McMurray Fields Stormwater Treatment and Reuse

Capitol Region Watershed District and the City of St. Paul seek to improve the water quality of stormwater runoff to Como Lake in St. Paul and reuse stormwater to displace potable water use at the McMurray Fields complex within Como Regional Park. The project partners propose the construction of a stormwater reuse and infiltration system that will treat the stormwater volume equivalent of 1.1 inches over the impervious surface of the subwatershed, or 4.9 acre-feet. The drainage area to the proposed system is 130 acres, with 54 acres of impervious surfaces. Como Lake is currently impaired for aquatic recreation due to excessive nutrients, namely phosphorus. The Como Lake TMDL and subsequent Como Lake Management Plan have set a target of 60% reduction in phosphorus loading to the lake. The subwatershed in which the project will be sited currently receives very little stormwater treatment. This project will achieve an estimated 56% reduction in phosphorus load from the subwatershed and will achieve an estimated 7.6% (55 pounds) reduction in overall phosphorus loading to the lake from this single practice. A storm sewer diversion structure was constructed as part of a street reconstruction project completed in 2016 in anticipation of a future stormwater treatment practice at McMurray Fields. In 2022 CRWD completed a feasibility study for the site. Complete engineering design is anticipated to be complete by the end of 2023 and construction is anticipated to begin in 2024. The estimated project cost is $5,332,000 which includes engineering, construction, and construction management. CRWD is requesting a $950,000 CWF grant to cover 20% of the estimated $4,619,000 construction cost.