Enhancement Program

Sample Completed Enhancement Project

Standish, Route 35 Project

This project was completed as part of MDOT's Surface Water Quality Protection Program (SWQPP) and falls under the 'Environmental' category.  The Portland Water District (PWD) nominated this site on Route 35 in the Sebago Lake watershed.  Sebago Lake supports many recreational uses including warm and cold water fisheries, and serves as the public water supply for ten communities including the City of Portland.  An MDOT culvert was discharging untreated highway runoff to the lake approximately 500' from the water supply intakes.  The project goal was to treat the highway runoff before it reached the lake.

Under this collaborative effort, a catch basin, a 3000-gallon concrete holding tank, and two water treatment units were installed.  The catch basin captures winter sand and other debris.  From the catch basin, the water flows to the concrete tank, where it is slowly metered to the treatment units.  Each of the two treatment units contains wetland plants, which remove nutrients and other pollutants.  From here, the treated water is discharged down an existing riprap downspout to the lake.

The project received $47,365 in Federal Transportation Enhancement funding for a total project cost of $59,000.