Berlin wastewater plant expansion advances under draft Ohio EPA permit

BERLIN, Ohio — A May 11, 2026 Ohio EPA draft NPDES permit places Holmes County’s Berlin Wastewater Treatment Plant into a more defined regulatory stage, but it does not mean the planned expansion is complete or that the plant’s treatment capacity has increased.

The Berlin WWTP, at 4829 Township Road 356, serves approximately 3,500 people in Berlin, an unincorporated community and census-designated place in Berlin Township, Holmes County. The facility discharges treated wastewater to Doughty Creek at approximately River Mile 16.57.

The existing plant has a 300,000-gallon-per-day design basis. The proposed project would increase capacity to 450,000 gallons per day, a 50% increase intended to support projected population growth and expansion of Berlin Township’s commercial and industrial base.

What the draft permit does — and does not — authorize

The May 11 document is an Ohio EPA public notice and draft permit. It was subject to a 30-day public-comment period and could have been revised before final action. The draft keeps the plant’s current operating and monitoring framework tied to the 300,000-gallon-per-day design flow while establishing conditions for the future 450,000-gallon-per-day facility.

Under the proposed permit language, Holmes County must submit an NPDES permit modification request within 30 days after construction of the approved expansion begins. Ohio EPA would then apply the future flow and effluent requirements through that modification. The draft therefore sets a regulatory path for the expansion; it does not show that the higher capacity is operating today.

Copper work is complete; broader expansion remains ahead

Ohio EPA’s fact sheet says the copper-reduction portion of the project was completed March 31, 2026. That work is separate from the broader plant expansion, which the agency said had not begun when the fact sheet was prepared.

The county planned to bid the remaining upgrades in June 2026, with an anticipated construction period of about 24 months. The draft permit records that schedule, but the documents reviewed for this article do not confirm whether the bidding occurred by Aug. 1, 2026.

Planned work includes converting an existing sludge-holding tank into an aeration tank, adding a rectangular clarifier, enlarging the ultraviolet disinfection system, adding aerobic sludge digesters and a dewatered-sludge storage building, and providing additional copper treatment.

Requirements tied to Doughty Creek

The draft permit includes copper limits and monthly monitoring for the discharge. At the current 300,000-gallon-per-day design flow, the proposed permit lists a copper daily maximum of 41 micrograms per liter and a 30-day average of 26 micrograms per liter. For the future 450,000-gallon-per-day expansion, the proposed limits are 37 and 23 micrograms per liter, respectively.

The permit also calls for monitoring of treatment performance and other pollutants, including suspended solids, ammonia, pH, dissolved oxygen, bacteria, flow and certain metals. Holmes County is proposing industrial pretreatment limits for metals and total dissolved solids from manufacturing facilities that discharge into the sanitary sewer system. The stated purpose is to prevent pollutants from passing through or interfering with the Berlin WWTP.

For Doughty Creek, the mitigation plan includes development of a nine-element nonpoint-source implementation strategy for the watershed. The strategy would document causes of impacts, identify priority areas and describe projects to reduce sediment and nutrient effects. Projects could be evaluated for funding after Holmes County completes the strategy and Ohio EPA approves it.

Ohio EPA’s fact sheet says its most recent cited evaluation, a 2009 study, found Doughty Creek downstream of the plant in attainment for aquatic-life criteria. The mitigation provisions should not be read as a finding that the creek is currently failing its designated uses.

Financing remains a future step

Ohio EPA’s draft 2026 Water Pollution Control Loan Fund plan lists the Holmes County Berlin WWTP Expansion as a construction project with an estimated loan amount of $4.304 million and an estimated award date of Dec. 10, 2026. Those are draft planning figures, not a final contract price, guaranteed award or confirmed construction start.

For Berlin residents and businesses, the practical effect is prospective: Holmes County is preparing the sewer system for additional capacity, but the increase remains dependent on final permitting, financing and construction. Businesses that discharge metals or elevated total dissolved solids may also face pretreatment requirements as the project moves forward.

Sources

• Ohio EPA 2026 Berlin WWTP draft NPDES permit and fact sheet
• The Bargain Hunter: Berlin Wastewater Treatment Plant project moving forward