Washington County Government Center Stormwater Management Planning

Stillwater, Minnesota

In need of expansion to accommodate population growth, Washington County developed a plan for the Government Center that included adding facilities to the campus. Using that plan, SRF developed a Stormwater Management Plan to address discharge, detection and elimination; construction site runoff control; post-construction site runoff control; and pollution prevention/good housekeeping items.

SRF first completed a hydrologic and hydraulic evaluation of the site and stormwater conveyance systems based on survey information, hydrologic computations, and discussions with facility management personnel.

Next, SRF conducted a stormwater analysis of the campus to determine water quantity and quality criteria. These criteria guided the development of three best management practices (BMPs) application scenarios that would meet or exceed the goals set during the analysis stage.

Washington County then selected a scenario for final design, which included construction of ponds and infiltration basins. SRF prepared plans and specifications and the ponds and basin were constructed in 2007. SRF also developed construction plans for rain gardens associated with a future parking lot expansion.

CLIENT: Washington County Highway Department