By Robert D. Utter
NORTH STONINGTON – The town’s three recreational lakes - Wyassup Lake, Billings Lake, and Blue Lake - are infested with a few species of invasive weeds.
They have been for years, and that makes them the same as almost every lake in the Northeast. The two worst culprits are variable milfoil (Myriophyllum heterophyllum) and fanwort, (Cabomba caroliniana).
Each year, the town spends $15,000 to help suppress these weeds, although it’s a drop in the bucket compared to what it would take to eradicate the weeds from the lakes.
At 101 aces, Wyassup is the largest of the town’s lakes, with an average depth of 10 feet and maximum depth of 24 feet.
Billings Lake is about 97 acres and, at an average 14 feet and a maximum of 33 feet, the deepest of the three. The $5,000 from the town is used to treat about 2 square acres along the shore with a chemical called diquat bromide, knocking out the milfoil and fanwort by the lakeside homes and access points.
William Bridgewater of the Billings Lake Association said the diquat is effective for a single season, but it does not kill the roots, so by the time the next summer comes around, it is all back.
Billings Lake contracts with SOLitude Lake Management of Massachusetts to do the spraying there in late June-early July each year. The company has let Bridgewater know that it would cost about $100,000 to treat the entire lake but “the money’s not there,” he said.
As the smallest of them, Blue Lake (aka Anderson Pond) covers about 57 acres. It’s shallow, with a 5-foot average depth and a deepest point of only 8 feet. That means that sunlight has a particularly easy time of keeping invasive plant life healthy.
The Blue Lake Taxing District spent $6,500 last year to keep 5 to 6 acres out from the boat ramp clear, said William Hixson. Many people around Blue Lake are concerned about the use of herbicides, he said, so the work is pretty targeted. “We try to do as little as possible.”
With association taxes going for insurance to cover the lake’s dam and the association’s roads, the extra $1,500 over and above the town’s $5,000 grant is raised from private donations, Hixson said.
The diquat is applied to the surface of the water. When it makes contact with the targeted species, it causes desiccation and defoliation within 72 hours. The treatment process requires a state permit.