The City of New Philadelphia, Ohio, like most municipalities across the United States, is constantly monitoring and repairing aged waterlines that spiderweb beneath the city streets.
However, a recent audit by the state found that one leak was losing more than 10 gals of water per minute. The audit also discovered that because of dozens of other leaks, the city was losing more than 300 million gals of treated water per year throughout its waterline system. The severity of the leakage and the imminent possibility of much larger leakage problems put the pressure on the City of New Philadelphia’s water department to speed up the repair process.
During the audit, acoustic technology was used to pinpoint the severity and location of each major leak throughout the city. Though workers knew where the leaks were located, many of the lines were laid years before digital mapping was a possibility. In addition, exact records of past repairs were not available, making each excavation a guessing game for the crews. Knowing all this, this meant that each dig by the crews could uncover inconsistent repairs that could be damaged by traditional excavating methods.
New Philadelphia Water Department Superintendent Kelli Ricklic explained that the use of hydro-excavating, or digging with water, has changed the game for his department and has brought a new level of efficiency and safety for workers. Workers are able to harness the power of water to reach leak spots, while never having to lift a shovel, he said, noting that hydro-excavating has also eliminated the fear of causing more damage to pipes in need of simple repairs.
Ricklic said that before hydro-excavating, traditional leak repairs began after crews cut the asphalt pavement and removed top layers of asphalt, brick and debris with a backhoe loader. To avoid damage caused by the backhoe forks, workers then entered the excavation site to hand-shovel around the water pipes and other utility lines that many times run parallel to the pipes. Workers also had to hand-dig under and around the pipe so that the appropriate leak repair could be made.
Hand digging not only is a very time-consuming and labor-intensive process, but while in the excavation site, workers expose themselves to various unknowns, such as damaged electric lines and cave-ins. By using this old process, a single leak repair can take a full crew an entire day to fix. Many workers have to be onsite for many hours, which in turn costs the taxpayers thousands of dollars per dig.
Benefits of Hydro-Excavating
Hydro-excavating has streamlined the repair process. Using a high-pressure water gun, workers blast through gravel, sand and heavy clay, all the while causing no harm to the utility lines. While the high-pressure water cuts through the rock and dirt, it also clears much of the mineral buildup often found on pipes that have been leaking for many years.
Another advantage of hydro-excavating is the ability to blast sediment out from under the pipe. This gives workers a convenient 360-degree area to work around the pipe. While one worker uses the handgun, another worker operates a large vacuum tube that continually removes the water and debris and deposits the sludge into a large tank. This process is not only easier and safer for water department crews, it is also much faster than the traditional methods.
Using Vacall’s AllJetVac 1215 — the latest in the line of Vacall combination sewer cleaners and hydro-excavators — New Philadelphia Water Department workers were able to address multiple problem areas in one day. On the first day, a AJV 1215 was used, enabling a four-person crew to locate three problem areas — two where they located valves and shut off leaking secondary lines and one where they repaired a main line. All three leaks were repaired in less than six hours — saving two days of work.
“The Vacall hydro-excavator saves us a ton of time,” Ricklic said. “It also keeps the work area safe by eliminating the need to work within the excavation site. Because the AJV 1215 cuts down the time that my crew has to be in the hole, the risk of workers being injured by a collapsing wall or damaging dangerous utility lines that often are located close to the water lines is nearly eliminated.”
Ricklic said the water department normally repairs about 50 to 70 major leaks per year and about five service leaks per month.
The hydro-excavating handgun and pump are capable of blasting water at 3,000 psi at 10 gpm. By using less water, the AJV 1215 is able to operate at a remarkable capacity while keeping excess sludge material to a minimum. This keeps workers working more and spending less time making frequent trips to empty the debris tank. A large, 1,500-gal capacity heavy-wall aluminum water tank also keeps workers on the job, reducing, if not eliminating, fill-up trips.
While the high-pressure water handgun breaks away material, the 8-ft, 6-in. telescoping boom vacuums away the sludge and deposits the material in the 12-yd debris tank fabricated with standard multi-stage airflow technology designed to increase machine life, reduce maintenance expense and soften noise levels. The powerful positive displacement vacuum utilizing an 8×24 blower constantly clears debris from the area so workers are able to monitor the leakage area while minimizing water and sludge buildup. Normally, workers would constantly be hand-bilging water that accumulates from the leak.
“If we do find a leak, the water will continue to flood the hole,” Ricklic said. “If they’re hand-digging, they also have to be hand-bilging. The Vacall was able to keep the work area clean making repairs more effective. With hydro/vacuum excavating, hand digging is eliminated and leaking water is not a problem for our guys.”
The AJV 1215 also is equipped with a standard front-mounted pivoting hose reel. The hydraulic debris tank tailgate opens for easy sludge dumping and cleaning. The debris tank also is equipped with an optional self-cleaning feature that blasts residual sludge from the interior of the tank making emptying and clean-up a simple task.
This article was submitted by Vacall Industries, New Philadelphia, Ohio.