What is a watershed?

A watershed refers to an area of land that drains to a common water body such as a lake or stream. Watersheds vary in size and shape. Large watersheds are comprised of smaller or "nested" watersheds. A Hydrologic Unit Code, or HUC, is used to identify specific watersheds at different scales. The number of digits in a HUC indicates the relative scale of the watershed. The smaller the number, the larger the watershed. In Kansas, there are approximately 2020 HUC 14 watersheds nested within 355 HUC 11 watersheds, which are in turn nested in approximately 90 HUC 8 watersheds.