Rushville Utilities, Donohue & Associates, and generator contractor Bowen received an American Council of Engineering Companies (ACEC) Indiana 2018 Engineering Excellence Merit Award for the Cloth-Media Disk Filters (CMDFs) for CSO Treatment project. 

This first-in-the-nation project included the new and innovative application of CMDFs 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. With the new UF disinfection system, the average monthly e. coli colony count for filtered plant effluent is less than 1. 

Sustainable benefits of this project include the reuse of existing 43-year-old structures that were repurposed and now house to the new treatment processes, which sustainably reduced the overall project costs.

As a result of the improvements, the application of the cloth-media disk filters reduced the capital cost for treatment of CSO discharges by approximately 25% and provides a viable option to the previous IDEM approved CSO storage tank technology and various types of high rate clarification processes for CSO treatment. 

The improvements were designed and constructed as a guaranteed savings project utilizing SRF financing.  This approach reduced the construction cost and project duration. The cost savings allowed the Utilities perform additional needed facility rehabilitation work at the wastewater treatment plant.

This successful project allowed Rushville Utilities to meet their CSO compliance schedule five years in advance and future lower phosphorus discharge limits three years in advance.