Case Studies - Fall 2019

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Find Sources of Surface Inflow With Superior Smoke

Superior Signal smoke testing systems help reduce wet-weather sanitary sewer overflows and surface inflow. Superior Signal 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 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 used 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. 


Sewage authority rehabs, protects manholes with polyurea coating system


The Rostraver Township Sewage Authority in Westmoreland County, Pennsylvania, was struggling to find rehabilitation solutions for its aging sewer system. Time was of the essence, as streets and basements in one particular neighborhood were flooding during every precipitation event.


After receiving a sewer system rehabilitation grant, the authority chose OBIC Products’ OBIC Armor 1000, a multilayer, aromatic polyurea coating system, to rehabilitate several manholes in the affected neighborhood. It offers corrosion protection and chemical and impact resistance, even in subfreezing temperatures — an important consideration north of the Mason-Dixon Line. It’s applied in a multilayer process that forms a durable, seamless waterproof membrane, with high abrasion resistance for harsh environments. Advanced Rehabilitation Technology first power-washed the manhole surfaces to remove built-up dirt and debris, then grouted a few areas to stop leaks. Surfaces were then thoroughly dried with indirect heat dryers to finish preinstallation preparation. No bypass pumping was needed, and no surface disruption occurred.

Result: The installation took approximately three hours for each manhole, including prep work, with the total project completed in 2 1/2 weeks. “I was fascinated with the end result,” says Ann Scott, Rostraver manager, “in fact, with the ease of installation, the environmentally friendly product … the entire process.” 


Manhole cutter makes Hawaiian road repair more efficient


Major road construction companies like Grace Pacific maintain Hawaiian roads. These roads have an unusual amount of manholes and water valve structures, which present a problem for pavers. Most paving projects in the islands require milling the road before paving. The milling and paving are much easier if the manholes and water valve structures are removed and steel plated. This process allows the milling and paving machine to operate as if the structures are not there. Not having to work around these structures makes for a much smoother roadway.


Grace Pacific purchased the Mr. Manhole system for testing on the islands and subsequently made a second purchase. The company currently has two crews performing lowering and raising operations in conjunction with the paving crews. The crews have to maintain traffic during all operations so speed is very important. A typical lowering consists of cutting and pulling the manhole or water valve frame and placing a steel plate. The structure is GPS located, and after milling and paving, it is located and marked. The crews use the same cutting equipment to cut and restore the structure. The crews average about 25 minutes per structure to lower and about 30 minutes to raise a structure.

Result: Grace Pacific has completed 1,200 repairs to date with many more to come. 


Company stops infiltration easily with spot repair


When the Upper Saucon Township in Pennsylvania suffered infiltration in an 8-inch stormwater pipe, they inspected the situation. A leaking joint and small crack in the pipe were the cause. It wasn’t a big break, but since the pipe break was directly under a street in a residential neighborhood, digging up and replacing the pipe would have taken a significant amount of time and caused substantial disruption for the residents.


The township determined that for small breaks, patch repair was a suitable solution. The 4-foot spot was repaired using the ShortLiner system from Trelleborg Pipe Seals, consisting of silicate resin and corrosion-resistant fiberglass mats. Free of VOCs and styrenes, the silicate resin is odorless and completely harmless to users.

Result: The 4-foot repair went in easily and upon inspection, and the result was smooth. Infiltration was stopped and with it the cost of needlessly treating groundwater and stormwater at the plant. 


Adjustable risers keep manholes at grade


With a population of 66,000, St. Charles is Missouri’s ninth-largest city and was the state’s capital from 1821 to 1826. “We have old and new areas, which means we have a lot of odd-sized sewer structures,” says Cory Rackley, lead equipment operator. “Adjustable risers make it much easier to raise all these differently sized manholes to grade.”


Since 2008, Rackley has been using Pivoted Turnbuckle Adjustable Manhole Risers, made by American Highway Products, to raise manholes precisely to grade without excavation, significant traffic closures, and the need for equipment to lift and set heavy concrete rings. The riser is a sturdy, flexible, galvanized ring made with steel that uses a turnbuckle to adjust riser diameter. Installation is simple and fast; one man sets the riser in the original utility rims and uses a screwdriver as a lever to expand it to fit. Since the turnbuckle leverage applies thousands of pounds of force, the riser seats in the rim tightly, providing a new rim for the manhole with no rattling or looseness. When installed properly, Rackley has never seen one fail.

Result: At-grade risers are better for roads in many ways. They don’t set low, so water doesn’t collect around the manhole lid causing excessive infiltration; and they don’t set high, so vehicle tires don’t jar the lid and rim continually. And since risers are usually set just before paving runs, the newly raised manhole is surrounded by new, contiguous pavement, and that prevents water and freeze-thaw damage in the pavement around the manhole. 


Smoke testing employed on sanitary sewer with multiple I&I issues


As a member of the East Bay Municipal Utility District, the city of Berkeley, California, is currently under a consent decree to identify and remove significant inflow and infiltration from its sanitary sewer collections system. National Plant Services is under contract with the district to provide inspection and assessment services for all satellite communities. To provide sanitary sewer smoke testing services for the city’s Phase 7 work, National Plant Services contracted with BlueWater Solutions Group.


BlueWater conducted smoke testing on over 140,000 linear feet of sanitary sewer utilizing the 30-L Fluid Smoke System from Superior Signal. This smoke fluid system was essential on this project during the testing of several large-diameter gravity mains. Due to the available capacity within the mains, it typically took several minutes for smoke to emit from sources. In total, 102 I&I sources were identified, including 33 private and 69 public sources. The city has a private sewer lateral ordinance where any I&I sources identified on private property are required to be repaired.

Result: For each property where an I&I source was identified, a smoke testing return record was created and mailed to the property owner with follow-up instructions on how address the issue. Each return record included the property address, date and time of testing, photos of the front of the property with address, close-up photo and detailed sketch of the source. 


Constant root-intrusion problem fixed with CIPP solutions


The Family Plumber in Los Alamitos, California, had a longtime residential customer who was having a yearly issue with root intrusion. The city got involved, as the problem was spilling into the city sewer. A camera inspection determined that 75 feet of 4-inch cast iron was getting brittle and couldn’t handle more cleaning. The homeowner had two options: dig up the yard and be without water for at least a week, or reline the pipe. After consulting the plumber, relining the pipe was chosen as the best and most economical solution.  


The Family Plumber wanted to add CIPP as a service, and this was their first job. With Pipe Lining Supply’s trained technician, they did on-the-job training. They dug a small access point in the yard, using a Renssi high-speed cable machine with a 4-inch chain knocker to prepare the pipe. They then used a 4-inch green calibration tube as a preliner since there had been lots of rain and groundwater infiltrating the pipe. They used the Quik-Shot System, a portable 70 cfm compressor, 4-by-3-inch embossed liner, Quik-Pox 60 resin, and hardener. To cure the liner, they used the Quik-Heater. The entire job took four hours to complete.  

Result: After final city inspection, both the homeowner and city were impressed with the completed job. The homeowner saved money and helped ensure against roots in their sewer line in the future. 



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