How Much Treatment Capacity Do You Have for Wet Weather Treatment at Your Existing Facility? A Successful Case Study for Stress Testing in Pontiac, Michigan

Over the last 10 years, the City of Pontiac has invested over 10 million in rehabilitating its sanitary sewer collection system. A remaining component of the operations plan was to understand the wet weather treatment capacity of the City's plant (primary and secondary treatment occurs at two locations) before a final operation plan was enacted. In addition, the City was completing an Enhanced Sanitary Sewer Evaluation Survey. The wet weather capacity was needed to determine if additional storage capacity would have to be constructed at the plant after cost effective inflow and infiltration were removed. The first objective of the stress test was to determine the wet weather capacity of the existing facilities. Studying the average treatment capacity was added as the second objective of the stress test due to additional improvements the City had made to the original facilities in the 1980s. Therefore, the purpose of the stress testing was to establish the average and peak flows of the Pontiac Wastewater Treatment Plant.