The Village of Wheeling, Illinois, is no different from other smaller cities and villages in the United States when it comes to taking care of its underground infrastructure. Among the common challenges Wheeling leaders face is untangling the tree roots that have infiltrated their systems, which can cause structural and day-to-day problems.
Tree roots can be a huge headache if not proactively addressed and removed. The Village of Wheeling does just that with its successful chemical root control and sewer cleaning program.
“The overall condition of our pipes is good. We’ve done a lot of televising and investigating over the years and for the age of the pipes, in my opinion, they have held up very well,” says Wheeling superintendent of utilities Jeff Wolfgram, who worked for the Division of Utilities for more than 25 years.
Throughout Wolfgram’s career, he has seen Wheeling take a proactive approach to preventative maintenance of both its sanitary sewer lines and water lines, including exercising valves and inspecting buffalo boxes in search of leaks, Wolfgram says.
But roots are a different beast than routine cleaning as the damage they can inflict, if left untreated, can be severe in the pipes, as well as the residents’ lateral connections. With those concerns in mind, Wheeling decided to take action to halt any further growth in its wastewater pipes and turned to a chemical root control solution. That was three years ago and the results of the implemented program have been so good that Wheeling plans to continue with the program as it has made the work of its Division of Utilities that much easier today and going forward.
“The program is going really well and we are happy with the results,” says Wolfgram. “The proof is in the data.”
The data, Wolfgram notes, are the number of sewer backups and permits requested for private lateral repair work by residents (whose laterals were clogged with root intrusion) have been reduced by more than 50 percent over the last three years.
With a population of approximately 40,000, Wheeling is located in Cook County, in northern Illinois, situated less than an hour from Chicago. The village spreads over 8.75 square miles with the sanitary sewer system covering 5,600 acres, serving nearly 8,000 customers. The system includes 481,179 lf of gravity sewer main lines and 2,466 sanitary manholes.
Wheeling does not have its own sewage treatment plant. The village collects and sends its wastewater to the Metropolitan Water Reclamation District of Greater Chicago (MWRD), for treatment. Prior to 1955, most of the businesses and homes used septic systems and wells. After that, larger neighborhoods were being constructed, even more so during the 1960s and 1970s. “That’s when [the village] put in the sanitary sewer systems,” says Wolfgram, who has been with the Division of Utilities for more than 25 years. “During those times, it was predominantly made up of clay pipe. Eventually the clay pipe was changed over to plastic PVC pipe.”
But the majority of the sanitary sewer system — with pipes ranging in size from 8 to 36 inches — is still made up of vitrified clay pipe (VCP), followed by PVC, ductile iron and reinforced concrete pipe.
It’s those VCP pipes that require the extra treatment of chemical root control to make sure they remain clear of root debris that can cause serious issues to the system. Wolfgram describes the issues with root from “mild to moderate” in severity. “The roots were predominantly in the single-family residential neighborhoods that have large parkway trees. Those older subdivisions were built with the clay pipe and there are a lot of joints in them. Trees are pretty and everyone wants them but they don’t realize that those roots get in and find those cracks in the pipe,” Wolfgram says. “In a lot of cases, [the roots] will go in to the homeowners’ service lateral, which is private, and it’s very costly for them to make those repairs.
“Our root control program has definitely helped not only the village but the homeowners,” he says, “because the foam we use [to treat the roots] is migrating into the service laterals several feet. I know it’s helped them a lot.”
Without treatment, the roots were accumulating so much so that they were causing sewer blockages. “In some cases, they were also damaging the clay pipes to the point where sections would need to be replaced,” Wolfgram says. “A root cutter couldn’t get through the severe blockages. We had to replace the clay with PVC.”
The groundwork was laid for the program in 2014 when the village began gathering data about its system via flow monitoring to see how the pipes were performing. Afterward, the system was divided into basins and each was prioritized according to need. The basins marked at the highest priority underwent more intensive televising and smoke testing. Not surprisingly, the basins with the most need were those of the older VCP.
The Village let out the root control program to bid in 2017 and signed a contract with Duke’s Root Control to do the work. According to Wolfgram, Duke’s foams approximately 50,000 ft a year. The Village uses CCTV to televise the pipes before and after the treatment to record the results. “In addition to root foaming, our crews are out there on a regular basis high pressure jetting the lines,” Wolfgram says. “We have crews out all year long.”
Wheeling’s sewer cleaning program is an essential part of maintaining the underground infrastructure. The Village has two sewer cleaning units — one is a Vac-Con combination sewer system and the other is a standalone high-pressure jetting truck from Vactor— as well as an Envirosight CCTV camera system and WinCan software to televise and analyze the pipes. Crews on average cleaned about 75,000 ft a year over the last two years.
Wolfgram credits the combination of the root control program and regular sewer cleaning to continued reduction of sewer problems. “The foam was helping in the areas of heavy roots and a degreasing chemical that was applied while high-pressure jetting, helping in areas where there was heavy grease,” he says. “If the televising identified an area that needed the pipe to be replaced, we would do a point repair fix.”
Wolfgram also credits his crewmembers who have taken to the sewer cleaning technology and software to keep the program on track. He also notes that four of them have been PACP certified. But a lot of the credit, he says, goes to Village board who continually approves his requests for funding such products.
“We are fortunate that our village board is cooperative when we request money for infrastructure improvements,” Wolfgram says. “If we give them the information on how this will benefit our residents and businesses, they’ve been receptive.
“When residents pay their taxes, they like to think they are getting something for it,” he adds. “When they flush their toilet, they expect it to work. When they turn their faucet on, they expect the water to be there. We definitely take that seriously and try to provide them with reliable services.”