Nicholson Construction Co. will begin work on the Dugway Storage Tunnel (DST) as a part of an overall program by the Northeast Ohio Regional Sewer District (NEORSD) to control combined sewer overflows in the Greater Cleveland area. Nicholson will be installing secant piles as the temporary support of excavation for a baffle drop structure, as well as two rectangular gate structures across two site locations that will each connect to an existing sewer system.
The 24-ft diameter tunnel will be 180 to 230 ft below ground surface and stretch 2.8 miles from the Easterly Tunnel Dewatering Pump Station (ETDPS) to its upstream terminus at Superior Avenue. The DST will share the terminus with the Euclid Creek Tunnel and connect to the ETDPS. Following a storm event when treatment capacity is available, combined sewage overflow will be pumped from the tunnels to the Easterly Wastewater Treatment Plant by means of the ETDPS.
The project area is mainly residential with a few commercial properties and parks interspersed. Design work was completed by a joint venture of MWH Americas and Mott MacDonald. The general contractor for the $153 million project is joint venture of Salini Impregilo and S.A. Healy.
“Nicholson is installing one of the deepest secant pile structures in the city of Cleveland,” said Special Project Division Manager Russell Cooper. “The work will be technically and logistically challenging, but it’s the type of challenge Nicholson likes to take on.”
Upon completion, the combined Dugway Storage and Euclid Creek Tunnels will allow the district to store and treat 110 million gallons of combined sewage after each rain event, preventing it from having a negative impact on the environment. Nicholson expects to wrap up their work in fall 2016, and the overall project is scheduled for completion in 2020.
The North American subsidiary of Soletanche Bachy, Nicholson is a versatile geotechnical contractor specializing in deep foundations, earth retention and ground treatment.