Delaware Public Media

Rehoboth Beach pulls wastewater discharge from canal

Jun 1, 2018

The City of Rehoboth Beach met a state and federally mandated June 1 deadline on Friday to pull its wastewater discharge from the Lewes-Rehoboth Canal.


After decades of discharging treated wastewater into the canal which flows into Rehoboth Bay, Rehoboth Beach is now sending city and county-treated wastewater a mile out into the Atlantic Ocean through a three-mile-long pipeline that starts at the city’s wastewater treatment plant.

“We are very proud about what we’ve done to start the enhancement of the Inland Bays,” Rehoboth Beach Mayor Paul Kuhns said. “This is going to be great for the environment throughout the Inland Bays.”

Based on discharge amounts from city and state permits, getting Rehoboth’s point source discharge out of the canal will remove over 17,000 pounds of nitrogen that enters the water annually, Delaware Center for the Inland Bays Executive Director Chris Bason told Delaware Public Media in a May interview.

Although it’s a move that will benefit the Inland Bays, some environmentalists worry it will harm the ocean.

Gregg Rosner, the conservation chair from the Delaware chapter of the Surfrider Foundation, stood Friday by Henlopen Hotel outside of the beach and pointed out the dolphins swimming by.

“You’ve got beachgoers looking at the dolphins, they’re amazed and just entranced by them,” Rosner said. “And we’re not being responsible in the slightest bit.”

Rosner said he is particularly concerned about pharmaceuticals and endocrine inhibitors that could remain in the wastewater after treatment.

“Fish like to congregate around areas of turbulence and whatever else is coming out,” Rosner said. “It’s all part of the chain of the ocean and an outfall interrupts the natural state of the ocean.”

An Environmental Impact Statement for the project done by GHD Engineering said pharmaceutical concentrations “are expected to be minimal” since Rehoboth is treating to a tertiary level.

That tertiary level, which Rehoboth Beach had to upgrade to, is a high level of treatment that can remove 99.5 percent of pollutants like nitrogen and phospherous, said Gerald Kauffman, the director of the University of Delaware Water Resource Center. Most treatment plants do secondary treatment, which uses biological processes to break down pollutants.

“So by the time Rehoboth’s wastewater is discharged into the Atlantic Ocean, it’s going to be at the highest level of treatment anywhere in Delaware or the Mid-Atlantic,” Kauffman said.

The high flushing rate of the Atlantic Ocean will dilute toxins from the water, Kauffman said. In contrast, the Lewes-Rehoboth Canal has low flushing and dilution rates.

Additionally, in some other areas where pharmaceuticals are being detected, there are typically pharmaceutical plants in the watershed - like the Brandywine River Watershed. There are no industrial pharmaceutical operations in the Rehoboth area, however.

"I'd be more concerned if there was an industrial [pharmaceutical] plant in the area," Kauffman said.

The barge that worked on the Rehoboth outfall.
Credit Courtesy of City of Rehoboth Beach

In 1998, Delaware’s Department of Natural Resources and Environmental Control started looking at what nutrients were going into the Inland Bays and where they were coming from. Rehoboth Beach then signed an agreement in 2002 to pull the discharge from the canal.

After reviewing wastewater disposal options like land application and an ocean outfall pipe, a 2015 referendum authorized spending $52.5 million for an ocean outfall project.

And unlike land application, the ocean outfall is something residents and tousits cannot see.

While enjoying the beach Friday, frequent beachgoers Lee and Sherry Bye, who live just outside of Rehoboth, said they’re not bothered by treated wastewater going into the ocean.

“It’s not a big issue that would ever keep us away from the beach anyhow,” Lee Bye said.

As for work that still needs to be done, the contractors are paving the roads where they’ve buried force main pipes.

The city is also upgrading aging infrastructure at its wastewater treatment facility.

This story has been updated.