Donohue, the City of Rushville, Indiana, and generator contractor Bowen received a 2018 Merit Award for engineering excellence from the American Council of Engineering Companies (ACEC) of Indiana. The award was made in recognition of the Cloth-Media Disk Filters for CSO Treatment project completed for Rushville Utilities.
This project included a new and innovative application of cloth-media disk filters (CMDFs) for combined sewer overflow (CSO) treatment followed by ultraviolet (UV) disinfection. The design consists of cloth-media disk filters with a 5-micron effective opening size for CSO treatment followed by UV disinfection.
The CMDFs were also designed to filter the secondary clarifier effluent and, with the addition of alum, are capable of achieving a total phosphorus effluent discharge below 0.3 mg/l. The combined WWTP secondary effluent and treated CSO flow was designed to meet the plant’s discharge permit limits. The new system was designed and constructed as a guaranteed savings project to minimize ratepayer impacts. Bowen served as the general contractor.
Chlorination is traditionally used to disinfect CSO wastewater; however, the growing awareness of the adverse environmental impacts associated with chlorine disinfection byproducts has led to increasingly restrictive chlorine residual requirements. UV disinfection is an efficient and environmentally friendly way to disinfect treated wastewater.
This award is made each year by ACEC Indiana to recognize an outstanding engineering achievement that demonstrates a high degree of merit and ingenuity.
Pictured above (left to right): Tracy Williams (Donohue), Les Day (City of Rushville Utilities), Mayor Pavey (City of Rushville), Matt Meyer (Bowen), Steve Gress (Donohue), Steve Nutt (Bowen), and Ryan Vevang (Donohue).