Ralph Engelstad Arena Raingarden
The Ralph Engelstad Arena in Thief River Falls is the premier high school hockey arena in the State of Minnesota. The Arena fills two city blocks and is covered by 85-90% impervious (hard) surface. Rainfall events completely inundate roads and sidewalks, overloading the stormsewer system. Larger events cause water to stand high enough to reach the front steps to the Arena. Roof runoff produces large amounts of water running from the downspouts. Runoff has made sod establishment on the grounds difficult. Washouts have developed carrying sediment to the stormsewer. During spring melt, runoff crosses the sidewalks and freezes at night causing a slippery and hazardous conditions.By implementing multiple raingardens, runoff water will be stored on site to control a majority of the runoff. Not only will water quantity be reduced, but water quality of the stormwater will be improved coming off the site.This project will have an immediate benefit, reducing pollutants associated with urban runoff such as phosphorus, sediment and nitrogen. The proposed raingardens will hold approximately 3.05 acre/ft of water during a one inch rainfall event. Runoff water will be slowly released either into soil or into the stormsewer through underground tile.
Nicole Clapp
(c) $3,000,000 the first year and $3,000,000 the second year are for nonpoint source pollution reduction and restoration grants to watershed districts, watershed management organizations, counties, and soil and water conservation districts for grants in addition to grants available under paragraphs (a) and (b) to keep water on the land and to protect, enhance, and restore water quality in lakes, rivers, and streams, and to protect groundwater and drinking water. The projects must be of long-lasting public benefit, include a local match, and be consistent with TMDL implementation plans or local water management plans. Up to five percent may be used for administering the grants (2011 - Clean Water Assistance)
This project will have an immediate benefit, reducing pollutants associated with urban runoff such as phosphorus, sediment and nitrogen. The proposed raingardens will hold approximately 3.05 acre/ft of water during a one inch rainfall event. Runoff water will be slowly released either into soil or into the stormsewer through underground tile.
Three raingardens were constructed during the summer of 2014. These raingardens reduce 3 tons of sediment, 20 pounds of phosphorus, 18 pounds of nitrogen, and 0.37 acre-feet of volume from entering the Red Lake River annually.