By rosebell
A Granite-Super Joint Venture has secured a US$324.8 million contract to construct the Big Creek Tunnel in Ohio, US, as part of the Northeast Ohio Regional Sewer District’s Project Clean Lake programme.
The project involves construction of a 6.8km-long, 6m-diameter combined sewer overflow (CSO) storage tunnel in the Greater Cleveland area. Construction is scheduled to begin before the end of 2026, with completion expected in winter 2030.
Big Creek Tunnel Scope
Granite-Super’s scope includes the main tunnel and approximately 950m of ancillary tunnels, comprising adits, an overflow tunnel, a connecting tunnel and a dewatering tunnel.
The joint venture will also construct multiple shafts, diversion structures, gate and screening structures, gate control vaults, consolidation sewers and an overflow box culvert.
Associated works will include sitework, utility installations and restoration.
Tunnel to Capture CSO from 11 Outfalls
The Big Creek Tunnel system will capture and temporarily store a combination of sanitary sewage and stormwater from 11 combined sewer overflow outfalls.
Once operational, the tunnel is expected to prevent approximately 550 million gallons of combined sewer releases each year, helping reduce pollution entering Lake Erie and other waterways in Northeast Ohio.
The Big Creek project is the seventh and final large-diameter CSO storage tunnel planned under Project Clean Lake.
Project Clean Lake
Project Clean Lake is a US$3 billion, 24-year wastewater infrastructure programme launched in 2011 by the Northeast Ohio Regional Sewer District.
The seven large-diameter storage tunnels are designed to significantly reduce combined sewer overflows across Greater Cleveland. Collectively, the projects are expected to prevent approximately 4.5 billion gallons of CSO from being discharged into Lake Erie and other local waterways.
Granite-Super Joint Venture
The scale of the Big Creek Tunnel project reflects Granite’s experience in large-diameter tunnelling and shaft construction, according to Granite Tunnel Division vice-president Jim Nickerson.
“This is a major wastewater infrastructure project, and it will strengthen system performance and protect local waterways across Northeast Ohio,” Nickerson said.
Big Creek Tunnel Construction Schedule
Construction of the Big Creek Tunnel is scheduled to start before the end of 2026. The project is expected to reach completion in winter 2030, when the tunnel system will provide additional CSO storage capacity for the Greater Cleveland sewer network.
