Quick Facts:

Year built: 2014

Raingarden planted by Elementary students.

Supports Lambert Creek and East Vadnais Lake by providing runoff storage and reducing runoff rates.

Funding:

This project was funded by VLAWMO’s Community Blue grant program, which harnessed funding from Minnesota Clean Water Funds.

Reason for Project:

Staff and parent leaders at the Vadnais Heights Elementary pioneered the Bear’s Backyard Raingarden to support the school’s science curriculum and serve as an educational tool to the broader school community. At a high traffic location near the playground and basketball court, the raingarden provides a scenic feature complete with birds and pollinators, and demonstrates how to make a positive impact on our water resources on a community level.

Construction:

The raingarden basin is 600 sq ft.

It takes stormwater runoff from the school gymnasium roof, south parking lot, the southern edge of the schoolyard, and basketball court. The raingarden directs water from the parking lot to the adjacent wetland. The excavated material was used to create a berm to aid in temporarily holding stormwater runoff, allowing it to infiltrate into shallow groundwater. A layer of sand/compost mix was used as a soil amendment to promote infiltration.

The raingarden inlet features a border of trap rock to slow down incoming runoff flowing downhill from the parking lot. The raingarden also includes an overflow feature, directing water straight to the wetland when the water level reaches above 1 ft depth. This helps ensure the raingarden can infiltrate and dry out in under 48 hours.

The raingarden was planted by elementary students. Ongoing maintenance occurs through a community effort between Elementary school classes, parent volunteers, and nearby congregations.

Native plants in the raingarden include: Butterfly milkweed, compass plant, Joe-pye weed, prairie dock, purple coneflower, prairie smoke, and common wood sedge.

Results:

The raingarden supports stormwater runoff that makes its way into the Bear’s Backyard wetland, which is adjacent to Lambert Creek. Both the wetland and Lambert Creek drain into East Vadnais Lake. The raingarden acts as a buffer to reduce stress (such as sediment and nutrient loading) on the receiving wetland, and provides valuable water storage and infiltration upstream of Lambert Creek. The raingarden and projects like it help support the health, function, and performance of the Lambert Creek ditch drainage system.

Each year, the raingarden is estimated to capture and treat:

• 15,395 gallons of stormwater runoff
• 40.1 lbs of sediment
• .2 lbs of phosphorus (A little phosphorus reduction goes a long way - 1 lb of phosphorus can create up to 500 lbs of algae)

Project Image Gallery