Aquatic vegetation has returned to cover much of the surface of Fawn Lake.
And according to the town’s conservation administrator, that’s not a surprise, irrespective of the 2020 dredging of the lake floor.
“What is seen on the lake now is what would be expected, given the project and other prevailing conditions over the last couple of years,” said Jeffrey Summers this week in an email. “While the expectation was that we would have more open water than what we see now, unfortunately when trying to manage the environment the end results of any project can be hard to predict.”
Summers explained, “The initial project was to dredge 60 percent of the lake to remove accumulated sediment and the rhizomes of aquatic vegetation such as water lilies. This was to open up a portion of the lake surface for recreational use such as paddling.”
“The reason for leaving 40 percent of the lake untouched was to allow for a more diverse ecology within the lake,” he continued. “A shallow lake environment wants to grow things within it, whether in the form of plant vegetation from the bottom or in the form of algae and other micro species such as duckweed and watermeal.”
During the dredging process, Summers pointed out, “a shelf on the lake bottom was discovered. This runs generally north to south in the middle of the lake and because of the shallower water here, light can more easily penetrate to the bottom and propagate vegetation growth in the area.”
“Water lilies and some water shield were noted in this area and the DPW is likely going to propose a targeted treatment of aquatic herbicide next spring to help keep this growth at bay.”
“These are small flowering plants which float about in the water and sometimes give the appearance of an algae bloom when they are densely packed. One or the other is usually what is observed within a typical shallow lake and the latter are common in late summer.”
Summers noted that “another factor contributing to the growth of water lilies is this summer’s drought, where lower water levels again allowed for easier light penetration to the lake bottom.”
The dredging took place before Summers joined the municipal staff. He said he gleaned background information from Adrienne St. John, retired DPW engineer, and Bob Hartzel from the project’s technical consultants, CEI. Both were closely involved with the project.
“Part of the project was also to facilitate dam and drainage improvements on the Springs Road side of the lake,” Summers mentioned.