8.C.1. PRSR 09 08 2004 - Laserfiche WebLink

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WHAT IS A RAIN GARDEN? Every time it rains, gallons upon gallons, of polluted runoff flows from our yards, sidewalks, and driveways into Strom sewers or road ditches. This polluted runoff is carried as conduit flow directly into our lakes, rivers, and streams. You don't think about it but around every home and yard their are spots of lutants on the landscape that are waiting to be washed away. Nutrients are found around the yard as lawn fertilizer, grass clippings, and pet waste left on the landscape. Heavy metals and complex organic compounds are deposited in the lawn from roofing materials, metal plating in downspouts, and pesticide applications. Even exposed soil on the landscape can wash down storm sewers causing sedimentation problems in surface waters. The runoff carrying pollutants from our yards may not cause much harm but the pollutants washing into our storm sewers and drainage ditches from all of our yards has a cumulative effect on our water resources. Rain Gardens use native and locally adapted plants to retain and treat stromwater on the landscape before it reaches a storm drain or road ditch. The plants used in Rain Gardens have deep root systems which allows them to retain runoff and filter pollutants in stormwater. Basically, the plants capture and treat runoff from your yard and allows the water to infiltrate into the subsurface rather than having it flow across the landscape as storm- waterwhere it has the ability to pick up additional pollutants. Rain Gardens are placed at the end of downspouts or in low-lying areas of a yard where water collects. The native and i~~ally adapted plants used in these gardens are a to tolerate a mix of dry and wet conditions and even prosper when they are regularly flooded. These gardens are cost effective, too. Rain Gardens require less maintenance than your typical turfgrass. This means less mowing, no watering, and no fertilizer or pesticide applications. They can also provide a great habitat for birds and buttertlies. Rain Gardens areaway of using nature to protect our natural resources. They are attractive landscapes that treat and filter storm- water. ~ ;,;' ~ ain Colter ., , r, ; ;v, ' ~ Downspout -,i~ ,,, ./ r -r „ -, . .. ~, ~~YMI~A~¢/1 l~~~Y~~ Ii ~ ~ i ~ M / }t ~~~ Rain Ga` ~n j Several communities around the nation and in Minnesota are promoting the use of Rain Gardens for the purpose treating urban stormwater. The city of Maplewood, a northern suburb of St. Paul, used Rain Gardens to retrofit a 1950's era subdivision during a street resurfacing and storm sewer construction project. The city used the gardens to downsize storm sewer piping and street gutters in a suburban neighborhood that was under construction. The University of Minnesota estimated a cost saving of $13,000 for the community in the two-block area where the residents installed Rain Garden amenities rather than using the conventional stormwater system approach that uses street gutters and underground piping.' In addition, the neighborhood was interested in protecting a downstream wetland from pollutants associated v urban runoff. The existing piping from the storm sewer system emptied near an existing wetland cam, ~ iplex. The gardens will benefit the wetland area by allowing runoff water to infiltrate into the subsurface rather than directing it towards the sensitive ecosystem. Rain Gardens provided the city of Maplewood with an overall cost saving and assisted the neighborhood with an environmental alternative to reduce pollution 2