Warren County was identified as a Small Municipal Separate Storm Sewer System (MS4) community by the U.S. EPA in 1999 and was granted a discharge permit in 2004. 2009 marked the beginning of a new five-year term under the revised permit. The Warren County Engineer's Office administers the County's MS4 permit under the National Pollutant Discharge Elimination System (NPDES) commonly known as Phase II.

Warren County Phase II Stormwater General (MS4) Permit

**View MS4 Permit on Ohio's Environmental Protection Agency's Website at epa.ohio.gov

Warren County Storm Water Management Plan

Included in the permit are six minimum control measures including:

• 1. Public Education and Outreach
• 2. Public Involvement/Participation
• 3. Illicit Discharge Detection and Elimination
• 4. Construction Site Runoff Control
• 5. Post Construction Stormwater Management
• 6. Pollution Prevention and Good Housekeeping for Municipal Facilities.

The WCEO coordinates this permit for the Townships of Clearcreek, Franklin, Hamilton, Turtlecreek, and Union and the Villages of Maineville and South Lebanon. The WCEO's administration includes annual reporting, planning, and meeting the requirements of the permit by collaborating with other local agencies such as the Warren County Combined Health District and the Warren County Soil and Water Conservation District.

The most recent Small MS4 Annual Report:

2013 Small MS4 Annual Report