Project Overview
The GLWA CS-166 Capital Improvements Program Implementation Assistance contract supports GLWA capital project planning, scope development, design, construction phase procurement and construction monitoring through task orders for specific projects. With the leased acquisition of the nine Combined Sewer Overflow (CSO) facilities and the Water Resources Recovery Facility (WRRF) from Detroit Water and Sewer Department (DWSD), GLWA set up a program to systematically repair and upgrade the CSO and WRRF facilities. The CSO Basin Structural Improvements Program is a capital improvements project focused on addressing the structural needs at all nine (9) GLWA CSO facilities. The WRRF upgrades include work at various tanks, primary clarifiers, and buildings at the facility. The CS-166 task order in support of the Structural Improvements Program is responsible for preliminary condition assessment, scope of work development, preliminary design, request for bid documentation, and oversight services for a design/build contract to implement the identified structural repair and upgrade needs at these facilities.
Project Scope
NTH is providing technical assistance to the CSO Basin and WRRF Structural Improvements Programs through preliminary structural inspection and needs assessment, scope of work development, preliminary design, bid assistance, and owner’s construction oversight services for all nine (9) GLWA CSO facilities. In addition, these services are being provided at the WRRF at Primary Clarifiers 17 &18, Complex A Sludge Thickener Tanks 1-6, Complex A Sludge Storage Tanks 1-6 and Complex B 9-14, The Admin Building, Chlorination and De-Chlorination Building, Aeration Facility, and Secondary Clarifiers B-Houses.
Each GLWA CSO facility has an aboveground operations/controls building(s) that typically house the facility controls, disinfection storage tanks, disinfectant dosage equipment, and screening equipment. Each CSO facility also has a below-ground basin component that handles the sewer influent overflow, disinfection mixing chamber, treated sewage storage, and treated sewage effluent to sewer outfalls. The facilities at the WRRF include above and below grade tanks, clarifiers and buildings of varying sizes.
NTH provided preliminary structural condition assessments for the facilities listed above. As part of our structural condition assessment NTH completed the following tasks and support activities: manned-entry confined space evaluation of basins, tanks and clarifiers including below-ground facilities, evaluation of building areas, mapping of defects, prioritization of repairs, development of typical repair recommendations and typical detail drawings, development of an engineer’s estimate of probable construction costs, and assistance with bid document development. NTH assisted in the analysis of the bids received and the recommendation of the most responsible design/build team for the projects. After award of the design and repair contracts, NTH assisted in the review of the design components, materials submittals, Request for Information, provided owner’s construction oversight services, and reviewed contractor invoices for accuracy.
During the construction operations, NTH assisted in determining the priority of the repairs to ensure the highest priority was addressed in the early stages of the repair contract. NTH site professionals were instrumental in identifying areas where the contractor team was deviating from the design specifications and coordinated between GLWA and the contractors so the procedures were corrected, and the repairs were done in accordance with the project specifications.
Client Benefit
NTH worked with the Owner’s Team to identify field issues and areas where the repairs were deviating from the specifications and assisted the team in implementing corrective measures and to prioritize repair scopes to ensure that repairs performed were of the most benefit to the long-term function of the facility.
