The swimming beach at Lake Iroquois is an important resource for the four towns that make up the Lake Iroquois Recreation District (LIRD) and other Vermont residents. A project was recently funded through the Vermont Department of Environmental Conservation’s Ecosystem Restoration grants program for ecological landscape design, erosion control and stormwater management to protect the beach. The project consisted of the construction of a Bio-Retention Stormwater Treatment and Ground Water Diversion Facility to minimize stormwater runoff and associated erosion. It also provided plantings and restoration work along the shoreline to help further mitigate any erosion activity caused by the action of the lake itself.
Sand is a vital component of any beach. But each significant rainfall sends gushing water across the parking lot and the beach. This torrent of water pushes road gravel and beach sand into the lake and carves deep trenches in the land left behind. This erosion adds phosphorus to the lake from the finer particles in the sand and increases cloudiness in the lake, which adversely impacts aquatic habitat. On average about 16 yards of sand is added each season. By some accounts this added as much as 6.4 kg of phosphorus (P) to the lake from beach erosion itself. This number only takes into account the amount of phosphorus reduced by keeping the beach sand from entering the lake and does not account for the amount of phosphorus and other nutrients that are eliminated by the Bio-Retention System or the amount reduced by the shoreline planting.
The completed project will help play a role in improving the water quality of the lake and allow the District to continue to provide a valuable resource for recreational use for years to come. The District is thankful for everyone who helped make this Project a success; the Agency of Natural Resources for their guidance, KAS Engineering for putting together the plan and design, and, the Lake Iroquois Association for both local knowledge and in monetary contributions.
The project was completed for the Lake Iroquois Recreation District by Dirt Tech LLC in October of 2015. The project was completed on time and on budget during the low water time for the lake and the down time for the recreation district.