Carver County WMO partnered with the installation of porous pavement in two locations in Chaska. The firs was with the Lower MN River Watershed District in the fall 2008, behind the County Government Center in the parking lot next to Courthouse Lake. The second was with the City of Chaska in fall 2009, in Veterans Park.
Impervious surfaces (sidewalks, parking lots, etc.) create storm water runoff. Storm water runoff washes pollutants (oil, grease, bacteria, sediments & nutrients) into lakes and rivers and causes erosion and flooding.
Porous pavement slows down storm water runoff and protects our waters by allowing water to drain through the pavement structure where underlying soils filter out potential water pollutants.
How is it different from "normal pavement" ?
Porous pavement mixtures contain less and and other fine materials than traditional mixtures. Space between larger aggregates is not filled. Thus these open pores let water soak through, like a soil would.
Porous pavement reduces both flooding of streets, lakes and rivers and improves water quality by allowing storm water to be filtered before it reaches lakes or rivers.
||Porous pavement at work.
| Rooftop view of the Carver County Gov. Center porous pavement is in two strips along each side of the swale. The rest of the parking lot is standard pavement.
In the summer of 2009, Carver County WMO worked with 4 homeowners on Lake Burandt to install rain gardens. These rain gardens capture storm water runoff (a major contributor to water pollution), and filter the storm water before allowing it to reach Lake Burandt.
Carver County WMO worked with the Carver Soil & Water Conservation District and City of Waconia to design and install the rain gardens. (see below photos)
The summer of 2010, two rain gardens were installed in Minnewashta Park. These rain gardens were designed to capture runoff coming from the parking lots near Shelter #5 and the beach, and filter then filter the runoff before it reaches the lake.
The rain gardens are a result of a grant received by the CCWMO from Minnehaha Creek Watershed District. CCWMO partnered with the Carver County Soil & Water Conservation District, Carver County Parks Dept. and Boy Scout Troop 589 to design and install the rain gardens. These rain gardens will help prevent water quality pollution in Minnewashta Lake.
The photo below shows the rain garden by the beach after installation. The plants will take a year to get established and then fill in and grow taller.
SHORELINE RESTORATION - Brickyard-Clayhole Lake
Carver County WMO received a grant from Minnesota Waters, sponsored by Michelob Golden Draft Light and National Fish and Wildlife Foundation to restore the shoreline of Brickyard-Clayhole Lake in downtown Chaska. This project was completed in August 2010.
Shorelines without vegetation (mowed to shoreline or rip rapped-rocks lining the shoreline) allow lake water to erode shorelines, the damage causes degradation in water quality and loss of shoreline. In addition, geese tend to congregate near mowed or rip rapped shorelines because they are better able to see predators and feel safe.
The project has many benefits including:
-Decreased shoreline erosion.
-Improved water quality, the natural shoreline creates a buffer capturing sediment, nutrients, and bacteria from runoff before it reaches the lake.
-Increased fish and wildlife habitat.
-Increased aesthetic value.
-Decrease in number of geese congregating on shoreline.
-Creation of a natural shoreline demonstration project to be used for education.
Photos below show volunteers during the shoreline planting day on August 2 1st, 2010.