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Rehoboth Ocean Outfall: Past, Present and Future

Courtesy of City of Rehoboth Beach
The barge and support vessels working on Rehoboth Beach's ocean outfall.

The Rehoboth Beach ocean outfall went live at the end of May. It’s now discharging treated wastewater into the Atlantic Ocean.

The city has been working on this project for a number of years after being mandated to stop discharging into the Lewes Rehoboth Canal. But the environmental opposition to this project remains, raising the question “what sort of oversight does the outfall need going forward?”

In 1998, Delaware’s Department of Natural Resources and Environmental Control said there were too many nutrients like nitrates and phosphates going into Delaware’s Inland Bays through municipalities and corporate wastewater treatment.

Around that time, the City of Rehoboth Beach was treating its wastewater and emptying it into the Lewes-Rehoboth Canal, which goes into Rehoboth Bay. Rehoboth was one of more than 10 different cities and corporations DNREC approached, saying they would like them to limit their discharge going forward.

They signed an agreement in 2002 to stop discharging into the canal in the future.

Mayor Paul Kuhns said the city considered alternatives for how to dispose of its treated wastewater, including sending it to the ocean through an ocean outfall, or spraying it on agricultural land. The latter form of disposal allows water to travel through the groundwater and it can get back into the Inland Bays.

“We wouldn’t have really been eliminating, we may have been limiting the nitrates and phosphates,” Kuhns said. “But some of the problems they have in agricultural situations – where there still are nitrates and phosphates going into the Inland Bays – we’re very happy not to be a part of that any more.”

The city went into referendum in 2015 to budget $52.5 million for the outfall, a new effluent pumping station at the treatment plant, treatment plant upgrades and changing the disposal of biosolids generated from the treatment plant to a different land application class method.

The outfall would send treated wastewater from Rehoboth, Dewey Beach, Henlopen Acres and North Shores, out to the ocean. All of these communities utilize Rehoboth’s wastewater treatment plant.

The outfall won by about 30 votes.

DNREC Secretary Shawn Garvin approved the outfall in May 2017, allowing Rehoboth Beach to pipe treated wastewater from its treatment plant out to the ocean, about a mile away from the Deauville Beach parking area, to an area of the water about 40 feet deep.

Because of the number of Sussex County communities that use Rehoboth’s wastewater treatment plant, Sussex County became a 42 percent partner on the project in summer 2017.

Environmental opposition to sending treated wastewater out into the ocean:

Before the referendum, Rehoboth contracted engineering company GHD to facilitate an environmental impact statement for the project.

GHD analyzed how ocean outfall construction could affect marine life in the area. Citing a study about how sound can affect marine mammals, it determined “minor impacts may occur to marine mammals during construction of the ocean outfall.”

Suzanne Thurman, the executive director of the Marine Education Research and Rehabilitation Institute filed an appeal with the state’s Environmental Appeals Board to ensure work stoppages be put into place. The board met in January and determined she did not have standing and could not prove personal harm from the outfall.

Thurman also said she would've liked to see third-party trained observers hired to look out for marine mammals.

"We wouldn't have really been eliminating, we may have been limiting the nitrates and phosphates." -Mayor Paul Kuhns talks about land application disposal.

Manson Construction, the contractor doing the ocean work on the project, was expected to look out for marine mammals while working, and report them to MERR and stop working if necessary.

Some projects that utilize ocean work require an Incidental Harassment Authorization permit through the National Oceanic and Atmospheric Administration. This is permitted under the Marine Mammal Protection Act and allows contractors to harm a few marine mammals while doing their work.

Rehoboth did not need one of these permits, according to an email from NOAA Fisheries Greater Atlantic Region Habitat Office. NOAA told Delaware Public Media they completed a consultation in June 2016, determining the outfall would not have an adverse impact on endangered species, and did a consultation on Essential Fish Habitat with the Army Corps of Engineers in August 2016.

“We issued a Conservation Recommendation for soft starts on the pile driving,” NOAA said in an email to Delaware Public Media. “The project included no in-water work from May 1 to Oct 1, so additional seasonal restrictions were not needed to address Essential Fish Habitat Concerns.”

But bad weather in March and April threw the ocean work of the project off schedule.

Originally, Manson Construction was mandated to be out of the water by April 1. The Army Corps of Engineers and DNREC extended their permits through May – a key species migration time – determining “the additional time would not have an adverse impact on any endangered species,” according to the Army Corps of Engineers.

Mayor Paul Kuhns said he was grateful for that extension, as the city knew it was running against the clock.

“If you look at the permitting process, we were given limitations on time because of the environment,” Kuhns said. “As the water gets warmer, more marine mammals come up through that area. Fortunately, bad weather in some ways was good for us because the water stayed cold. It allowed DNREC as well as the U.S. Army Corps of Engineers to do their analysis and say ‘it’s still cold water, we can let you work a little bit further.”

But Thurman said she believes due diligence was not done on that part.

“[Marine mammals] have other environmental indicators that tell them it’s time to start their movement,” she said. “That has a lot to do with the length of days, the rays of sunlight, not as much the temperature. Temperature can dictate some things, but our first dolphin sightings are in February now.”

And so far, she said, the MERR Institute has seen a higher number of dolphin strandings this year than in the past. They’ve responded to over 20 – most happening between April and May this year.

It’s unclear whether or not those strandings are associated with the construction of the ocean outfall, as a dolphin could become ill and travel for a little while before washing up on the shore, she said.

“We would have to assemble a series of tissue samples and see if we can identify the specific toxins that might be on our radar,” Thurman said.

Additionally, unusual mortality events were declared for humpback whales, North Atlantic right whales and minke whales in 2017, after the environmental assessment was completed. This means a high number of these whales have been dying along the coast. 

Gregg Rosner, Delaware Surfrider Foundation: "We're not being responsible in the slightest bit."

Gregg Rosner, the conservation chair of the Delaware chapter of the Surfrider Foundation, echoed Thurman’s concerns about treated wastewater’s effect on marine life. On June 1, the day Rehoboth Beach was mandated to be out of the Lewes-Rehoboth Canal, Rosner stood at Henlopen Hotel in Rehoboth, looked out to 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. And we’re not being responsible in the slightest bit,” Rosner said.

Rehoboth Beach had to upgrade its treatment plant to a tertiary treatment, which, according to the University of Delaware Water Resources Center, will remove 99.5 percent of phosphorous and nitrogen in the water. But there’s a fear that pharmaceuticals that tend to remain in wastewater after treatment will affect ocean health, Rosner said.

“The science of it is the chemicals of wastewater disposal is hydrophobic and lipophilic,” Rosner said. “They love the fat of dolphins, love the fat of fish. Hydrophobic – they don’t attach themselves to water molecules. They exist in microlayer of the ocean, they all go up to the top.”

“On a west wind in Rehoboth Beach – you’re basically swimming in pharmaceuticals,” Rosner said.

Gerald Kauffman, the director of UD’s Water Resources Center, says since Sussex County does not have any big pharma, there’s a low probability of pharmaceuticals getting into the wastestream.

“If it is getting in there, it’s because people are flushing it down their sinks and toilets,” Kauffman said.

While the ocean, he said, is expected to significantly dilute nitrates and phosphates with its quicker flushing times, it’s uncertain what will happen to pharmaceuticals.

“The monitoring will tell us,” Kauffman said.

Monitoring the ocean outfall:

Based on Rehoboth Beach’s permit, the city has to conduct frequent testing on its wastewater before sending it to the ocean, Mayor Kuhns said.

Once every five years, divers will go out to monitor the pipe.

The city is installing substantial generators at the plant to make sure if there is an outage or a mishap at the treatment plant, that they could quickly move from one system to another, Kuhns said.

Mayor Paul Kuhns: "We’re doing as much as we can to make it just water going out there."

As Kuhns said, there’s always concern related to what’s going through the city’s wastewater pipes. But the city has been upgrading its wastewater treatment plant even since before the mandate to get out of the Lewes-Rehoboth Canal.

“We’re doing as much as we can to make it just water going out there,” Kuhns said.

Rosner and other members of the Delaware chapter of the Surfrider Foundation have pointed to recent studies on mussels in Puget Sound in Washington, where mussels tested positive for opioids.

Puget Sound, however, has a lower flushing rate than the Atlantic, Kauffman said.

Sussex County has another ocean outfall:

Sussex County has one other ocean outfall that has been discharging treated wastewater from the South Coastal Regional Wastewater Facility near Bethany into the ocean since 1979.

Loran George, a district manager at the facility, says the outfall and the treatment plant have been in compliance at least since he’s been with the county since 1989.

He said they’ve had “minimal issues, minor issues,” along the way, but "nothing we couldn’t take care of.”

“Maybe a pump goes down, but most areas of the plant have two to three pumps in them,” he said.

On average, the South Coastal facility treats more than 2 million gallons of wastewater a day, before sending it to the Atlantic. It has a capacity of 7 million gallons. Rehoboth Beach can handle a capacity of about 7 million gallons of wastewater a day as well, but on average, treats about 1.5 million gallons a day.

Kuhns says he expects Rehoboth Beach to treat as much as 3-3.5 million gallons of wastewater a day during the busiest weekend – Fourth of July weekend, before sending it to the ocean.

Work that still needs to be done:

Though Rehoboth Beach is already sending treated wastewater from its wastewater treatment plant to the Atlantic Ocean about a mile offshore from the Deauville Beach parking area, it is still working with a contractor to pave the roads where they buried force main pipes to send the water to the ocean.

Kuhns said on Friday, June 1, that he expects that to take between 10 days to two-and-a-half weeks.

After that, the city will continue to make upgrades to its treatment plant, including the biosolids portion of the project.

Sussex County, a 42 percent partner on the project with the ability to become a 50 percent partner in a year, will help pay for the biosolids portion, according to both the city and county.

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