Case Studies - Summer 2019


Find Sources of Surface Inflow With Superior Smoke

Superior Signal smoke testing systems help reduce wet-weather sanitary sewer overflows and surface inflow. Superior smoke candles, fluid and smoke blowers are designed to smoke test sanitary sewers quickly, efficiently and economically. The blowers can be used with smoke candles or fluid to detect sources of inflow and other faults. Smoke candles provide a highly visible smoke to find more faults at a longer distance. The Superior 3C Classic Smoke Candle produces a volume of 40,000 cubic feet of smoke in just three minutes. Multiple W3C Smoke Candles can be together to create larger volumes of smoke visible for longer periods of time. The company’s fluid systems offer a liquid-based alternative for mainline sewer inspection and feature a stainless steel injector to maximize dry smoke output, producing a higher-quality, liquid-based smoke. Superior Smoke’s testing techniques were developed over 60 years ago and are still made in the U.S. 800-945-8378;

Manhole risers install quickly and cost effectively


Home to Birmingham, and more than 660,000 residents, Jefferson is Alabama’s most populous county, and the local sewer network contractor Champion maintains includes 3,600 miles of pipe and 80,000 manholes. Though manholes themselves are durable infrastructure, they do need to be kept at grade. If they are set low, water collects around the manhole lid, causing excessive infiltration. If they are set high, they become a traffic hazard, jarring vehicle tires, the lid and rim continually.


Champion uses Pivoted Turnbuckle Manhole Risers made by American Highway Products. They are based on a simple concept: Tough, galvanized, flexible rings of steel are placed in old manhole rims and expanded with a pivoted turnbuckle (turned by hand with a screwdriver) that exerts thousands of pounds of force. This sets the riser tightly and precisely into old rims, even if they’re worn or out of round.

Result: They’re quick and easy to install in five to six minutes, according to Champion. They are safer for crews due to their relatively light weight and are cost-effective compared to jackhammering and manual lifting. And they have a good track record. Champion keeps them in stock and has been using them for at least 18 years.

Joint seal system eliminates infiltration and soil erosion


In May of 2017, the Michigan Department of Transportation discovered pavement failures in the westbound lane of Interstate 94 in New Buffalo near the weigh station just inside the Michigan border. Further investigation revealed that a 1,000-foot, 72-inch reinforced concrete pipe conduit under the interstate highway had joint separation issues, which were allowing the very sandy native soil to migrate into the pipe, undermining the roadway bedding above. Engineers consulted with the American Concrete Pipe Association to come up with some options for repairing the joints. 


The engineers were referred to Cretex Specialty Products, which assisted by recommending the Cretex HydraTite Internal Pipe Joint Seal System. In early June 2017, a site visit by Cretex representatives was conducted and the number of seals and appropriate seal widths were determined by walking the pipeline and physically inspecting each joint. The Michigan DOT was in an emergency to complete the repairs, which consisted of pipe-joint seal installation and grout injection from the surface to help stabilize the soils around the pipe. The job bid on July 7, 2017. A large underground utility contractor was awarded the job, and construction began Aug. 21, 2017. The surface prep and installation teams completed the installation of the 115 joint seals in approximately one week.

Result: A punch list required retightening a small number of seals found to be still leaking, but once that was competed, all joints had been sealed. The ground stabilization grouting was completed, the pavement settlement has stopped and the life of this conduit has been extended by many years.

Mortar used on huge manhole repair job 


The Los Angeles County Sanitation District needed to stop infiltration, restore structural integrity and protect against corrosion in its manholes.


National Coating & Lining Co. used Strong-Seal High Performance Mix from The Strong Co. to repair these manholes. It is a 100% pure-fused calcium aluminate mortar. In addition to stopping infiltration and restoring structural integrity, this cementitious liner is specifically designed for protection against microbiologically induced corrosion. The company rehabilitated manholes owned by Los Angeles County in Lancaster, Monterey and Rancho Palos Verdes in March, April and June 2018. In Lancaster, they repaired over 600 vertical feet (45 structures) as part of the Trunk “F” Sewer Rehabilitation job. In Monterey, they repaired over 200 vertical feet (16 structures) as part of the Monterey Park Relief Trunk Sewer Rehabilitation job. Finally, in Rancho Palos Verdes, they repaired over 130 vertical feet (16 structures) as part of the Monterey Plaza Trunk Sewer Rehabilitation job. 

Result: In total, there were 77 sealed, structurally sound manholes with maximum corrosion protection. 800-982-8009;

Lining system helps stop water infiltration at university 


A university had old pipe that needed extensive cleaning and also leaked, meaning it needed to be repaired due to health/safety concerns. After video inspection, the repair contractor could see they were having major infiltration problems, with leaking both at the joints and pipe. With manhole access, the contractor first tried to cap the pipe to stop the infiltration, but it still leaked, so relining the pipe was the best solution. The clay tile pipe was 315 feet long and 8 inches in diameter.  


This was a large job with over 485 pounds of resin. So, to make sure the resin cure was slow, the contractor ensured the right combination of mixing, temperature and sun control. It took 1 hour and 20 minutes to mix resin, wet-out the liner using a Quik-Roller and shoot it into the ground using the Quik-Shot system from Pipe Lining Supply. They finished the project by curing the liner by tapping into a nearby fire hydrant and using two Quik-Heaters running back to back to get the correct Btu.  

Results: After diagnosing the problem with a camera, using a vac truck to get as much infiltration out as possible, using a preliner, then shooting a new line and heat-curing it, the university has 315 feet of new pipe that is not leaking, and they did not have to dig up the campus. 888-354-6464;

Liner used to end I&I issues in precast manholes


Along one length of the Carroll County (Maryland) Bureau of Utilities’ sanitary sewer force mains, there are nine precast manholes. As with most aging municipalities, they required regular attention and rehabilitation in order to eliminate I&I through their leaking joints.


Pleasants Construction recommended Epoxytec’s CPP Sprayliner. This 100% solids, high-build epoxy paste is blended with fiber-reinforced polymers, providing high strength with flexural properties. The product was applied using an Epoxytec CPP Sprayliner rig. Materials flow through separate (part A and part B), continuously heated hoses. The system has a fixed ratio of 1-to-1 by volume. This structural product was sprayed to achieve a thickness of 100 mils.

Result: Applied by a four-man crew, the entire application to all nine manholes took five days. “When searching for manhole solutions, it’s important to find a product with hydrogen sulfide resistance and sealed I&I barrier protection,” says Ron Callahan, director of construction for Pleasants Construction. “CPP Sprayliner offers that protection in an easy-to-apply method.”

The successful application and completion of this project will eliminate I&I from these manholes, thus eliminating the costly routine maintenance that was previously required. 877-463-7699;

Micro detection technology employed in pilot study


Officials in Jefferson County, Alabama, sought a way to reign in inflow and infiltration losses brought on by major rain events.


A three-phase pilot project conducted by Duke’s Root Control and Eastech Flow Controls indicated there were multiple entry points for rainfall-dependent I&I in larger pipes and 8-inch lines comprising many of the microbasins. Most sites showed little or basically no response to what is considered to be a major 3-inch rain event, while two showed sizable increases during each rain event. With only 14 iTracker sensors, manufactured by Eastech and distributed by Duke’s Root Control, the technology was capable of monitoring and performing a full I&I analysis of 13 microbasins, plus a “microsegment” analysis of two of the 13 microbasins all the way down to a set of adjacent manholes.

Result: Evidence of major infiltration was discovered in a section of 15-inch pipe, with the majority located between two manholes. Cameras were immediately dispatched, and it was quickly determined that the large volumes of I&I were due to faulty laterals. They were quickly repaired. 800-447-6687;

Chinese city provided with speedy and efficient manhole repair tools


Being a bustling and fast-paced city, Guangzhou, China, needed a faster, more efficient way to handle manhole frame adjustments. Guangzhou is huge, with congested streets and an estimated population of 13 million people. Along with this, the city is home to a large number of manholes in roadways that require constant maintenance. Ultimately, Guangzhou contractors were in need of a manhole repair solution that happens very quickly so traffic can be restored as soon as possible.


Mr. Manhole had the opportunity to visit Guangzhou and train a large group of employees with a local contractor so they could properly use the Six Shooter manhole repair tools. The training took place using the Mr. Manhole Gold Series Six Shooter. The goal was to introduce this technology to the Chinese workforce and train them to quickly and efficiently repair manholes throughout China.

Result: By sharing Mr. Manhole techniques and technology, the Guangzhou company was introduced to a speedy and more efficient way of repairing manholes. Currently, the city uses a hinged manhole frame that swings open, and Mr. Manhole was able to develop a system to do this very quickly. Some of the manholes in Guangzhou also use a precast manhole frame and lid system. This method is unique to China, and Mr. Manhole was able to develop a technique to quickly adjust these structures to road level. Mr. Manhole also suggested Pamrex manhole frame and lid products for easy repair, as the frames have an easily removable lid compared to the pinned (nonremovable) lids on the Chinese models. Furthermore, Mr. Manhole also supplied the company with their Gold Series Six Shooter cutter for faster repairs. More training sessions are being planned. 419-741-9075;

Sealing products stop manhole leaks in minutes 


During a newly developed inspections program in the town of Ithaca, New York, infiltration was found throughout the system’s manholes. Joseph Slater, Water & Sewer maintenance supervisor for the town’s Public Works department, needed to find an economical solution for active leaks that could be handled entirely with in-house personnel.


PARSON SEAL-TITE and PARSON QUICK PLUG, both part of the manhole rehabilitation product line from Parson Environmental Products, were chosen because of their ability to stop active leaks in minutes. PARSON SEAL-TITE is a moisture-insensitive, two-component, fast-reacting hydrophobic polyurethane grout designed to stop high-volume active leaks up to 50 gpm. It is injected at or near the source of the leak, using a manual dual-component caulk gun. The product cures to a dense, rigid mass in approximately 30 seconds and contains no solvents, CFCs or HFCs. PARSON QUICK PLUG is a hydraulic cement material that is mixed with clean, potable water to produce an extremely rapid setting plug. It is inserted into prepared areas to stop active leaks under low to moderate pressure and is suitable for sealing around pipes and conduits.

Result: The products were able to quickly and effectively stop the active leaks, even in the most difficult areas on the bottom side of the pipe at the invert. 800-356-9023;

Liner system provides durable solution for aging culverts


In Ontario, the aging steel culverts under Route 401 had become a concern for the utility. Over time, sections of these culverts severely deteriorated due to their exposure to road salt. The throughway is adjacent to one of the Great Lakes in Ontario, and the water from the culverts runs into the lake. There were environmental concerns about the use of traditional cured-in-place pipe products due to the water-soluble chemicals within the resins that potentially could leach out into the water, causing harm to the aquatic life. 


Utility engineers in consultation with Municipal Sewer Services concluded that Thermoform from Warrior Trenchless Solutions was the best solution. It is a PVC-alloy, fold-and-form pipe liner that provides a durable solution, removes environmental concerns and has a long life expectancy. It is manufactured in a factory-controlled environment, with rigorous material testing to ensure it conforms to and exceeds the expected standards. It does not contain any water-soluble chemicals and therefore removes the risk of any pollution.

Result: Municipal Sewer Services, because of the durability of Thermoform, was able to rehabilitate culverts considered too high-risk for other materials. It provided a seamless, tight-fitting liner that increased the structural integrity of the culvert and prevented any further I&I. Following the initial successful installation, the Municipal Sewer Services and the utility have continued using Thermoform as their preferred method of culvert rehabilitation.716-601-7760;

Liner system helps wastewater plant avoid major shutdown


In 2017 the Rivanna Water and Sewer Authority was constructing odor control improvements at their wastewater treatment plant in Charlottesville, Virginia. The project included the installation of aluminum covers above several treatment structures, which were emitting odors. Before the concrete structures could be covered, a protective liner was to be installed due to potential corrosion caused by hydrogen sulfide gas. During the project, significant concrete deterioration that required repair was discovered in the primary clarifier distribution box. This posed a significant challenge to the design team since all of the flow coming into the wastewater plant passed through this critical structure, which could only be shut down for 72 hours due to the plant’s limited storage capacity.


Hazen and Sawyer was the design engineer and looked at several alternatives to make the repairs within the short shutdown window. Several coating contractors were contacted and none could repair the concrete and install the coating system in less than seven to 10 days. They contacted SpectraShield Liner Systems and sent them photos and drawings of the primary clarifier distribution box. SpectraShield determined they could complete the work within the 72-hour time frame using its liner system to rehabilitate the deteriorated concrete and protect the concrete from hydrogen sulfide gas. Crews worked around the clock and completed the work on time, allowing the wastewater plant to resume operation.

Result: Due to the fast and easy application, the distribution box was quickly repaired and lined, and a major plant shutdown was avoided. 800-284-2030; 


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