Concrete Solutions
How modern engineering is helping restore clean water in Long Island’s Western Bays
By Kate Frazer
Long Island’s South Shore, home to some of America’s first suburbs, was built after World War II on the promise of idyllic coastal living: easy access to beaches, fishing and life on the water. Yet over the years, the water told a different story. Seagrass thinned, marshes weakened, shellfish declined and algae blooms spread where kids once swam and clammed. For decades, the Western Bays absorbed nitrogen pollution from a sewage treatment plant that sent more than 50 million gallons per day of treated wastewater into Reynolds Channel. The excess nitrogen fueled algae blooms, degraded salt marshes and weakened coastal resilience.
Now, thanks to years of advocacy, rigorous science, visionary engineering and municipal cooperation, that trajectory is changing. The Bay Park Conveyance Project, a roughly $440 million partnership between New York State and Nassau County and federal agencies, is mechanically complete and nearing full operation. Prior upgrades already cut nitrogen from the plant roughly in half, and now the treated wastewater will be routed away from the nitrogen‑sensitive Western Bays and to an existing ocean outfall pipe three miles offshore, where studies show there will be no ecological harm.
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Bottom line for bays and people: diverting treated wastewater out of these warm, shallow waters will lower nitrogen dramatically, giving marshes, wildlife and coastal communities room to recover and thrive.
Road to Recovery: Nitrogen Pollution, Causes and Fix
Nature Conservancy supporters and partners were instrumental in making this project possible, advocating for funding, mobilizing volunteers and rallying local leadership to move this effort from concept to construction. Alongside Citizens Campaign for the Environment and Operation SPLASH, TNC helped secure critical funding, conduct scientific research and build public support.
New York Ocean Programs Director Carl LoBue, who served on the South Shore Estuary Reserve Council, helped guide the research that laid the groundwork for the conveyance project.
“We were watching the ecosystem unravel in real time,” LoBue said. “Marshes were collapsing, shellfish beds were contaminated, waterways and beaches were choked with rotting algae. People could no longer enjoy the beaches and bays in the way they once could. We knew we had to act.”
For Scott Bochner of Operation SPLASH, the pollution was visible and impossible to ignore. From his home in Long Beach, he could look out over Reynolds Channel and see the discharge, known locally as “the Block.”
“I could see it, and I could smell it, every time there was a problem at the plant,” Bochner said. “There shouldn't be anything in treated wastewater birds can eat, and yet there often was.”
The dedicated crews at Operation SPLASH have removed more than three million pounds of trash from wetlands and beaches. But when trash clean-ups alone didn’t restore the bay, they followed the odor back to its source, uncovering a deeper systemic failure. Their on-the-water observations, photos and logs helped spark what became the Western Bays Coalition, which also includes Citizens Campaign for the Environment and The Nature Conservancy.
Quote: Adrienne Esposito
Turning off the tap on excessive nitrogen from sewage effluent will turn a dying bay into a thriving bay.
LoBue describes the methodical early years of the effort: “People had a strong sense of what the problem was, but before hundreds of millions of dollars of public investment could move forward, it had to be proven beyond any doubt.”
The coalition secured nearly $2 million in research funding, allowing scientists at Stony Brook University to analyze water circulation patterns and ecological impacts, showing that Reynolds Channel was far less diluted by ocean water than originally believed. And instead of flushing out to sea, treated wastewater was pushed back into the bays, sloshing back and forth and concentrating nitrogen pollution.
Superstorm Sandy, Wastewater Failure and a Path Forward
Then, in October 2012, days after coalition members reviewed the study findings with agency leaders in a packed conference room, Superstorm Sandy flooded the Bay Park facility with a 9-foot tidal surge, releasing 2.2 billion gallons of partially treated sewage and about 2 million gallons of raw sewage into the Western Bays and surrounding neighborhoods.
The disaster exposed the system’s fragility and opened the door to recovery funds. A long‑discussed solution suddenly moved from theoretical to achievable.
By then the science was unequivocal: nitrogen pollution wasn’t just fueling algae blooms; it was weakening the salt‑marsh islands that buffer communities from storm surge. Fixing the problem meant two things: upgrading treatment to cut nitrogen and moving the wastewater out of the bays.
The price tag was steep, and for years progress seemed uncertain. Then came a breakthrough: Nassau County's engineers proposed repurposing a century‑old aqueduct beneath Sunrise Highway to carry treated wastewater east to an existing ocean outfall, where it is diffused and dispersed. The creative solution slashed costs and revived momentum.
It was a watershed moment—evidence that steady civic engagement, credible science and practical design can convert a chronic water‑quality problem into a buildable solution.
How It Works: Engineering for Ecosystems
Crews used low-impact microtunnel boring machines to construct nearly 11 miles of underground pipeline 20-60 feet below ground, threading new life through a 100-year-old aqueduct with minimal disruption to the communities above.
It’s gray infrastructure delivering green impact. By sharply reducing nitrogen pollution, the project is:
- Restoring water quality
- Supporting fish and birds
- Reviving shellfishing potential
- Helping rebuild marshes that protect coastal communities
- Strengthening wastewater services for hundreds of thousands of residents as extreme weather intensifies, improving public safety
Bay Park also offers a model for other coastal regions confronting aging wastewater systems, declining water quality and climate vulnerability. From coastal New England to the Gulf Coast and across the globe, communities can look to the project for a road map that blends science, engineering and community advocacy into real, measurable clean-water gains.
How This Work Advances TNC’s Global Clean‑Water Goals
Every local win adds up. By reducing nitrogen at the source and restoring bay health, this project supports TNC’s global goals for clean water—protecting drinking‑water security, improving estuary function and strengthening coastal resilience. Supporters help scale these solutions through policy change, funding and replicable approaches that other communities can use.
What’s Ahead: Safer, Smarter Water Systems
Even as the conveyance system comes online, critical vulnerabilities remain:
- Approximately 35,000 residents in the City of Long Beach still rely on an aging, storm‑exposed treatment plant. Converting that facility into a pump station—with treatment shifted to Bay Park—is expected within two years.
- Beachside community Point Lookout still depends on outdated cesspools, with no approved referendum yet to connect homes to modern sewer infrastructure.
- Much of Nassau County’s wastewater collection system has exceeded its life expectancy. Leaky pipes allow groundwater to infiltrate the network during storms, reducing treatment capacity and putting recent investments at risk.
- Recent sinkholes—some beneath school bus routes—underscore the urgency of upgrades.
The Nature Conservancy continues to advocate for comprehensive wastewater modernization through the Environmental Protection Fund, New York’s Bond Act and federal infrastructure programs. And we’re pairing this work with on-the-ground projects that restore salt marshes, rebuild shellfish reefs and help communities adapt to climate impacts across the state. For supporters, that means every gift helps secure clean water today and protects the systems communities rely on tomorrow.
Cleaner Bays, Healthier Communities—A Lasting Return on Persistence
“Turning off the tap on excessive nitrogen from sewage will turn a dying bay into a thriving bay,” said Adrienne Esposito, executive director, Citizens Campaign for the Environment. As the final connections are made and the system comes fully online, the Bay Park Conveyance Project helps restore something essential for coastal communities: the ability to live alongside the water without harming it. Families, fishers, boaters and others will be able to enjoy these waters with confidence, knowing their communities are on a cleaner, more resilient path.
This is not just proof of what’s possible, it’s a new model for how communities and coastlines can thrive together by using collaboration, science and innovative thinking to solve even the toughest environmental challenges.
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