Efficient Control Improvements: Increasing the Use of Flow Equalization Basins

This hydraulic assessment identifies control improvements for three Flow Equalization Basins (FEBs) of a sanitary sewer network servicing the Northside Service Area of the City of Tulsa, Oklahoma. These facilities currently divert flow inefficiently with the result that their storage capacity is underutilized. The interceptor/FEB system was modeled in InfoWorks CS using Real Time Control (RTC) in order to evaluate alternatives for improving the FEB performance. The preferred control alternative consists of removing the existing weir from the diversion structures feeding each of the FEBs and replacing it with automated sluice gates. Local reactive control rules were tested to initiate the opening of the gates at the three FEBs in peak wet weather conditions. Modeled performance for three recorded and significant events show an average increase of 74% in volume stored in the three FEBs. The automated control allows shaving off of the peak flow going to the Northside Wastewater Treatment Plant (NSWWTP) and minimizes surcharging in the interceptor. This cost-effective control improvement involves added instrumentation/equipment and additional maintenance but will reduce operating costs and improve operational efficiency with minimal new construction.