Shoreline Storage Tunnel Project, NEORSD
The Shoreline Storage Tunnel (SST) Project is part of Project Clean Lake, a $3 billion, 25-year program. NEORSD began the program in 2011 to meet the Clean Water Act standards and address water quality issues. Project Clean Lake will eliminate 4 billion gallons of wet weather combined sewer overflows (CSOs). Every year this waste releases into Lake Erie and its tributaries in the Greater Cleveland area.
The Shoreline Storage Tunnel Project is a 23-foot diameter storage tunnel approximately 14,100 feet. It is also the first phase of CSO control measures required at this location under Consent Decree Control Measure 7. DLZ led the CCTV inspection and condition assessment of 2,500 feet of sewer. That included repair recommendations for circular, egg, arch, and rectangular sewers ranging from 15- to 120-inches in diameter.
The primary focus of the sewer rehabilitation includes the assessment and repair recommendations for a 120-inch diameter circular brick sewer. This sewer also happened to have a longitudinal fracture in the crown. The existing sewer is critical for the overall success of Control Measure 7, which is to serve as a tunnel conveyance sewer to relieve 750 MGD of flow from the existing Easterly Main Branch Interceptor during the design rainfall event. It reduces the overall Control Measure 7 estimated construction cost by over $80 million by providing relief of the existing interceptor through the current sewer system. Rehabilitation of the existing sewer included an assessment of cost and overall constructability, including a variety of construction methods and materials.