On the Quality of Hook Pond

In an effort to improve the water quality of Hook Pond, which the state’s Department of Environmental Conservation has listed as impaired, the Village of East Hampton is planning projects to reduce stormwater runoff and contamination from aging or malfunctioning septic systems.

The pond, in which concentrations of nitrogen typically exceed Environmental Protection Agency criteria, is a collection basin for the 2,369-acre watershed that includes the Main Street and North Main Street commercial districts, the 207-acre Maidstone Club, and residential areas.

The remediation plans result from a study of Hook Pond commissioned by the village following the completion last year of a Wastewater Management Plan for East Hampton Town by the environmental consulting and engineering firm Lombardo Associates. The study confirmed that nitrogen and phosphorus  had damaged the pond’s water quality.

With a combined cost of $92,750, the projects are to be implemented either in the fall or the spring of 2016. The village will shoulder half the cost, with the other half provided by the Suffolk County Water Quality Protection and Restoration Program. Legislator Jay Schneiderman sponsored the projects in the County Legislature.

In the first project, an existing 250-foot-long channel that conveys stormwater runoff from the North Main Street commercial area to Hook Pond will be converted to a half-acre wetland and drainage course, or bioswale, intended to trap and filter stormwater, while reducing the flow into the pond by increasing the time stormwater is retained in the bioswale.

Eleven stormwater filters to help remove pollutants will be installed in existing storm basins in the vicinity, including at and near Pantigo Road, Hook Mill Road, Accabonac Road, Main Street, and North Main Street.

In the second project, a quarter-acre of the village green, where stormwater collects from Route 27, Route 114, and the Main Street commercial district and overflows into Town Pond (which is connected by culvert to a feeder stream of Hook Pond), will be excavated to a depth of 12 to 18 inches and replanted.  The shallow swales there will promote filtering and reduce the intensity of stormwater flow to the pond. Eight stormwater filters will be installed in existing storm basins at the green.

In both projects, the removal of silt and debris from the water flow is expected to assist in water-quality remediation.

In the village’s application for a grant from the county program, Drew Bennett, a consulting engineer, estimated that the bioswales will result in a 40 to 60-percent point-of-contact reduction in nitrogen and phophorus. Wastewater, contaminated by waste from warm-blooded animals, especially waterfowl, is cited as a primary source of excess nitrogen in water bodies.

 In addition to Hook Pond, Georgica Pond in East Hampton and Fort Pond in Montauk are impaired by discharges of phosphorus from stormwater and aging or malfunctioning septic systems, according to Lombardo Associates.

The town’s Wastewater Management Plan also recommends establishing and enforcing regulations on the use of fertilizers. The East Hampton Town Trustees, who oversee many of the town’s beaches, waterways, and bottomlands on the behalf of the public and are collaborating with the village on the Hook Pond effort, have spoken in favor of such regulation.