Maine Mall Gravel Wetland

Maine Mall Gravel Wetland

 

An existing detention basin adjacent to the Maine Mall parking lot was retrofitted into a gravel wetland. Gravel wetlands remove pollutants much better than other conventional designs. Pollutants are removed through a range of pathways, including biological and microbial activity on the surface of the gravel and in the underlying soils, pollutant uptake from wetland plants, and sediment removal from settling. The new system was installed in 2015 at a cost of $618,850. The project meets watershed management goals by:

  • Treating 33.9 acres of impervious surface, primarily parking lots. An additional 1.16 acres of impervious parking lot area was redirected into the detention system.
  • Cooling the runoff before it enters Long Creek.
  • Reducing surges of runoff from entering Long Creek during rain events. Instead, runoff moves through the systems and slowly enters the stream. 
 
 

Supporting Documents and Resources

Design Drawings