The waters of New Rochelle Harbor and Long Island Sound surround Glen Island Park. The island once consisted of five smaller islands. By filling in the water and wetlands around the islands in the 1920s, a single, 105-acre island was created. The park features the Glen Island Harbour Club, a county-owned, privately operated catering facility, as well as picnic areas, beach and bathhouse, refreshments facility, playground, and areas for walking and fishing. The island is the second-most used Westchester County-owned park, requiring large parking lots to accommodate visitors.
In the past, stormwater runoff washing over the parking lots scrubbed away oil and grease, sand and sediment, metals, nutrients, and other pollutants and sent them directly into the surrounding estuarine waters in a solution known as polluted stormwater.
A watershed management plan, completed in 1997 on behalf of five municipalities by staff of the Department of Planning, targeted the park area as a potential stormwater “retrofit” site. In other words, it was a polluted stormwater source that could be overhauled to improve its water treatment capabilities. An advanced technology solution was sought to treat the polluted stormwater before it enters the harbor and Sound. The technology would have to be able to remove a significant amount of several pollutants, not take up much land area in the confines of an island park, withstand the sometimes harsh conditions experienced at a coastal site, and offer a visible element that could be used for educational and demonstration purposes.
Through its research, the Department decided to pursue the technology offered by StormTreat System, whose stormwater management units were installed at only one other location in New York State. Having successfully secured a state grant and county funding, the Department, with cooperation from the departments of Public Works and Parks, Recreation and Conservation, hired a consultant and contractor to design and install 16 units at Glen Island. These were designed to treat polluted stormwater running off more than seven acres of pavement from the park’s two largest parking lots.
The project involved the installation of special catch basins and underground pipes to detain stormwater, two new outfall pipes, and 16 StormTreat System units. A StormTreat System unit is a pre-fabricated, cylindrical “tub” installed flush with the ground. The bulk of the “tub” is below-ground. It consists of a series of underground sedimentation chambers with skimmers and an at-grade gravel filter, which serves as a substrate for wetland plants. Stormwater runoff from the impervious parking lot surfaces is collected in catch basins, routed through the detention pipes, and then distributed amongst the StormTreat units. After being treated by this system, the stormwater could either pass through a stone reservoir around the units into the surrounding soil or be discharged through a pipe to the harbor.
To View The Site: The site is at Glen Island Park in the City of New Rochelle. From the north take the Hutchinson River Parkway to the Sanford Boulevard exit. At exit, turn right. At second traffic light, turn right onto Pelhamdale Avenue. Follow to the end and make a left onto Pelham Road. At first traffic make a right to enter Glen Island Park. OR New England Thruway (Interstate 95) south to Exit 15 (Route 1). Off exit make left onto Route 1 [Post Road]. At second light, make a right onto Weyman Avenue. Follow Weyman Avenue into Glen Island Park.