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What is a watershed?

We all live in one! The land area that drains or “sheds” to a low point in the landscape such as to a river, lake or wetland is a watershed. There are different classifications of watersheds from basins to subwatersheds. Think about where the rainfall goes in a yard after it rains. It drains to the street, into a storm drain and into a local stream or lake. This, on the smallest scale, is one form of watershed. The quality of water draining off your land directly impacts your local stream and lake quality.

There are many land use activities that impact water quality in watersheds. One of them is directly tied to the amount of impervious surface in a watershed. Urban areas have surfaces that don't absorb water, such as roads, streets, rooftops, parking lots, and even compacted soil. Studies indicate that as the amount of impervious surface increases in urban areas the poorer the stream quality. 


Watershed Challenges

In all watersheds there are upstream and downstream land owners as water passes through many jurisdicational boundaries – this diversity of land use and ownership can be a challenge when coordinating efforts to improve and protect water and soil quality and reduce flooding impacts on a watershed level. Working on a watershed level starts with stakeholders working together to create consistent land use Plans and Policy and employing Practices to prevent water pollution, reduce stormwater runoff and minimize flooding downstream.


Watershed Links

  1. U.S. EPA Surf Your Web
  2. Iowa Watershed Atlas
  3. Center for Watershed Protection
  4. Watershed Planning Grants
Source: Polk SWCD
Source: Polk SWCD
Source: Polk SWCD
Source: Polk SWCD