OSIS Augmentation and Relief Sewer (OARS)
Columbus, Ohio, USA
The City of Columbus had outgrown the capacity of its sewer system infrastructure. The changes to the original sewer system, known as the Olentangy Scioto Interceptor Sewer (OSIS), will reduce Combined Sewer Overflows (CSOs)—thereby reducing impact on the local Scioto River. Thinking in terms of preserving natural resources, city leaders also desired the critical ability to transfer one billion gallons per year of CSOs to two wastewater treatment plants servicing the community. City leaders put their trust in H.R. Gray to manage the project to completion.
Improving the system’s capacity involved creating a 23,000-foot-long-tunnel with a twenty-foot diameter. The new tunnel—part of the overall solution named OARS—will collect the overflow normally emptied into the Scioto River. A pump system empties the tunnel directly to local wastewater treatment plants, maximizing their usage without exceeding capacity. The new system also brings financial benefits in the form of lower costs over the long-term.
The OARS project reduces CSOs by ninety-seven percent per year. Fewer CSOs means the city will be aligned with the State of Ohio and EPA standards for reducing impact on the Scioto River. The OARS project demonstrates Haskell and H.R. Gray's continued commitment to helping municipalities protect the environment through conservation and sustainable practices.