Small Municipalities Can Benefit From Equipment Rental and In-House Labor

A Pennsylvania township’s affordable DIY culture is inspiring other small communities.

Small Municipalities Can Benefit From Equipment Rental and In-House Labor

Anthony Caroline (left) and Dane Rose, use a Vactor jet-vac truck to clear a sewer line before running a camera to inspect.

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Penn Township in Pennsylvania was established in 1855 and its sewage authority 100 years later. Today, with the oldest of the sewage authority’s existing pipe dating back 50-plus years, much of the stock needs updating. Stanley Caroline, authority manager, has a plan on how to accomplish the task. It’s called do it yourself.

Perhaps never has DIY been advocated so strongly by a sewer official as it is by Caroline.

“I went to the board in 2012 and said I would like to do pipe bursting in-house with our employees,” Caroline recalls. “The board was very reluctant. They weren’t sure the crew could handle it. I said, ‘I know we can do it.’”

A combination of factors fed Caroline’s confidence. Pennsylvania’s founder William Penn wrote that “experience is a safe guide,” and Caroline certainly brings experience to help guide the process. He has been with the sewer authority for 23 years, beginning as an outside supervisor, so he knows the system. Just as important, he has a good understanding of construction work. “My background is in construction. I knew our guys could do what we needed to do. We have a very good crew, plus a lot of it is project management.”

Caroline says each round of pipe bursting at the authority is well-thought-out. “We know where we will be working next and which method of replacement we’ll be using. We’re basically going to be digging an entry pit, an exit pit and pulling new pipe — and it’s all figured out ahead of time here in the office.”

Early disappointment battling I&I

The Penn Township Sewage Authority crew was exposed to pipe bursting in 1998 when a pilot project was authorized by the board and contracted out. While the work appeared to be successful, Caroline and the board were not yet ready to jump onto the trenchless bandwagon. That stemmed partly from disappointment at the authority’s first encounter with the technology.

In 1994, the state Department of Environmental Protection had called out the sewage authority in Westmoreland County for chronic inflow and infiltration issues. The leakage largely stemmed from improper bedding of pipe decades before, according to Caroline. “Back in the day, they laid the pipe right on rock and it would crack. Sometimes when they hit a rock, they’d just bend the pipe up and over it.” In response to the DEP’s complaint, a pipe lining project was undertaken to replace the worst of the leaking pipe.

Some 10,000 feet of 8-inch pipe was lined, and the project appeared successful. However, a CCTV inspection of the lined pipe a few years later showed the lining had pulled away from the walls of the pipe and water was filling the space between the pipe and liner. The water eventually found its way to the treatment plant, defeating the whole purpose of lining the pipe. Whether it was product failure or faulty installation wasn’t immediately clear, but the experience soured the authority on pipe lining.

“It was the fastest way, but it just didn’t work out,” says Caroline, who returned to the tried-and-true opencut method to fix his underground infrastructure. His crews dug away for more than a dozen years, moving lots of dirt and successfully replacing the oldest of the leaking pipe.

In the meantime, video inspections showed that the pipe bursting project from 1998 continued to retain its integrity against groundwater. The new pipe was performing as advertised. So, 14 years after that pipe was laid, Caroline became a believer in pipe bursting and approached the sewer authority board with his proposal to have his crew start doing it.

How it works

TT Technologies, an Illinois company, supplies the machinery for the bursting. For the initial project in 2013, the company rented to the sewage authority a pneumatic pipe bursting unit. With it, Caroline and crew replaced 1,600 feet of 8-inch terra cotta, along with eight manholes and 20 connecting taps. The pipe was 12-20 feet deep and ran between houses and, in one instance, under a home addition. “If we’d done the work using the traditional opencut method, we’d have created a lot of very expensive problems,” Caroline says.

With that project, the pattern was established: Caroline’s crew would do the bursting and TT Technologies would supply the equipment. So it is that six years after its first bursting job, Penn Township Sewage Authority is still renting pipe bursting machinery and will continue to rent it each construction season for the foreseeable future.

“It doesn’t pay to buy the equipment,” the manager says. “For each project, we know we will have, say, $10,000 in equipment rental. It’s a fixed cost we budget for each year. The equipment is very expensive. Besides, the technology keeps changing so by renting we always have the latest technology.”

An example of changing technology is the difference between the in-house crew’s first pipe bursting project and later ones. The 2013 undertaking used a pneumatic pipe bursting system, which was effective in cracking open the old terra cotta pipe and inserting new PVC stock of the same diameter.

However, the Penn Township system also contains ductile iron, which doesn’t split apart as easily. So, TT Technologies now provides a hydraulic-powered Grundoburst static bursting system that employs rolling cutters in the bursting head to split iron or steel pipe. The 800G model that Penn Township typically rents tugs the head through the line with 200,000 pounds of pullback force.

“We haven’t tried any cast iron yet, but we’ve gone through terra cotta sections where there is 15-20 feet of PVC replacement pipe in the middle and the roller head just splits whatever is there,” Caroline says. He adds that his crew easily mastered the bursting routines after training by TT Technologies technicians. “They explain what you need to do every step of the way. It’s pretty simple.”

The team also has learned to dig an access hole at a manhole in the middle of a stretch of bursting. Rather than dragging in an entire 300 feet of replacement pipe — which can inconvenience a neighborhood — the crew sends the bursting head one direction and pulls in the line, then turns the machine around and bursts pipe in the other direction. “Once you get down there at pipe level, you want to do as much as you can from a single location and disrupt a neighborhood as little as possible.”

As for excavating the launching points for bursting machinery, the sewer authority owns the necessary digging equipment. Late model Bobcat E55 and E80 excavators make short work of digging the holes with a Bobcat T250 skid-steer and Caterpillar 426 backhoe moving pipe and performing the finer earth-moving tasks. Also in the equipment yard is a Vactor 2103 combination hydrovac truck with a 500-gallon water tank and 500-gallon debris bin for cleaning lines and pump stations.

In every case, Caroline replaces burst pipe with one of two types of PVC. Most of the new pipe is CertaFlo (CertainTeed) restrained joint PVC, which has a lockable joint system. It is inserted in 10-foot sections. Up to 380-foot segments of restrained PVC have been pulled into place. The other product used is fusible PVC, which permanently joins the pipe ends instead of employing CertaFlo’s gasket and locking ring connection. The fusible pipe is commonly used when a pipe is being replaced under or near a stream.

An affordable process

The sewage authority budgets to replace 1,500-2,000 feet each working season from April to October. All seven members of Caroline’s crew labor on the replacement projects, four or five at a time. So far, 2 of 9 miles of pipe — 8, 10 and 12 inches in diameter — have been burst and replaced. All this ongoing work is beginning to be noticed by surrounding townships.

“We have a lot of people calling and asking questions. People are wondering what we’re doing,” Caroline says. “Many are considering pipe bursting projects but probably will sub out the work, though that can add 60% to the cost. They’ve noticed that we’re doing the bursting ourselves and that it’s working for us.”

Last March, Penn Township’s in-house pipe bursting initiative was the focus of a TT Technologies presentation at the North American Society for Trenchless Technology’s No-Dig Show. It was well received.

Caroline is convinced many other small sewer system organizations would benefit from following Penn Township Sewage Authority’s example of incrementally fixing I&I problems. “There are a lot of small communities with, say, 1,500 customers facing $5 million worth of work. It’s daunting. But if they did 1,000 feet a year for 20 years, they would replace 4 miles of pipe. Just saying, ‘We can’t afford it’ and putting off replacing the pipe is not a solution.”

He advocates doing the work in-house whenever practical to avoid overhead costs. The township has a consulting engineer, but Caroline only consults him when absolutely necessary. “The pipe already is there. It runs from point A to point B. If you run a camera through it, you can plainly see what you’re getting into.”

So, Caroline and his field supervisor determine which sections of pipe are most in need of repair, sending an Aries Industries Badger pan-and-tilt camera into the pipe for close-up inspections. The men work up project details, call TT Technologies for a machine and set the crew to work. All of that avoids engineering fees, advertising bid costs, prevailing wage considerations and posting a bond for the job. “That really adds to the cost of a project,” Caroline says. Authority crew wages, incidentally, are 5% above union scale.

And, of course, Caroline recommends renting the bursting equipment along with any other needed machinery. “Little communities may not have an excavator, but that doesn’t mean they should put out a project for bid. Rent an excavator and an operator, and let your in-house crew do the grunt work. It makes a project affordable.”

His last recommendation comes from a voice of experience. “Realistically, people have to understand that they are never going to get a sewer system that doesn’t leak. They should work toward a high standard, but to say they will eliminate all the I&I, that’s not going to happen.”



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