Location: Southeast corner of CR12/17 Intersection
Project Type: Capital Projects
Project Status: Complete
Current Status: Ongoing maintenance
Property Information
Size: ~8 acres
Ownership: City of Prior Lake
About this Project:
Project Goals:
- Stores Excess Water by Restoring Wetlands
- Slows the Stormwater Down
- Reduces Phosphorus Entering Spring Lake
The CR12/17 Wetland Restoration Project is an innovative stormwater treatment project intended to improve water quality in Spring Lake. The project enhances flood control and capture phosphorus and sediment before they reach Spring Lake and other downstream water bodies. It treats runoff from two highways, city roads as well as an upstream 60 acre agricultural area.
Restoration Plans
The project consists of one stormwater pond and three wetland basins of varying depths, each with its own role in removing phosphorus. These restored wetland basins provide additional storage capacity for runoff and slow travel of stormwater. Adjustable stop logs allow the water levels in each pond to be changed to increase or decrease holding time as needed.
The wetlands are surrounded by native prairie plants. Their deep roots help clean the water before it reaches the lake and the plants provide important habitat to wildlife and food for pollinators.
Iron Enhanced Sand Filters in Pond 2 use sand mixed with iron filings to remove dissolved phosphorus from the water, preventing it from eventually making its way into the lake.
Other features of this site include, a seasonally operational fish barrier, walking paths, and an interpretive sign.
The District will continue to monitor and maintain the vegetation around the wetlands until it has been successfully established.
Anticipated Outcomes
Three wetland and treatment basins and an iron sand filter system were installed in addition to a small trail system. The project stores approximately 62 acre feet of stormwater per year. In 2014, extensive rains in the Spring caused regional flooding and the wetlands provided much needed stormwater storage. In addition, the settling of particulates in the wetland as well as removal of phosphorus from the iron sand filters results in approximately 60 lb/year of TP reduction. The three Agri Drain Outlet structures are retrofitted with vertical bar grates to limit the access of common carp into the project area.
Informational Materials
Fact Sheet: Upper Prior Lake – Targeted Retrofits & Enhancements
Fact Sheet: Clean Water Story- Upper Watershed Volume Reduction
News and Related Articles
Stay updated with this project through the PLSLWD News and Events Blog.
Partners
City of Prior Lake
Public Facilities Authority
Scott County SWCD
Board of Water and Soil Resources
Clean Water, Land and Legacy