May 20, 2016 By Jennifer Barrios   jennifer.barrios@newsday.com

Outfall tide pumps at the Bay Park Sewage Treatment Plant. Officials may want to send effluent from the facility to the Cedar Creek plant. (Credit: Charles Eckert)

Effluent from Nassau’s Sandy-damaged Bay Park sewage-treatment plant could be diverted to an ocean-outfall pipe at the county’s Cedar Creek plant in Wantagh through an unused, historic aqueduct along Sunrise Highway, under a proposal Nassau officials plan to announce Friday.

The new proposal is estimated to cost far less than the estimated $450 million the county has been struggling to find to build an ocean-outfall pipe to send the effluent from Bay Park into the Atlantic Ocean instead of the nitrogen-choked Western Bays.

“This will save the Western Bays,” said Adrienne Esposito, executive director of Citizens Campaign for the Environment. “Unequivocally, without a doubt. It’s the best environmental news we’ve gotten in two decades.”

Under the proposal, County Executive Edward Mangano said Nassau would use 10 miles of the county-owned aqueduct that runs under Sunrise Highway to transport treated effluent from Bay Park to the ocean-outfall pipe at the county’s Wantagh sewage-treatment plant.

The county would build connections from both plants to the aqueduct, a steel pipe built around the turn of the 20th century that once carried water from Long Island to Brooklyn.

Cedar Creek’s outfall pipe extends three miles into the Atlantic Ocean and can handle a maximum flow of 200 million gallons per day. The Bay Park flow would bring the total at Cedar Creek’s outfall pipe to about 140 million gallons per day, Mangano said.

Meanwhile, Bay Park’s existing outfall in Reynolds Channel, part of the Western Bays, would remain in place in case of emergencies, said Rob Walker, deputy chief county executive.

Mangano said the old outfall “would still be there as a backup to this. But it wouldn’t be used unless there was some issue with the new outfall.”

The county plans to issue a request for proposals in the next several weeks to hire a firm to study how the project could be engineered and to determine the condition of the aqueduct.

“It appears to be a pipe that can handle the treated effluent,” Mangano said.

The funding for the engineering study would come from state Environmental Facilities Corporation grants and loans the county holds, he said.

While the extent of the work needed still is unclear, Mangano said the proposal is broadly estimated to cost between $200 million and $300 million — millions less than building an ocean-outfall pipe at Bay Park.

“Logically it’s cheaper because you’re not constructing 2 1⁄2 miles of pipe, right? And that’s a significant savings right there,” he said. “But we have to measure that against the cost of whatever remediation, if any, is required in the existing pipe,” in addition to the cost of building the connections to the two plants.

In a statement, state Department of Environmental Conservation spokesman Sean Mahar said the agency has been working with the county to study the idea.

“This alternative, if fully feasible, would obviate the need to undertake the complex program of building a new ocean outfall at the Bay Park facility, as all effluent from both plants would be discharged from the existing Cedar Creek ocean outfall,” he wrote.

While there has been broad support for building an ocean-outfall pipe at Bay Park, officials for years have been stymied in their search for the sources of the money to pay for it.

Even when the estimated cost of construction dipped to $450 million, the county has still come up short in finding a patchwork of funding for the outfall. The state has said it would direct $150 million in federal Hazard Mitigation Grant Program money toward Bay Park, and Gov. Andrew M. Cuomo dedicated $5 million toward the outfall in the 2016-17 state budget.While the county earlier had said it would consider commiting $150 million for the outfall pipe, Mangano said the amount the county would contribute to the new proposal was yet to be determined.

“Once this alternative will be studied, we have an actual amount that we need to fund and we can then answer that question as to whether we have to seek further funding or the existing commitments would fund it,” Mangano said. “That can’t be determined until we know the exact costs involved.”

The DEC indicated on Thursday that previous funding committed to the outfall pipe could be used to support the new proposal.

Judith Enck, regional administrator for the U.S. Environmental Protection Agency, said her agency needed to confer with state and county officials about the idea.

“Anything that stops the massive nitrogen loading into the Western Bays is a good idea,” Enck said, adding that she felt nitrogen removal would need to be discussed.

“On one hand, it’s intriguing,” she said. “On the other hand, we need to know the schedule and we need to know the amount of nitrogen reduction that will take place.”

Nitrogen in the effluent from Bay Park, which serves 500,000 people, has caused severe environmental damage to Reynolds Channel in the Western Bays, a series of waterways that are part of the South Shore Estuary Reserve.

Nearly three-quarters of the total nitrogen load in the Western Bays comes from the Bay Park plant. The pollutant weakens coastal marshes, which the state has said provide critical natural buffers against wave action during storm events.

Nitrogen-removal systems already are being built at Bay Park, said Michael Martino, spokesman for Suez Water, which operates both Bay Park and Cedar Creek plants for the county.

Once those systems are in operation, scheduled to be complete by 2018, the nitrogen in the effluent would be halved, to about 17 milligrams per liter, he said.

The idea was met with enthusiasm by environmentalists and elected officials.

“This is a very exciting proposal because it appears to be cost-effective while still eliminating the discharge of effluent into the Western Bays, which have steadily deteriorated over the past decades,” state Sen. Todd Kaminsky (D-Long Beach) said in a statement. “While the feasibility of this project must be studied further, I am encouraged by this innovative development.”

Rob Weltner, president of Operation SPLASH, an environmental group in Freeport, called the idea “a very bold move.”

“If it can work and we have an existing outfall pipe that can handle it and it all looks good on paper, it’s gotta go,” he said. “It’s gotta happen.”