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Central Avenue Tunnel Inspection ServicesReuse of Existing InfrastructureNTH was developing alternatives for re-routing dry weather flow away from a failing slope and an interceptor sewer that was moving with the slope. While searching for geotechnical data near the Cuyahoga River, a City of Cleveland “Water Main in Tunnel (Out of Service)” was discovered and it appeared to cross the river just north of the Lorain-Carnegie Bridge.
NTH contacted the Cleveland Water Department (CWD) to request as-built drawings. The Central Avenue Tunnel as-builts indicated a construction date of 1915, with revisions in 1921. The drawings showed a 10-foot ID brick and concrete-lined tunnel with 10-foot diameter vertical shafts at each end. The tunnel was obviously hand-mined, and the mining progress was indicated for every day. In January 2010, NTH and CWD representatives successfully located two steel shaft covers. Both shafts were uncovered and measured 84 feet deep, the exact depth shown on the as-built drawings. No water main pipes were observed from the surface. NTH hired Lake Erie Diving, Inc. to inspect the Central Avenue Tunnel. The goal was to determine the condition of the tunnel and to confirm whether water mains were present. In May 2010, using a remotely controlled submarine camera, we successfully navigated the full 582 feet of the tunnel and observed both shafts. The tunnel was in excellent condition, with almost no deterioration or distress. The tunnel and shafts are open and clear, with no water mains or piping of any kind. It appeared the tunnel and shafts were left exactly as they existed on the day the tunnel construction was completed. The cost of constructing a new, 500-foot long 10-foot diameter tunnel underneath the Cuyahoga River could be somewhere in the range of $5 to $9 million dollars. |