Project overview
Urban stormwater management practices aim to reduce the negative impacts of impervious surfaces covering the landscape. This can be accomplished by redirecting stormwater runoff onto pervious (or permeable) surfaces, like lawns, gardens, or parklands, and allowing the water to infiltrate into the ground. Small, distributed stormwater BMPs (best management practices), like rain gardens and bioretention basins, are often utilized to accomplish these stormwater goals.
Many methods have been proposed for measuring the cumulative impacts of these small, distributed BMPs. However, their cumulative effect is not fully understood. This project will test two of the most promising measurement methods on two large datasets. The modeled results will then be verified by comparing them to data collected from a pair of watersheds: one in St. Paul, MN and another in Madison, WI. This work will relate the amount of stormwater infiltration to the abundance, distribution, and/or type of stormwater BMPs present in these watersheds.
Research questions
What are the aggregate runoff volume and pollutant reduction benefits of BMPs at watershed scale?
How many and what kind of distributed BMPs are needed to see meaningful impacts to water quantity and quality at watershed scale?
Key innovations/contributions
This project will provide a quantified measure of the collective impact of distributed BMPs on runoff volumes and pollutant loading at a watershed-scale. By testing two separate methods for quantifying these impacts, this work will identify a reliable method that others can use to measure or model the collective benefits of various BMPs.
What does this mean for Minnesota?
This knowledge will assist watershed and stormwater managers to make strategic decisions regarding BMP placement and design. This will lead to more cost-effective stormwater management decisions that more effectively reduce stormwater runoff volumes and prevent surface water pollution. Cleaner water means healthier aquatic habitats, reduced human health risks, and improved recreational opportunities for Minnesota residents.