Collection System Cleaning and Inspection Services

Project Description: Tohopekaliga Water Authority (Toho) maintains approximately 1,346 miles of gravity sewer within its service area. Toho’s Collection System Action Plan calls for a tiered approach to identify and reduce the Inflow and Infiltration (I&I) that enters the collection system. This tiered approach starts with desktop analysis to identify lift station areas with excessive wet-weather runtimes. An inflow abatement program is initiated annually to address the areas with excessive runtime. Included in this abatement program are smoke testing and flow monitoring to identify potential deficiencies attributing to the I&I identifying scope for CCTV follow up. In addition to the Collection System Action Plan, scope may be driven by high consequence locations or road projects.
Toho is seeking to augment its own sewer cleaning and inspection capability with contractor services. These services would include EITHER OR BOTH sewer cleaning and sewer inspection services. Contracted services would primarily be used in heavy debris, high flow, and larger diameter mains or for collection system located in areas requiring maintenance of traffic (MOT) for cleaning or inspection work.
The annual condition assessment program scope will include approximately 150,000 linear feet. of collection system. Of this scope approximately 1/3 may be designated as high traffic or high flow.
Note that the contractor may be directed to only clean, only CCTV or both clean and CCTV gravity sewer based on the owner’s needs.