The city’s current Wastewater Treatment Plant is designed to process a flow of seven million gallons per day (MGD). The current average daily flow is 4.25 MGD, or approximately 61% of the plant’s current design capacity.
The Environmental Protection Agency monitors the city’s National Pollutant Discharge Elimination System (NPDES) permit. The permit contains limits on what can be discharged, as well as monitoring and reporting requirements, and other provisions to ensure that the discharge does not hurt water quality or people's health. The city’s permit requires a minimum removal efficiency of 85%. The city’s soluble pollutant removal efficiency was 97.8% in 2021 and was 96.3% for suspended solids.
The city’s industrial base is the fourth largest in southwest Ohio; the city has 16 significant industrial users (SIU). These identified SIUs are subject to additional pretreatment standards as well as additional sampling and inspections by local staff. In 2021, 58 Notices of Violations were issued to the local SIU companies. While this was an increase over previous years, staff continues to work with all industrial users to achieve and maintain program compliance.
In 2021, the plant saw a reduction in the electric operating expenses compared to the previous four years. A marked increase in chemical costs was observed during the year.