- ENGINEERING INFO
- CASE STUDIES
® DR25" />
Cape Fear Public Utilities Authority (CFPUA) recently completed an upgrade and expansion project at the James A. Loughlin Wastewater Treatment Plant that, in addition to process upgrades, increased the plant capacity to 16 MGD. An existing 30" force main, installed in the 1980s, discharged effluent to the confluence of the Cape Fear River and the Northeast Cape Fear River, but was limited by permit to 12 MGD. In order to permit the plant for the full 16 MGD capacity, an additional 30" parallel force main was contracted in April 2011. The alignment, installed via horizontal directional drilling (HDD), passes through a spongy Progress Energy right-of-way and under Smith Creek, generally paralleling the existing main.
Bid documents prepared by McKim & Creed allowed the entire 2,600 LF to be drilled at once or for the length to be installed in two sections. The general contractor, TA Loving, and its HDD subcontractor, Environmental Crossings, Inc. (ECI), opted to set the drill rig site in the middle of the alignment; enabling them to drill and pull in one direction, then rotate 180 degrees to drill out the second shot. Site complications included finding 1,200 LF of layout space for the Smith Creek shot, where the drill rod exited on a landlocked piece of land with restricted access. Close coordination between TA Loving, Underground Solutions, and CSX allowed that to happen without a hitch. The second HDD shot required pipe to be fused and strung along the existing pipe ROW, but the 1,400 LF, 30" FPVC® string had to cross over a CSX railroad siding during pullback.
Commenting on UGSI's construction management, Bill Bissette of TA Loving remarked, "What sets UGSI apart is their willingness to become part of the build-out as it affects their Fusible PVC® pipe. UGSI's construction manager, Walt Rountree, spent several days with our exit-side crew, lining up pipe and choosing pick points for the very challenging Smith Creek crossing. We appreciate everything he did to help make this drill go as well as it did."
|Pipeline Details and Project Summary|
|Project:||Loughlin Plant 30" Effluent|
|Pipe:||2,600 LF; 30" DR25|
|Pressure Test:||150 psi for 2 hours|
|UGSI Contact:||Gary Shepherd (804) 677-8950 email@example.com|
Fully appreciating the challenges, the owner was pleased with the project's success. Craig Lundin, P.E. and Project Manager for CFPUA, said, "Cape Fear PUA knew from the start that the HDD portion of this project would be most difficult to perform due to several challenging aspects. We made it clear through contractor pre-qualifications that we would be looking for a highly qualified team and would require their expertise once the work began. Fortunately, TA Loving, ECI and Underground Solutions provided the experience necessary for the challenge. The contractors suggested extending one drill and shortening another to reduce risk, which meant changing access points and coordinating with CSX Rail to allow the crossing during pullback. CFPUA worked closely with everyone to make that happen and the end results speak for themselves."