Title
Resolution to Approve an Agreement with the Washtenaw County Water Resources Commissioner to Evaluate and Identify Opportunities for Stormwater Improvements in the Swift Run Creek Drainage District (Total Estimated Cost: $250,000.00)
Memorandum
Attached for your approval is a resolution to enter into an agreement with the Washtenaw County Water Resources Commissioner (WCWRC) to undertake a project to evaluate and identify opportunities for conveyance and stormwater improvements in the Swift Run Creek Drainage District.
Swift Run is relatively small creekshed in the Huron River watershed. It begins in farm fields in Pittsfield Township, flows through the City of Ann Arbor's landfill, under the US23 and Washtenaw Avenue interchange, and into South Pond before entering the Huron River at Gallup Park.
During significant rain evens, stormwater frequently enters the creek too quickly causing localized flooding. These rain events also carry pollutants from impervious areas to the creek, lowering water quality. Swift Run Creek falls within the area of the Huron River watershed that has a Total Maximum Daily Load (TMDL) requirement for phosphorus and E. coli from stormwater set by the Michigan Department of Environment, Great Lakes and Energy (EGLE). In addition, Swift Run Creek has a creek-specific TMDL for biota, which is attributed to unstable flow regimes, reduced bank stability, bank erosion, sedimentation and reduced stream quality due to excessive runoff or washout throughout the highly urbanized watershed.
The original Middle Huron River Watershed Management Plan (WMP) was completed in 1994, updated in 2000, 2008, and 2011. Most recently, the WMP was again updated in 2020. Overall, the WMP identified long-term goals to address large-scale watershed-wide needs, including:
* Reduce flow variability.
* Reduce nonpoint source loading and reduce soil erosion and sedimentation.
* Protect and mitigate loss of natural features for stormwater treatment a...
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