MIDDLETOWN — Township officials will continue their multipronged attack on invasive vegetation at Shadow Lake this summer, removing plant life from a 4-acre section of the lake and treating the perimeter with herbicide.
The program began last summer when the township contracted a hydro-raking company to pull aquatic weeds such as water chestnut and Eurasian water milfoil from the westernmost portion of the 85-acre lake, near Stevenson Park.
Township Engineer Joseph “Ted” Maloney said that first phase, which also included an herbicide treatment and a price tag of about $42,000, was a definite success.
“It’s amazing, when you look at the before and after pictures,” he said after the Township Committee’s May 5 workshop meeting.
The committee has gone out to bid for the second phase of the project, which is designed to improve water quality at the lake and free up access for boaters, swimmers and other recreational users.
The hydro-rake machine, which resembles a backhoe with a large rake attachment affixed to a paddleboat, pulls the vegetation out by the root and deposits it on the shore.
Projected to begin in June, this phase will address a similarly sized portion to the east of last year’s work.
Township officials are also planning to do two herbicidal treatments this year — in June and September — to help kill off the vegetation and prevent new plants from growing.
The total projected cost for the work is about $60,000, Maloney said.
While the herbicide is environmentally safe and has been approved by the state Department of Environmental Protection (DEP), Maloney said nearby residents should avoid drawing from the lake to water their lawns or gardens for about 24 hours after the treatment.
“It’s an herbicide, so obviously it would kill the grass,” he said.
Officials said they would post details about the work to the township website after a definite schedule is finalized.
The treatment and hydro-raking program are expected to continue in future years and address multiple sections of the lake, but Maloney said township officials will continue to monitor the results on an annual basis.
While the work is expected to make Shadow Lake more accessible, township officials said it will not have an impact on accumulated silt levels and the longstanding need for dredging.
Despite extensive planning and multiple proposals throughout the last decade, Committeeman Anthony Fiore said it is still too expensive to consider dredging even a portion of the lake.
“It is just cost-prohibitive,” he said.
Residents surrounding the lake have raised concerns for years about the rising levels of silt in Shadow Lake, pushing the township to invest in a comprehensive dredging effort.
However, due to naturally occurring arsenic in the dredge material, the DEP has prohibited the township from dumping it locally. Instead, the material would have to be dried and shipped to a Brownfield site in Sayreville.
The shipping costs simply make the project unaffordable, Fiore said.
In 2012, the committee solicited two rounds of bids for dredging about one-third of the lake and the shipment of the material. The lowest bid was nearly $4.8 million, about $2 million more than township officials were prepared to spend.
The committee voted to reject all bids for the project, and no new alternatives have not yet been proposed.