Project Spotlight: City of Berne Combined Sewer Separation and Hydraulic Modeling

The City of Berne recently finished constructing over $3.5 million in combined sewer separation collection system improvements. Improvements included installing new storm and sanitary gravity sewers ranging from twelve (12) to thirty-six (36) inches in diameter. The project is an integral part of Berne’s goal to reduce combined sewer overflows (CSO) and achieve compliance with their CSO Long-Term Control Plan (LTCP).

Significant pre-construction and post-construction flow monitoring and hydraulic modeling were performed as a part of this project. Through their sewer separation and modeling efforts, Berne was able to significantly reduce the size of their CSO LTCP required wet weather lift station and collection system improvements resulting in significant cost savings. For example, pre-sewer separation project estimates assumed a peak pumping rate of 15 MGD would be required. Post-sewer separation hydraulic modeling indicates that 7.5 MGD of pumping will be required, which is approximately a 50% reduction in peak flows.

For more information regarding the success of the City of Berne’s Sewer Separation and Hydraulic Modeling Project, please reach out Ben Adams, PE, Senior Project Manager or Brian Wilson, PE, Project Engineer & Hydraulic Modeler.