BioCEPT at the Akron Water Reclamation Facility. Photo: Eric SandyYou don’t commission something like BioCEPT unless you’re under serious pressure. And in Akron, that pressure came in the form of a $1.2-billion EPA consent decree, one aimed squarely at preventing untreated combined sewer overflows, in the modeled typical year, into the Cuyahoga River.
It’s a consent decree benchmark that’s arguably the most stringent in the country.
But while the timeline was regulatory (and wrapping up in the near-term future), the solution turned out to be something else entirely: an operational experiment that’s pushing boundaries in real time.
A safety net
BioCEPT—short for Biological Chemically Enhanced Primary Treatment—helps Akron manage massive inflows during storm events. It’s built to treat an additional 60 million gallons per day of wastewater, boosting the Water Reclamation Facility’s total capacity to 280 MGD with full biological treatment.
What makes BioCEPT unique is that it stabilizes peak flows using aerobic microorganisms—essentially applying biological treatment to wastewater that would otherwise bypass a portion of the plant. Once that initial stabilization occurs, chemical additives—typically polymers—are introduced to help remove remaining solids and impurities.
The treated flows from BioCEPT are then blended with conventionally treated water before disinfection and release into the Cuyahoga River.
The result? A flexible, high-rate treatment system that protects the river during storms—without overloading secondary treatment.
But it isn’t built to run 24/7. It’s insurance.
Operators only activate it when headworks flow pushes past ~260 million gallons per day. In a city that has seen 4-inches of rain in 2-hours (see August 8, 2024, for starters), that’s a prudent investment.
“We’ll fill it. We may not actually put effluent out of it, but that gives us about eight hours of fill,” Akron Water Reclamation Facility superintendent Steve Baytos says.
That retention buys precious time. When the system hits 270 MGD and the rest of the plant’s running hot, BioCEPT kicks in to avoid secondary bypasses. Thanks to upstream tunnel construction with available storage, it doesn’t run often—but when it does, it matters.
Timing is everything
BioCEPT at the Akron Water Reclamation Facility. Photo: Eric SandyOperators are quick to point out: just because you can run it, doesn’t mean you should.
“Chemicals are expensive. And if we don’t have to use it, we won’t,” Baytos says, mindful of the facility’s budget.
Early runs used standard polymer blends. Eventually they switched to dry-feed polymer packs with a longer shelf life. That cut waste. It also helped avoid the classic trap of having tanks full of chemical slush that’s gone bad.
But the bugs? That’s trickier. BioCEPT relies on aerobic biological activity to hit its targets. Problem is, those bugs don’t live forever.
“If we ran it at 60 MGD for almost two days, we would run out,” Baytos says. “We’d have to shut it down.”
Add in heating requirements during winter and the need to drain tanks seasonally, and the operational calculus gets more complicated fast. Still, Akron’s operators are finding workarounds, like leaving tanks full to maintain temperature, even 15 feet underground.
What changed? Real-time monitoring
The shift from reactive to real-time decision-making was huge. It’s a reminder to all operators of the importance of having eyes on the whole facility all the time.
With mag meters and real-time sensors now in place, operators don’t have to guess. They can trigger chemical additions and flow adjustments in the moment—not based on lab slips from yesterday. It’s a seemingly small upgrade with massive implications when you’re operating on the edge of overflow.
What makes BioCEPT unique isn’t just its chemical-biological process. It’s how it fits into the broader sewer collection system under the watchful eye of Baytos’s team. Akron’s real-time control system treats wastewater like a bank account, one where “negative cash” signals the risk of overflow.
This is the first EPA consent-decree high-rate biological treatment system in the country. In Cleveland, overflows can reach 500 million gallons in a single rain event. Akron’s team? They’re trying to make zero overflows in the modeled typical year the norm.
And soon, they’ll have a second tunnel in service, slated for the end of 2026. BioCEPT remains the short-term scalpel in a broader surgical suite.
Built for flexibility, fueled by reuse
Beyond storms, BioCEPT’s value shows up in other moments too. Think belt-press shutdowns, aeration tank outages, and mid-plant bypasses. Its ability to absorb and treat internal flows has become a kind of operational Swiss army knife.
And then there’s the sludge.
“We take our sludge—we don’t send it to a landfill. We started composting,” Baytos says. “Now we produce EQ sludge at our Renewable Energy Facility (REF).”
Akron’s pretreatment program has cut industrial metals to the point where biosolids are now land-applied. Crops. Compost. Circular systems. When your high-rate treatment also supports regenerative ag, you know you’re onto something.
Human lessons
Engineers designed BioCEPT. Operators made it work.
Early versions had too many valves, pipes, water cannons. It was over-engineered. The team pared it down, got smarter with chemistry, and leaned on experience. A core lesson that many in the business can grasp: Engineers are smart. Sometimes operators are smarter.
In other words: design gives you a framework. But only lived-in knowledge makes a system sing. The goal is automation, sure. But until then? Judgment, intuition, and midnight decisions still matter. A lot.
“Now it’s real time,” Baytos says. “You just click a button, turn it on.”
What’s next?
BioCEPT at the Akron Water Reclamation Facility. Photo: Eric SandyBioCEPT is just one piece of Akron’s compliance stack. Pretreatment, headworks upgrades, tunnel capacity, biosolids, all of it feeds into a single mandate: zero overflows in the modeled typical year.
It’s working. The Cuyahoga River has officially been de-impaired. Dam removals have returned steelhead. And Akron’s team is already in active conversations with regulators about long-term targets and how to define “good enough.”
Because even with the gains, the work isn’t done.
Akron is building a model
Under the aegis of the consent decree, Akron’s investment in BioCEPT can be seen as a pragmatic, hard-won innovation under pressure. What Akron’s team is proving—quietly, iteratively, in real time—is that consent decree compliance doesn’t have to be reactive. It can be strategic.
With BioCEPT, they’re setting a new standard for what mid-sized cities can accomplish: blending biology and chemistry, resilience and reuse, engineering and operator intuition.
And in the years ahead, more cities will be watching—not just to see how BioCEPT holds up during the first major wet season with the tunnels online, but to ask the bigger question:
What happens when your last line of defense becomes your best tool for the future?
