Reducing Stormwater Impacts in Vergennes

Improving stormwater treatment in this Vergennes neighborhood with LCC’s help. Photo by Otter Creek Engineering.

Developed land is a significant source of phosphorus loading to Lake Champlain. Measures to reduce loading include revisions to the Vermont stormwater manual, improved management of roads and construction sites, and increased use of low-impact development practices. But to really get a handle on phosphorus-loading from developed land we will also have to address areas that have already been built. To that end, LCC recently completed a project to design a retrofit for a stormwater pond in Vergennes. The pond in question was not designed to remove phosphorus from stormwater. It was originally designed in 1987 to ease potential flooding from large storms as per the regulations of the time, but it can be retrofitted to also provide water quality treatment. 

The pond is one of many that serve residential subdivisions whose permits were issued to the original developer but never renewed leaving no responsible party to maintain and update the structures.  The City of Vergennes adopted the orphaned system. It was identified as needing remediation by a stormwater mapping project conducted by the Vermont Department of Environmental Conservation (VT DEC) and in the City of Vergennes Municipal Plan. 

LCC worked with the City of Vergennes and Otter Creek Engineering on the project which was funded by and Ecosystem Restoration Grant from VT DEC. Otter Creek Engineering provided design specifications and a cost estimate for the pond. The pond provides treatment for 6.33 acres of developed land and nearly 170,000 gallons of stormwater. LCC and Vergennes will now need to work with the land-owner on whose property the pond is located to secure funding for construction from VT DEC. The City is in communication with the landowner on whose property the pond is located and we are working with them to identify funding sources for construction of the new pond. 

“We greatly appreciate the assistance of LCC in getting grant funding to address this pressing problem in Vergennes,” said City Manager Mel Hawley.