The Great Pond Foundation recently hosted a Get-to-Know Nessie festival on Edgartown Great Pond. Underwritten by an anonymous patron, this event gave donors and neighbors a chance to see firsthand the portable dredge that has been acquired to assist the town of Edgartown with its efforts to preserve Edgartown Great Pond.

While Nessie has already operated twice in the pond, and will do so again during the winter months, few people have had an opportunity to see her. Nessie is used to cut a channel through the shallow sandbars inside the barrier beach of Edgartown Great Pond so that openings to the sea will be more effective in exchanging high-nitrogen pond water with fresh ocean water. Neighbors around the pond and at the barrier beach were given an opportunity to visit her spaceship-like control panel while she toured a show-and-tell program. Anne Mazar, a seasonal resident, commented: “It was helpful to actually touch and feel the dredge and discuss some of the other projects currently underway on the pond.”

This dredge is unique. She needs only 20 inches of water to operate, making her ideal for the shallow waters of the pond. She can be launched from a specialized boat trailer, increasing efficiency in putting in and taking out of the pond. The entire launch process does not require a crane or any other heavy equipment. Nessie is operated by Tracy Benware and Tony Gramkowski of Aquamarine, a company owned and operated by Steve Ewing. Steve has spent his life operating heavy equipment in Vineyard waters and has served this Island as a leader in environmental management.

The Massachusetts Estuaries Project is a comprehensive, multi-year study to assess the rapidly declining health of bays, harbors, and ponds in Southeastern Massachusetts. One of the first reports completed was of the Edgartown Great Pond, found to be under stress and requiring immediate action if it is to be saved. An increasing volume of nutrients, such as phosphorus and nitrogen, is affecting water quality and encouraging invasive weed and algal growth. This can destroy productive shellfish beds, damage the diverse habitat and restrict recreational uses now provided by the pond. The project has recommended specific remedial actions for the town to respond to this serious threat.

One is to increase the number of homes in the watershed connected to the municipal wastewater treatment facility. Another is more regular and effective openings of the pond to the sea. Four times each year, under the direction of shellfish constable and biologist Paul Bagnall, a cut is made through the barrier beach, opening the pond to the sea and exchanging high-nitrogen pond water with fresh ocean water. During each opening, a large volume of sand is deposited into the pond, making successive openings less effective. Dredging can provide an extremely effective solution to this problem. In March, Nessie operated for two weeks, dredging a channel through a large delta sandbar that had built up in recent years, pumping sand out and renourishing the barrier beach. The following month, the pond was opened and remained so for over three weeks — the longest in almost 20 years. Enhanced openings have already had a positive effect on water quality, particularly during this unusually hot summer when many ponds throughout the Cape and Islands suffered high bacterial concentrations and large algal mats. Mr. Bagnall found it remarkable that the water quality remained good in the pond throughout the hot, sunny summer.

In these difficult economic times, the Great Pond Foundation raised almost $800,000 from property owners around the pond to acquire Nessie and partner with the town in protecting the pond. While dredging is extremely important, it is only one of many tools being used to improve the water quality. For example, the foundation is working with the Nature Conservancy and private property owners to manage nonnative, invasive phragmites infesting areas of the shoreline. Foundation interns have provided valuable assistance to the highly successful oyster restoration project managed by the Martha’s Vineyard Shellfish Group. Oysters are an extraordinary resource in keeping the pond healthy, as each individual oyster can cleanse up to 15 gallons of water every day. A circulation study is being conducted to identify additional areas within the pond where dredging could improve circulation and water quality, particularly in upper coves. Research and testing is being done on harvesting algae and preventing recurrence of the frightening massive algae invasion that occurred during the summer of 2008. Since completion in 1996 of the modern wastewater treatment facility in Edgartown, there has been concern and uncertainty about underground effluent from the old plant moving toward the pond.

Monitoring and testing is now being done on a regular basis to determine the size and location of this plume.

This all adds up to a full plate, and the foundation is now passing the hat to meet an operating budget for this year of $320,000. The goal is 100 per cent participation by riparian owners, and everyone who cares about this important and beautiful resource is encouraged to make a tax-deductible contribution. To learn more about the foundation or to make a donation, please visit greatpondfoundation.org or send your contribution to: Great Pond Foundation, P.O. Box 2005, Edgartown, MA 02539.