The Montgomery County Department of Environmental Protection announced that it had completed the dredging of Gunners Lake, a 20-acre man-made lake located in Germantown.
According to the MCDEP, at the completion of the six-month long dredge process, a DEP contractor has removed approximately 16,500 cubic yards of sediment, the equivalent of about 1,000 truckloads, from the lake and transported it to permitted facilities located out of the county for proper disposal. As a result of the dredging project, the water-quality benefits of the lake are restored which will help protect Seneca Creek, a tributary to the Potomac River and the Chesapeake Bay.
Over time, sediment and debris that affects water quality had accumulated in the lake. Based on the evaluation of the lake and at the urging of the community, the decision was made by DEP to hydraulically dredge, dewater and remove the sediment to improve the lake. Sediment accumulation is a normal process in stormwater ponds and lakes.
The cost of the project was $3 million, which is being funded through the county’s Water Quality Protection Charge, which is included on tax bills.
Amy Stevens, manager of Montgomery County DEP’s Stormwater Facility Maintenance Program told the Germantown Pulse in December of 2014 that “a study of the sediment deck at Gunners Lake and the study revealed that most of the sediment had accumulated in the north end of the lake where the two streams entering the lake are depositing the sediment.”
Stevens said depositing sediment is the normal course of what streams do in stormwater ponds and lakes. However, over time a significant amount of sediment can affect the stormwater function of the lake. “It decreases the amount of stormwater runoff and storage available in the pond and if it is not removed it reduces the lake’s water-quality treatment capacity which is the ability to allow pollutants to settle out, and they settle into the bottom of the lake. It also reduces the stormwater storage which, over time, can lead to downstream flooding.”
“I commend our Department of Environmental Protection for leading this effort and collaborating with the community to effectively and responsibly address the concerns at Gunners Lake,” stated County Executive Ike Leggett. “This is an example of taking care of our natural resources to improve our communities.”
“DEP is pleased to continue working with our residents on large projects such as this. One thousand truckloads of sediment have now been removed from our stream system,” said DEP Director Lisa Feldt. “Restoring the environmental integrity and recreational value of this lake is something we can all be proud of.”
The County, through its MS4 permit, is required to actively reduce stormflow volume and pollutants from entering waterways. Maintenance of these stormwater ponds and lakes, a key component of the County’s integrated stormwater management program to meet MS4 requirements, is critical for clean water and funded solely via the Water Quality Protection Charge.
Gunners Lake was created in 1985 and drains approximately 1,233 acres (nearly 2 square miles) and is owned and operated by the North Lake Village Federation. DEP is responsible for structural maintenance of the lake. Repairs and restoration of the staging and dewatering area at the north end of the lake still remain. Residents of North Lake Village and surrounding communities can expect this final step to be completed in the coming months.
Photo by Germantown Pulse