south on the Delaware River DC
Looking south on the Delaware River from Penn's Landing, this is the section of the river that is experiencing the oxygen sag -- a problem with an expensive fix. PHOTO BY MEG MCGUIRE

Next step in cleaning the Lower Delaware comes with a hefty price tag

| March 24, 2021

Hey, rubber, meet the road. 

There’s no one who doesn’t want the Delaware River to be as clean as possible, but the next step comes with a hefty price tag — from $1.5 million for Trenton and as high as $3 billion for Philadelphia. 

These could be the bills for an upgrade to the 12 largest wastewater treatment facilities that flush our treated effluent into the Delaware River. 

At the Delaware River Basin Commission, many of their scientists and engineers have been studying what goes on in the river and, with other scientists and engineers all over the river, have recognized that ammonia that is — legally — flushed into the river is a problem.

It’s not a new problem.

Back in the bad old days when all manner of untreated “stuff” went into the Delaware River, the river stank. Then came the very same DRBC and the Clean Water Act, and from 1968 into the 70s, 80s and 90s, municipalities built our current wastewater treatment facilities and gave us the much cleaner river that we enjoy today. They were able to do that work because they received millions of dollars in state and federal grants as well as low-interest loans.

There are some scientific terms for what they tackled back then, which are good to understand for the next big step in cleaning up our river now.

Scientists use the term Biological Oxygen Demand to quantify the way our effluent “uses” the oxygen in the river (H2O). If there’s enough time and enough river, the river can do it all by itself. But if you don’t have that much time — or that much river — you get the stink.

As outlined by John Yagecic, DRBC’s manager for water quality assessment, back in the day they focused on the carbon piece of the puzzle, and not to be crude, but that was our poop. Its effect on the river was known as CBOD — carbon biological demand.

They knew back then that the NBOD — nitrogen biological demand — was also a problem but, as Yagecic put it, that was recognized to be a “someday problem.”

“That someday is now,” said Yagecic. Oh, and the NBOD is most easily understood as ammonia — that’s our pee. Though some of that ammonia is eliminated from out current wastewater systems, most remains.

All recognize that the work needs to be done, and the DRBC made that recognition “official” when it passed resolution 2017-4 calling for its staff to start studying the issue, and to include the various wastewater treatments plants in its investigations.

An impetus to getting this work underway is the effect this oxygen depletion has on an endangered species that has only recently returned to the Delaware — the Atlantic sturgeon and the short-nosed sturgeon.

Its young seem to have a hard time with what is called an “oxygen sag” that occurs near Philadelphia most summers, when the warmer weather means the river can’t fix our effluent fast enough.

So the DRBC paid a specialist in wastewater treatment plants to estimate what the costs would be, and its report has just been finalized and that’s where we see the numbers at the top of this story.

View the report →

The report is not easy reading but it is full of details of what sorts of upgrades could/should be made at these 12 plants.

The important part to understand, as pointed out by Yagecic, is that these figures are the beginning of a conversation that the states, DRBC, the wastewater treatment plants and the Environmental Protection Agency are having about the need to take the next step in cleaning up the Delaware.

“Nobody is taken by surprise,” Yagecic said.

The next important step is to complete the years-long modeling of the tidal bay (see the third in the series) and run that model with the various possible improvements plugged in and then see what needs to be done where to improve the river’s dissolved oxygen. Some plants may need to do all of the work priced in this report, some plants less.

In addition, when the necessary improvements are tested and agreed upon, there will need to be further conversations about the implications of the costs — and where the municipalities can turn to for help as they did in the “first generation” of improvements.

Yagecic agreed that the burden of payment can’t fall too heavily on water-systems users who would have great difficulty paying any increase in water rates.

At that point what is at this stage an environmental issue becomes a social justice issue.

Delaware Currents asked the Philadelphia Water Department for its response to the Kleinfelder Report, and it gave us a lengthy answer. We’re going to reprint it there, but the short answer is that it recognized the problem and it’s been working on finding solutions even before the DRBC took up the issue. In the Delaware Currents stories noted in the sidebar, we talked about the dynamic model that the DRBC is building to see what needs to be done where to address the DO problem. And the Philadelphia Water Department has been building its own model to find answers to this expensive problem.

Handling the city’s (any city’s) wastewater treatment system has many facets. It’s not just the waste, but also stormwater that runs through the city’s streets when it rains. Some of that gets treated, some doesn’t and the city has recently received a $107 million low-interest loan from the state’s PENNVEST program to combat that problem for one of its three plants. That improvement is not targeted toward the problem of dissolved oxygen, but to help it handle the stormwater issue.


Here’s Philadelphia Water Department’s response: 

  • We commend the Delaware River Basin Commission for the open and transparent process in which they are evaluating the Dissolved Oxygen problem and highest attainable condition for the estuary.
  • We appreciate that DRBC is not seeking to simply regulate nutrients, or assuming the Delaware estuary has the same water quality problems that occur in other estuaries, such as the Chesapeake Bay.
    DRBC is appropriately focused on the specific water quality problems in the urban Delaware estuary and is working with local stakeholders and a panel of national water quality experts to determine what levels of DO improvement are attainable. We are proud to be part of that process.
  • PWD is actively engaged in ongoing planning work. We have the same understanding of the potential costs as Kleinfelder/DRBC. Our existing Water Pollution Control Plants were built many decades ago and were not designed to remove ammonia from wastewater. Extensive and costly modifications would be needed to achieve the treatment outlined by Delaware Currents.
  • The response in the Delaware River estuary has not yet been evaluated to understand the environmental benefit of the costs, specifically the change in DO over time. DRBC and PWD understand the ballpark costs of removing the ammonia; we don’t understand yet how that translates to the DO in the Estuary. Using their respective water quality models, DRBC and PWD will conduct research to better understand how the estuary would respond to plant modifications.
  • Given the potential costs for a complete facility overhaul, and the uncertainty related to the benefit in the Delaware River estuary, PWD is actively designing a new, specialized side-stream treatment facility to reduce approximately 10% of its total ammonia load to the estuary.
  • This project would address ammonia before waste reaches our Southwest Water Pollution Control Plant, making it more cost-effective for every pound of ammonia removed compared to any full-plant upgrade options studied.
  • In addition to the facility under design, we are researching other more cost-effective opportunities at each of our three Water Pollution Control Plant facilities. There are numerous scenarios that need further exploration in coordination with Water Pollution Control Plants, the DRBC, and state agencies.
  • PWD recognizes DRBC Water Quality Manager John Yagecic’s finding that socio-economic factors must be weighed seriously in this matter. DRBC is required to take social and economic factors into account when evaluating whether higher levels of DO are attainable.
  • Most importantly, affordability needs to be considered, as PWD is a public utility funded solely by water bills and serves a large low-income population in the nation’s poorest big city.
  • We embrace integrated planning as a means of prioritizing limited ratepayer funds for the most beneficial and cost-effective projects. This allows reasonable and affordable schedules for making progress toward long-term goals. 
Meg McGuire

Meg McGuire

Meg McGuire has been a journalist for 30 years in New York and Connecticut. She started in weekly newspapers and moved to full-time work in dailies 25 years ago. She knows about the tectonic changes in journalism firsthand, having been part of what was euphemistically called a "reduction in force" six years ago. Now she's working to find new ways to "do" the news as an independent online publisher of news about the Delaware River, its watershed and its people.

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