MN PCA: Stormwater & Rainwater Harvest Case Studies
TL;DR: Stormwater and rainwater harvesting systems demonstrably reduce pollution and conserve water, with real-world examples showcasing successful implementation and cost savings.
- Harvesting systems cut pollution and conserve water.
- Carver County project saves $3,000 annually.
- Systems improve watershed health and reduce runoff.
- Design includes pumps, filters, and smart controls.
- Cost-effective green infrastructure is scalable.
Why it matters: Implementing robust stormwater and rainwater harvesting systems improves local water quality, reduces demand on potable water sources, and creates significant cost savings for communities and businesses.
Do this next: Explore local incentives and regulations for integrating rainwater harvesting into your property or community development plans.
Recommended for: Developers, urban planners, and permaculture practitioners seeking proven methods for sustainable water management and pollution reduction in various settings.
This comprehensive resource from the Minnesota Pollution Control Agency details multiple real-world case studies on stormwater and rainwater harvesting systems designed to improve watershed hydrology, reduce pollutant loading, and promote sustainable water use. Key examples include the Carver County Club West Development in Harvest Estates, Chaska, MN, completed in 2015 by Club West Partners LLC with design by Alliant Engineering. This project features a sophisticated harvest and use system permitted for 22.2 million gallons annually for irrigating lawns in parks, boulevard plantings, and flower beds. The system employs a 1.5-2.0 HP centrifugal stormwater pump to transfer water from two ponds through irrigation controller pedestals, with a rainwater harvester control panel regulating operations. A filter system removes sediment prior to irrigation, and a bypass switch allows municipal water use during low rainfall periods. Modeled benefits include total phosphorus (TP) reductions of up to 4.37 pounds per year and total suspended solids (TSS) reductions of up to 1,503 pounds per year. To date, it has irrigated the site with about 1.5 million gallons of stormwater, yielding $3,000 annual cost savings from reduced potable water use. Another highlighted system is a 4,000-gallon CorGal Water Tank completed in 2012, filled by roof runoff for watering trees, reducing river-bound stormwater, and infiltrating rainwater, with potential future greywater applications in the facility. These cases demonstrate practical implementation of green infrastructure, emphasizing system sizing, pumps, filters, controls, and quantifiable environmental and economic outcomes. The studies provide actionable insights for practitioners, including design features, performance metrics, water quality improvements, and cost efficiencies, making it a high-value reference for replicating similar systems in urban and suburban settings to enhance water resilience and conservation.