Local environmental groups split on Rehoboth Beach outfall project
By Eli Chen - January 30, 2015
On a regular day, the Rehoboth Beach Wastewater Treatment Plant takes in about 1.3 million gallons of sewage from Rehoboth Beach, Dewey Beach, Cape Henlopen Acres and North Shores.
“The pipe on the far left — that’s the influent. That’s the waste coming in from the community,” said Bob Stenger, manager of the plant since 1986.
From a metal bridge overlooking where the sewage is flowing, Stenger explains how nitrogen, phosphorus and dissolved oxygen are reduced in the treatment process.
“The organisms in that tank have the ability to extract the oxygen molecules from the nitrate and you’re left with nitrogen gas and that vents into the atmosphere,” said Stenger.
After it completes the treatment process, the influent eventually becomes effluent. It then travels through the Lewes-Rehoboth canal and out into Rehoboth Bay, the head of the Inland Bays. This is the way the plant has operated since it began in 1935.
But that might change soon. On January 5th, DNREC secretary David Small signed a record of decision that would allow the city of Rehoboth Beach to borrow $25 million to build a pipe that will redirect the effluent to the Atlantic Ocean.
The Rehoboth Beach wastewater treatment plant has long contributed to pollution in the Inland Bays, which has been listed by the EPA as impaired waters. Chris Bason, executive director of the Center for the Inland Bays, says that excessive nutrients from sources like wastewater treatment plant has squandered life in the Bays.
“It really completely changes the ecosystem, from one that’s dominated by fish and by bay grasses to one that’s dominated by floating algae,” said Bason. :It turns waters that are naturally clear into murky waters.”
While the plant has installed upgrades to lower the concentrations of nutrients in their effluent, the best way to lower its impact on the Bays is to stop it from entering Rehoboth Bay.
“Our discharge limit is zero. That means we can have no nitrogen or phosphorus going into the inland bays,” said Stenger. “There’s no technology that will allow us to stay in the same configuration of the process and discharge to the Inland Bays at zero.”
For the last 10 years, DNREC and the city of Rehoboth Beach have analyzed various alternatives for redirecting the effluent out of the Inland Bays watershed. Of the alternatives, two have floated to the surface: one is the ocean outfall. The other is land application, meaning that the sewage would be used as fertilizer for agricultural land.
“It was a difficult decision,” said Small.
Even Small’s predecessor Collin O’Mara, now the president and CEO of the National Wildlife Federation, couldn’t commit an official position on the issue during his term as DNREC secretary.
The Delaware Chapters of the Sierra Club and the Surfrider Foundation have spoken vehemently against sending the wastewater to the ocean and pushed for the land application option. However, most of Rehoboth Beach’s city officials, including mayor Sam Cooper, and the Center for the Inland Bays support the ocean outfall plan.
“I understand the importance and value of tourism and the perception issue that folks have about this. And what we tried to do was think about our charge to clean up the Inland Bays,” said Small. “This is a process that’s been underway for decades. The thought of being able to eliminate the last single largest wastewater discharge into the Inland Bays and have all that wastewater go out of that watershed was really what swung it for me.”
The final environmental impact study, completed in early 2013, deemed the ocean outfall as the most cost-effective and environmentally friendly route. It stated that the impacts on marine life would be minimal.
“Basically there are outfalls all over the country. We know what they do and very few of them have biological impacts,” said Bill Ullman, a University of Delaware marine scientist who specializes in small estuaries. “Is there potential for affecting organisms? Yes, there is because we’re putting them in an area, the hen and chicken shoals where there is a population of small sharks.”
Ullman says given the length and location of the proposed ocean outfall pipe, the treated wastewater will have little impact on the surrounding wildlife.
“We’re talking about maybe a 30 to 36 inch pipe. It’s being diluted by water coming in down from the Delaware Bay, which is 12 miles of pipe. An enormous pipe. And this water is going into a 36 inch pipe, makes no difference when you scale it against the volume that’s coming down from the Bay to start with,” said Ullman. “I find it really hard imagine other than immediately around where you put the discharge pipe that there’s going to be any impact.”
The coastal ocean near Rehoboth Beach flows differently than Rehoboth Bay. Waters move quickly along the coast, due to the tides coming in from the Delaware Bay. This causes the nutrients to disperse faster than they would out in the shallow and not so well-flushed areas of the Inland Bays,
Chris Bason pointed to a chart on his office wall that demonstrated how long nutrients persist in Rehoboth Bay.
“In that area of the bay, it’s over 40 days on average, or some studies show that 90 days that a particle, once it enters the [Rehoboth Bay], is going to stay in that bay,” said Bason.
Ullman added that there is also another ocean outfall in South Bethany, which so far hasn’t demonstrated any significantly adverse impacts on marine life nearby.
“We all remember the saying that dilution is not the solution to pollution,” said Ullman. “The fact is, it’s a partial solution. It’s not the whole solution. But it does work.”
This is where local environmental groups disagree. Suzanne Thurman, executive director of the Marine Environmental Research and Rehabilitation Institute, is especially concerned about potentially hazardous substances that cannot be removed from the effluent.
“There are certain substances that cannot be extracted during the traditional wastewater treatment. Pharmaceuticals, endocrine inhibitors, caffeine, heavy metals. Those are still going to be present in huge concentrations in the plume,” said Thurman.
The Delaware Chapters of the Sierra Club and the Surfrider Foundation have expressed similar concerns about exposing some of the more fragile marine life to the contents of the effluent.
In 2012, the National Oceanic Atmospheric Administration (NOAA) released their comments on the ocean outfall. Their statement said the outfall would adversely affect the essential fish habitat. It also noted potential negative impacts the pipe would have on endangered species, which include several species of sea turtles and sturgeon. Additionally, benthic organisms, like clams and oysters, that serve as food sources for marine life could also be affected.
John Doerfler, vice chair of the Delaware Surfrider Foundation, believes constructing an ocean outfall will only transfer the pollution in the Inland Bays to the ocean, where there are other sources of pollution for marine life to contend with.
“If it has proven so hazardous to the Inland Bays, you’re still putting the same hazards into another body of water. You can say that it dilutes all you want, but it’s still in that water,” said Doerfler. “You’re talking about pollution from New Jersey, the Carolinas, Virginia. Everything is in that gulf stream there. If there’s a better solution that takes it out of the Bays and keeps it out of the ocean, then why wouldn’t you go with that solution?”
Doerfler is talking about spray irrigation, a type of land application. Secretary Small noted that in most cases, DNREC would usually prefer to use treated wastewater for land application.
The case of Rehoboth Beach, however, is an exception for two reasons. One, its proximity to the ocean. And two, concern that the nutrients would still run off into the Bays. Bason explains how land application would still impact the Inland Bays.
“The Inland Bays are, interestingly, primarily fed through groundwater. Our watershed here is like a big sandbox, it has very sandy soils. So water that lands on the surface will infiltrate the aquifer, which is eventually going to discharge into the Bays,” said Bason.
The lack of viable lands and willing landowners near Rehoboth Beach also steered Small to decide against land application.
Whether or not the outfall pipe is the most environmentally responsible choice, Ullman says that no option here is perfect.
“The perfect solution would be to have no people. If we have no people, we have no problem,” said Ullman. “The problem is that people move into tightly closed spaces and produce a lot of waste. If we get rid of people, we solve the problem. But that’s not the problem we’re trying to solve. We’re trying to keep the people and still minimize their impact.”
Even though Small has approved loan funds, no permit has been issued yet to build the ocean outfall. As part of the approval, DNREC has also required the city of Rehoboth Beach to evaluate its stormwater system — which will have a more direct impact on the condition of its beaches than the outfall.
The next step in the ocean outfall’s approval process lies with the city of Rehoboth Beach. Officials will hold a bond vote sometime this year to come up with the funds it will need to allocate to the project.
- See more at: http://www.wdde.org/72553-rehoboth-outfall#sthash.zB2xct7t.dpuf