For each simulation element water flux and transport of sediment and agrichemicals are simulated and then routed through a watershed, i.e., water and chemicals are transported from one simulation element to the next depending on flow characteristics. An integrated user interface for SWAT using ArcView and Avenue. Neitsch, S.L., J.G., Arnold and J.R., Williams. 1999. The Sandusky Watershed, with a drainage area at Fremont of 3,240 km2, is located within the Lake Erie Watershed and Great Lakes basin. The Sandusky River is the second largest of the Ohio rivers draining into Lake Erie.
Tile drainage is used extensively throughout the watershed.
Urban areas within the Sandusky Watershed are Bucyrus, Fremont, Tiffin, and Upper Sandusky, and numerous smaller communities. The river and its major tributaries support important recreational uses for watershed residents. Bedrock underlying the watershed is primarily Silurian dolostone and Devonian limestone. In the eastern portion of the watershed, Devonian shale and Mississippian sandstone are present. Surface features of the Sandusky Watershed reflect the effects of the Wisconsinian glaciers, which retreated approximately 13,000 years ago.