A proposed town house development along a portion of the Hackensack River that leads to the Oradell Reservoir is drawing concerns from environmentalists, who worry that it will increase runoff into a water source for 800,000 people.

The 249-unit project would be built on a portion of the Edgewood Country Club in River Vale and increase the amount of asphalt, concrete and other impervious surfaces by 23 acres.

The developer, Woodmont Properties of Fairfield, said it is installing a large stormwater system to contain runoff. In documents filed with the borough, Woodmont says the project is “a moderate to low-impact development that will minimally increase pollution, traffic, noise, or degrade surface water quality.”

But that is not reassuring to groups that have spent years preserving thousands of acres along the upper Hackensack River.

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"It's a high-density development in exactly the wrong spot," said Lori Charkey, director of Bergen SWAN, an advocacy group that fought to save 3,500 acres in the region from development.

Edgewood is just southwest of the Lake Tappan reservoir. The Hackensack River meanders through several towns to the Oradell Reservoir, where the Suez water company filters water before sending it to large swaths of Bergen and Hudson counties.

Suez executives are still evaluating the proposal, but they said Thursday that they hope it is done in a responsible manner to limit the impact on its water system.

"We would hope that a development with new structures by the Hackensack River would include permeable surfaces that would allow for the absorption of stormwater," said Debra Vial, a Suez spokeswoman. "This would help reduce the potential for flooding."

This map shows the Edgewood Country Club in River Vale, New Jersey, but is erroneously displaying a Pittsburgh address.

The project calls for 225 market-rate town houses and condominiums for sale and 24 affordable-housing rental units in a three-story building in a 50-acre section of the 187-acre site. The country club facilities and 18-hole golf course will remain.

Two brooks run through the property — the Hillsdale Brook on the western edge and the River Vale Brook on the eastern end, flowing into the Hackensack River. The waterways have some of the highest protections in the state, and the developers say their plan won’t infringe on a mandated 300-foot vegetation buffer around the brooks.

The plan has already generated opposition from some neighbors concerned about traffic and flooding.

But Woodmont executives said concerns about runoff are not founded.

The project calls for three large stormwater basins to be built on the western edge of the property, away from the River Vale Brook and the Hackensack River, would release water to the nearby Holdrum Brook at a lower rate than it currently does. Some of the water would be reused to irrigate the golf course.

"New Jersey has some of the most stringent stormwater regulations in the industry, and we're following them very closely," said Steve Santola, executive vice president and general counsel for Woodmont. "If you look at our stormwater report, the system that we're proposing is better than what's there currently."

The plan continues a trend in North Jersey of golf courses being converted to housing in an area where open space is at a premium.

Environmentalists are concerned that runoff would be especially bad during construction, similar to muddy runoff that has been going into an Upper Saddle River brook for more than a year from a Toll Brothers housing project.

Woodmont would cut down 287 trees, but said there would be no clearings in primary wetlands areas near the brooks and river. A silt fence will be placed around the construction site to limit runoff, according to an environmental report submitted by Woodmont's contractors.

Bergen SWAN, the Hackensack Riverkeeper and Bergen County Audubon said the portion of the golf course would be a perfect plot of land to preserve with open space funds.

But Hackensack Riverkeeper Bill Sheehan — a longtime member of the Bergen County open space committee — said it would be very difficult to preserve the land because the proposal is well underway, with hearings before the River Vale Joint Planning Board.

Letters to apply for Bergen County open space funds are due March 19.

“The problem is we find out about these projects late in the game, when they’re already going through the planning process,” Sheehan said. “This is a good example of why we have an open space trust fund. But these are properties that should have never been developed in the first place.”

Email: fallon@northjersey.com

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