Emergency 30-in. Force Main Replacement
City of Fort Lauderdale, Florida, experienced a critical emergency in which several large diameter 30-in. sewer force mains were failing. This resulted in adversely affecting surrounding communities and waterways, leading to extensive and costly cleanup programs. The City issued an emergency response proposal request to replace and install new force mains.
Murphy Pipeline Contractors in association with DBE Utility Services and Chen Moore and Associates, collectively known as the Murphy Pipeline Contractors team (MPC) submitted a complete trenchless design-build proposal. The emergency trenchless design-build project represents one of the largest trenchless responses in North America in terms of complexity, pipe sizes, lengths, array of technologies and technical advancements. The compression fit HDPE pipe lining phases resulted in the longest continuous installation distance of a fully structural pipeline replacement solution in North America at more than 2,000 ft per pull. This was accomplished on three different installations.
To MPC’s knowledge, no other trenchless method has ever completed an installation at this distance for large diameter requiring a fully structural solution. Four phases were completed involving: Phase 1: 6,300 lf of 30-in. HDPE force main installed by compression fit HDPE pipe lining and HDD; Phase 2: 1,600 lf of HDD of 30-in. HDPE pipe in a highly urbanized area of downtown Fort Lauderdale; Phase 3: 6,400 lf of HDD of 30-in. HDPE pipe completed in two bores along Sistrunk Boulevard, one of the city’s main corridors; and Phase 4: 8,200 lf of compression fit HDPE pipe lining of 30-in. HDPE pipe in a highly dense mixed-use area.
North Area Interceptor Phase 9
Michels was the general contractor on a large-scale project to rehabilitate nearly a mile of deteriorating high-capacity regional sanitary sewer facilities that serve Fridley, Spring Lake Park, Coon Rapids and Blaine — the northwestern suburbs of the St. Paul-Minneapolis, Minnesota, metropolitan area.
The project included constructing a temporary conveyance system to maintain wastewater services throughout the duration of the project. The system consisted of three 30-in. sections of HDPE, each totaling 5,100 ft, to convey an average daily flow of 25,000 gpm of effluent and a peak flow of 52,000 gpm. Seven pumps were also installed on the system. Cured-in-place pipe (CIPP) liners were installed to rehabilitate 3,866 lf of massive 96-in. (8-ft) diameter pipe and 90 ft of 72-in. diameter pipe. The 96-in. CIPP segments were completed in four installations that varied in thickness from 25.5 mm to 34.5 mm and in length from 700 ft to 1,180 ft. Both 72-in. installations were 19.5 mm thick and 45 ft in length. The 96-in. segments were the largest diameter CIPP project Michels has completed, and included a substantial amount of work during Minnesota’s harsh winters.
The project also included rehabilitation of a meter station and manholes. There were eight 72-in. to 120-in. fiber reinforced polymer and concrete manholes installed on the project to replace existing manholes. Due to their large diameter and weight of resin, the CIPP liners were wet out over the hole (OTH) rather than being impregnated off site and transported to the job site. This required trucks to haul 730,000 lbs of resin to the site on days of installation.