JENNIFER GUSTAVSON PHOTO | Pine Barrens Society head Richard Amper reads from the Suffolk County Drinking Water Protection Program, which states the law "may only be amended, modified, repealed or altered by an enactment of an appropriate Charter Law subject to mandatory referendum."

Environmentalists are charging county lawmakers “illegally raided” funds slated for open space preservation and drinking water protection to balance next year’s budget without getting voter approval in the form of a mandatory referendum.

Pine Barrens Society head Richard Amper held a press conference Thursday at the steps of the Suffolk County Legislature’s offices — where he was joined by other environmentalists — announcing the groups are suing the county over its actions.

Mr. Amper, who is the executive director of the nonprofit Riverhead-based Long Island Pine Barrens Society, said his group has filed a lawsuit to reverse a bill approved last month by the Legislature and County Executive Steve Levy that allows the county to take 37.5 percent of surpluses over $140 million from the Suffolk County Drinking Water Protection Program.

That money would be taken from a budget line in the open space program slated for sewer tax rate stabilization to help plug the county’s $150 million overall budget gap. Other lines include land acquisition and water quality and land stewardship.

Mr. Amper said the county’s move was illegal because the program, created in 1987 to safeguard drinking water through purchasing land and preventing development, “may only be amended, modified, repealed or altered by an enactment of an appropriate Charter Law subject to mandatory referendum.

“Voters have approved hundreds of millions of dollars to protect their drinking water and Suffolk government raided it,” Mr. Amper said at the Hauppauge press event. “We want it back.”

But Mr. Levy responded in a statement that both the county attorney and the counsel to the Legislature agreed that a mandatory referendum was not required. In addition, Mr. Levy, who described Mr. Amper as a “gadfly” who doesn’t represent all environmentalists, said the bill was co-authored by environmental groups Citizen’s Campaign for the Environment and the Group for the East End.

County officials said the bill also includes applying 62.5 percent of the surplus over that $140 million number to the budget for sewer capital projects, such as septic tank upgrades near impaired bodies of water.

The rest could go toward helping balance the budget.

“Environmentalists and elected officials agreed that it was foolish to leave hundreds of millions of dollars sitting idle, in reserve, when we could be using it to protect our water supply and grow our economy through sewer districts while reducing our debt and stabilizing taxes,” Mr. Levy said. “The reserves are those monies over and above the amount secured to ensure stabilized rates for all sewer district residents through the year 2030.”

The legislation passed last month reads that the fund’s surplus will exceed $154 million by year’s end. The money is raised by charging a quarter-penny sales tax on goods and services in Suffolk County.

A spokeswoman for the county Legislature said a more accurate figure is $157 million.

Based on the legislation, that would make $17 million total available, though 62.5 percent, or $10.6 million, could only be used for sewer-related capital projects.

The remaining $6.4 million could be transferred elsewhere to help balance the budget.

Jennifer Juengst of the Long Island Environmental Voters Forum, another litigant in the case against the county, said Thursday the “voters have been defrauded” through the government’s actions.

“We urged voters to support the Drinking Water Protection Program most recently in a 2007 referendum, so it’s our responsibility to prevent elected officials from committing voter fraud by ripping taxpayers off,” she said.

The lawsuit was filed September 15 in State Supreme Court in Riverhead.

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