The Metropolitan Sewer District of Greater Cincinnati (MSDGC) is implementing its Wet Weather Improvement Program through a series of projects or bundles to address combined sewer overflows (CSOs) and sanitary sewer overflows (SSOs) in different sections of its service area. As part of the Upper Duck All Bundle (UDAB) project, Wade Trim evaluated improvements to address 13 CSOs and 2 SSOs in the Upper Duck Creek Watershed. Integrated watershed planning was used to rightsize the combination of grey and green infrastructure needed to provide an annual overflow reduction of 2 million gallons.
After completing detailed modeling to size the improvements, Wade Trim developed an integrated stormwater and CSO solution plan for the watershed. The plan identified areas where green infrastructure could be used to reap community benefits and manage CSO and help achieve regulatory compliance. Planned improvements include strategic stormwater separation, relief sewers, CSO regulator structure rehabilitation, and an Enhanced High Rate Treatment (EHRT) facility. Green infrastructure solutions include stormwater wetlands, detention ponds, bioretention basins, stream day-lighting and removal as well as water quality treatment features. All of the improvement projects are planned to fit within the social and community fabric of the neighborhoods and therefore provide a Triple Bottom Line return on investment.
