ROMAG screen helps WWTP with CSO compliance

PROBLEM: Indiana's North Vernon WWTP had a Combined Sewer Over-flow (CSO) at its headworks. During rain events, excess stormwater over-flowed a weir and spilled directly into the Muscatatuck River. The City was faced with complying with the EPA's nine minimum control requirements for CSO's.

SOLUTION: The North Vernon WWTP, working with PDR Engineers in Lexington, Kentucky, designed a screening system to remove solids and floatables and comply with the EPA CSO legislation. The engineer collected information and issued a specification for the ROMAG Screen, a CSO screen available in North America through Waterlink's Separations Division.

The project bid, and ROMAG was selected by the successful contractor. The screen was the first of its type in Indiana, and after a complete review, the State IDEM Office approved the screen and issued a construction permit. The screen was installed in November 1998.

The ROMAG screen is installed immediately upstream of the plant's head-works. It is 9½ feet long by 13 inches high, and sized to handle a peak flow of 5 MGD.

Excess flows from the combined sewer system are screened by the ROMAG prior to discharge through the CSO and the Muscatatuck River. Screened solids are retained in the main sewer flow and are removed by the plant's headworks screen, which is located 50 feet downstream.

The ROMAG screen is automatic and low maintenance. A level sensor monitors rising or falling water levels and turns the screen on and off. The self-cleaning action of the screen is hydraulically powered.

This plant handles ADF of 4.76 MGD and a peak flow of 7 MGD.