A watershed is the area that drains to a common waterway, such as a stream, lake, estuary, wetland, aquifer, or even the ocean. We all live in a watershed and our individual actions can directly affect it.
Diagram courtesy of Arkansas Watershed Advisory Groups
Water Quality and Land Use
How land is used throughout a watershed affects water quality. Development alters the land which changes the way water is transported and stored. Impervious surfaces (e.g. driveways, roads, sidewalks, rooftops, etc.) and compacted earth associated with development create barriers to rain and snowmelt infiltration. These alterations may also change the physical characteristics of a stream, thereby degrading habitat for aquatic life. The results include:
• decreased water quality;
• increased volume and velocity of runoff;
• degradation of aquatic life habitat;
• increased frequency and severity of flooding;
• peak (storm) flows many times greater than in natural basins;
• loss of natural runoff storage capacity in vegetation, wetland, and soil;
• reduced groundwater recharge;
• decreased base flow (the groundwater contribution to stream flow).