

Watersheds are important because the streamflow and water quality of a river or lake are affected by things, human-induced or not, happening in the land area “above” the river outflow point. In the past, management of water resources traditionally focused on surface water or ground water as if they were separate entities. As development of land and water increases however, it is observed that both resources are affected by the quantity and quality of the other since nearly all surface water features interact with groundwater (USGS, 2013).