City of Toledo Downtown Storage Basin

The Downtown Storage Basin is the second largest project of 25 projects that make up Toledo’s CSO Long Term Control Plan (LTCP) for significantly reducing combined sewer overflows. This project is a critical component of the City’s LTCP as it addresses 7 of the City’s 32 CSO outfalls covered by the LTCP. When complete the new 17 million gallon (MG) storage basin will operate in concert with the City’s existing 6 MG Downtown CSO Storage Tunnel that came on line in the early 1990’s. Together these facilities will provide the required LTCP mandated level of control for the 6 CSO outfalls associated with the existing storage tunnel as well as enable elimination of the existing Magnolia CSO outfall.

In addition to the large capacity 17 MG storage basin and its associated dewatering pumping station, this project includes a 108-inch tunnel along water connecting the new storage basin to the existing storage tunnel and large open-cut diversion sewers from the Magnolia and Locust CSO outfalls to the new storage basin. The basin dewatering pumping station will discharge through a force main into the existing Westside interceptor located in Summit. Additionally the combined operation of the storage tunnel and the storage basin requires major modifications to four of the existing tunnel entrance dropshafts, located along Superior Street at Orange, Jackson, Adams and Jefferson, so that the higher volumes of combined sewage can be diverted into the existing storage tunnel and also conveyed to the new storage basin.

Construction of this project and its associated structures and sewers is challenging and requires the construction expertise of GSI’s staff members in deep excavations and protection of adjacent and nearby utilities, buildings and other important features. The basin is being built on property recently lease-purchased by the City from Norfolk Southern bordered by the Maumee River and Olive, Summit and Magnolia streets. The site is tight and is flanked by operating business, old buildings, an historical cobble street, the City’s primary operating salt storage facility and the river. Operations are conducted in a way that minimizes impact to adjacent structures and well as business operations.