Municipalities with combined sewer systems must include all wet weather discharge points in the discharge permit applications for their respective publicly owned treatment works (POTWs). The application requirements for a municipal wastewater discharge permit (KPDES Form A) with CSOs are listed in 401 KAR 5:060, Section 5 (8).

Combined Sewer Overflows

Facts about combined sewers and combined sewer overflows:

• What are combined sewers and what is a combined sewer overflow?

Combined sewers are sewer systems that were designed to convey domestic, commercial, industrial and storm water runoff through a single pipe system to a POTW.

• What are the risks associated with the discharge of raw sewage?

Most combined sewer overflows occur during and after periods of rain or snow. The discharges are usually diluted by precipitation runoff and then mixed with the flow from the receiving river, but the potential for health and environmental hazards is still present.

• What are the federal and state requirements for cities with combined sewers?

In 1994, the U.S. Environmental Protection Agency (EPA) adopted a Combined Sewer Overflow Control Policy designed to reduce and eliminate combined sewer overflows nationwide.

• Will it be expensive to reduce and/or eliminate combined sewer overflows?

The solutions a city chooses will depend on a variety of factors unique to the individual situation.

• Useful CSO Web sites

There are many guidance documents with wet weather information available on the Internet.