Ohio EPA proposes first general NPDES permit for data center wastewater discharges

The Ohio Environmental Protection Agency has released a draft general National Pollutant Discharge Elimination System (NPDES) permit that would regulate wastewater and stormwater discharges from data center facilities statewide. The proposed permit, identified as OHD000001, would be the first of its kind in Ohio and is intended to streamline permitting for existing and new data centers while ensuring compliance with state and federal water quality standards.

Under the draft permit, eligible facilities could obtain coverage for discharges such as non-contact cooling water, cooling tower blowdown, boiler blowdown, air compressor condensate, and stormwater associated with industrial activity, rather than seeking individual NPDES permits. The permit includes effluent limits and monitoring requirements for parameters including temperature, oil and grease, total suspended solids, chlorine, phosphorus (when applicable), pH, and total filterable residue, with an emphasis on minimizing impacts to receiving waters.

Ohio EPA is proposing a five-year permit term and will subject the draft to public notice and a mandatory public hearing under the state’s antidegradation rules. Facilities seeking coverage would be required to submit a Notice of Intent and pay a $200 application fee. The agency is accepting public comments before finalizing the permit, which would establish a consistent regulatory framework for managing wastewater discharges from the rapidly expanding data center sector.