Mohegan Lake Improvement District Attacks Plant Infestation

The Mohegan Lake Improvement District is fighting a highly invasive water plant that threatens the historic resort.

The plant, called a water chestnut, grows in bodies of fresh water. Water chestnuts can form dense floating mats, severely limiting light -- a key element of aquatic ecosystems. The plant also reduces oxygen levels, which may increase the potential for fish kills. It competes with native vegetation and is of little value to waterfowl.

Water chestnut infestations limit boating, fishing, swimming and other recreational activities. Further, to add injury to insult, its sharp fruits (called nutlets) can cause painful wounds if stepped on.

Improvement District board member Ken Belfer, whose daughter gave a presentation at the Town Board's July meeting about the said the residents had just begun fighting back. 

"We've had an effort that started last year to eradicate the water chestnut and it involves a lot of hand work," he said. "We go out in boats and go along the shoreline and hand pull them. This work needs to be completed by this time of the year, because once the nutlets mature they fall off and begin to grow new plants. If you try to pull the plant when the nutlets are "loose" then you can spread the growth instead of stopping it."

Belfer said they expect the problem, if properly handled, could be eliminated within five years.

There are a few things in place to combat this and other problems growing on the lake.

The first is an aeration system.

A series of sheds have been strategically positioned around the lake. Inside each shed is an aeration unit. These units are basically air compressors with tubes that go deep underground and under the lake.

Pumping air from the bottom of the lake to the the top prevents algae (a common lake problem) from growing and provides a healthier environment for life in the lake.

The second system is a weeding operation. This is just as it sounds, pulling up any plants that are growing on the water that are deemed hazardous to the lake's health.  Some is done by hand and much by the district's weed harvester, an orange pontoon boat fitted with a weed cutting/collecting machine.

The Mohegan Lake Improvement District was established in 1975, by joint action of the Town Boards of Yorktown and Cortlandt. The District includes all properties having "lake rights" to this private lake. It's hardly "private," however - with some 1,500 households now comprising the District. Also, the town of Yorktown owns several parcels called "dock lots" bought up to prevent waterfront development.

Currently the District raises about $48,000 a year in taxes (roughly $30 a household) to manage the lake. The District is managed by a group of volunteers, who meet the second Wednesday each month during much of the year.

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