Sediment
The last two water resource components, runoff and groundwater flow, both dealt with the idea of the water cycle and water quantity. The water cycle helps one trace the processes a quantity of water goes through from a cloud to the land surface and back to a cloud.
Each water cycle process not only changes the water quantity, but also the water quality. Water quality refers to the physical, chemical, and biological properties of water. The water in streams is not distilled, de-ioned, pure water, but contains various constituents, chemical compounds and ions, and organisms which effect how the water can be used.
One of the most prominent water quality constituents is sediment. When precipitation falls on the land surface, soil or sediment is detached. This detached sediment is transported or delivered by flowing water and gravity. Eventually, the sediment is deposited further downslope or into a stream. The next storm resuspends the sediment and the process is repeated again.
InterWET shows how different factors affect in-stream sediment. The researcher perspective uses a special calculator to show how the amount of detached sediment depends many factors, including the land area, cover, slope, and soil texture. The conservationist perspective gives an interactive map of in-stream sediment at several locations along the streams in the Spring Creek Watershed. The local official perspective uses the results from a hydrologic model to predict how certain local policies may change the amount of detached and delivered sediment in the Spring Creek Watershed over the next 20 years.
Questions or Problems? Let me know at parson@andassoc.com.
Last revision 9/9/01.
Created by Shane Parson, Copyright 1999.
