Hillsborough, NH, Cuts Flow to the Wastewater Treatment Plant in Half With Effective Pipeline Inspection Management
The Town of Hillsborough, New Hampshire, has prioritized the maintenance of their aging wastewater collection system, which includes 19 miles of pipeline, 2 pump stations, and a lagoon wastewater treatment system. Following Capacity, Management, Operations, and Maintenance (CMOM) regulations and using a sophisticated but user-friendly pipeline inspection management software, the town is successfully repairing and maintaining their century-old distribution system and managing the infiltration/inflow (I/I) that had plagued the pipelines.
In 2009, the Town of Hillsborough, ready to proactively address their infiltration/inflow issues, began working with contractor Ted Berry Company Inc. (TBCI) to implement their CMOM performance goal targets. The CMOM approach helps municipal wastewater operators reduce regulatory noncompliance and can help utilities optimize their use of resources by shifting
maintenance activities from “reactive” to “predictive”. One of Hillsborough’s CMOM goals was to clean and inspect a certain percentage of their pipe each year. And, according to Paul Dutton, Hillsborough’s wastewater treatment plant facility chief operator since 1992, “once you find the flaws, you’d better fix them!”
Although Hillsborough was progressive in the mid- 1990s developing a CCTV inspection program to record the interior of their sewer lines, there hadn’t been a standard way to transfer all video into a system that would give actionable intelligence and usable results. TBCI implemented a software system for Hillsborough, using PACP, to take years of CCTV VHS video and
digitize and standardize the inspections.
After about 1.5 years, looking for a software that would go beyond just organizing video footage digitally, the Town upgraded to PACP and MACP NASSCO-certified ITpipes. The software provider easily transferred consolidated footage and other collected information into the new software. Their new management software was critical to the success of Hillsborough’s ongoing rehabilitation program. Once the information is collected and securely managed, the software can create deliverables after work is performed, sharing information so engineers, treatment plant operators, owners, and others can review results. Filtering tools using PACP overall pipe ratings simplify this even further. With information easily available, Hillsborough prioritized their rehabilitation efforts, starting with projects that were easy, obvious, and less costly.
The town tackled those larger points of infiltration and leaks for about five years, with localized points of trenchless rehabilitation. Trenchless Sewer Replacement could be a particularly good option to repair the sewer line, especially if you want it to be less intrusive. In pipelines that were structurally intact, more than 40 cured in place sectional point repairs were conducted in locations where grade 4 or 5 defects were identified by the software. In pipelines with more widespread damage, other, more appropriate, methods were used. With the use of SmartTabs and ESRI GIS software, pipe bursting was deemed the best rehabilitation method on streets with schools due to volume of traffic, capacity of the pipe, and the extent of defects throughout the pipe segment: the proximity of the defective pipe to the school was clearly visible on the screen. Pipe burst ing was also used to replace 8″ vitrified clay pipe (VCP) on Mill Street for the same reasons. Dutton says the results were noticeable immediately.
Eventually, the town moved on to more significant rehabilitation and repair projects, including full pipeline rehabilitation, pipe bursting, and Ultraviolet (UV) CIPP projects. The Town of Hillsborough successfully conducted these improvements and repairs as a result of careful prioritization of their asset management. Chief operator Dutton is very pleased with the results: “The results for Hillsborough have been huge. Since we did the repairs identified by TBCI and easily located with ITpipes, our flows to the plant have been cut in half.”
Credits to: NASSCO Pipelines Newsletter, May 2017