Stormwater Management and I&I Prevention

Stormwater Management and I&I Prevention
Stormwater management team uses technology to remain NPDES compliant

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Custom curb inlet risers save time on mill and overlay

Problem: Rowe Construction was contracted to perform a mill and overlay of a 3-mile stretch of U.S. Highway 51 near Bloomington, Illinois. “The curb and gutter area was a little different,” says Ben Donovan, superintendent with Rowe Construction. “The Illinois Department of Transportation wanted a slope, from 2.5 inches at the edge of pavement down to 1 inch in the flow line of the gutter pan. And there were 42 grated curb inlets in this 3-mile stretch.”

Solution: An American Highway Products representative met with Donovan, and together they figured out a way to customize the catch basin risers. Risers were installed just prior to new paving, and took one man 10 to 15 minutes per inlet to install. “Most of that time was spent on grate removal,” Donovan says. “Some had been in place for years, and were really stuck.

Result: The project was completed in October 2016 and, when reviewed in winter, all risers had performed well with no failures. “We were able to pave right around them,” Donovan says. “It all worked out really well, and IDOT was happy too. We’ll certainly be using them again.” 888/272-2397;

Reservoir presents challenges to pipe repair project

Problem: Tomhannock Reservoir in New York is over 5 miles long and holds 12.3 billion gallons when full. Parts of the reservoir’s earth-filled dam date back to 1900, and being the only water source for the nearby city of Troy, draining the reservoir for repairs is nearly impossible. In early 2013, the dam’s bottom outlet was failing. The 310-foot by 60-inch riveted steel pipe was leaking and threatening collapse. Without access from the reservoir side, all work would have to be done from the diffuser chamber — a small space about 4.5 feet wide, 5 feet high and 12 feet long.

Solution: Staging constraints led Ryan Arold, vice president of trenchless at Arold Construction Co. Inc., to recommend CentriPipe from AP/M Permaform — a centrifugally cast concrete pipe technology that repairs failing pipe by inserting a spincaster into a pipe to spray thin layers of high-strength cementitious grout onto the pipe interior. Arold set up the spincaster’s withdrawal winch in the diffusion chamber and ran in power, air and concrete hoses from outside the dam, and through the 30-inch diffusion pipes. Substantial scaffolding was built to provide safe access to the outlets 10 feet above the ground. Dewatering was accomplished by slowing leaks with hydraulic cement repairs, and installing a sandbag and poly sheet cofferdam to hold back water for about five hours.

Result: The design called for a 1-inch application of PL-8000, the high-strength grout manufactured by AP/M Permaform. However a little over 1 1/2 inches was applied in a total of five passes to cover the thick bolt heads completely and ensure a long-lasting, water-tight, structurally sound rehabilitated pipe. 800/662-6465;

Liner system employed in brick manhole restoration

Problem: A brick manhole in Georgia had almost a complete loss of mortar and was in need of restoration due to corrosion from hydrogen sulfide. Primeline Products, an authorized distributor of CLADLINER products, was contacted by Carylon Corp. (Bio-Nomic Services) in order to complete the project.

Solution: To begin, the crew ensured that all leaks and water flow had ceased, then proceeded to prep the manhole. CLADLINER spray-applied and back-troweled over. To address extreme deterioration of the bottom portion of the manhole, CLADRESTORE was applied as a resurfacer. The industrial-grade, early high-strength, high-density cementitious mortar is an excellent rebuilding/restoration mortar suitable for aggressive environments. It has 250 times the chemical resistance of calcium aluminate and the simplicity of a cementitious liner with the performance of a high-build epoxy liner. It can be effectively used as a resurfacer and liner in a single, simple application and can be used in wet, humid conditions.

Result: A final topcoat of CLADLINER was applied, the structure was closed, and the material cured to deliver a long service cycle protecting against inflow and infiltration and the hydrogen sulfide environment for years to come. It allowed the city to repair rather than replace this brick manhole, saving time and money. 877/708-2523;

Epoxy resin used to coat deteriorating manholes

Problem: An April 2017 START Rehab project in Edmonton, Canada, required coating of 16 deteriorated manholes 94 1/2 inches in diameter that neck down to 47 1/4 inches.

Solution: LaFarge-Holcim used One-Step 3-gallon kits of hand-applied epoxy resin NPR-5305 from Neopoxy. The kit is easy to use since both parts of epoxy are preloaded in the same container. The product doesn’t require any spray equipment, just an electrical drill with a paint blade and a spatula.

Result: This application allowed for time savings during installation, easy-to-control coating thickness, low mobilization cost, less traffic disruption, a good quality coating, and cost reduction. 510/782-1290;

Deep, century-old combined sewer pipe repaired with minor surface disruption

Problem: The Milwaukee Metropolitan Sewerage District needed a circa-1906 combined sewer overflow pipe cleaned and its concrete repaired to stop groundwater infiltration, to prepare the pipe for use as a diversion overflow tank. With walls varying between 6 and 12 inches thick, it’s located 30 to 35 feet below the surface of busy Hawley Road Bridge on Milwaukee’s far south side. Near an outfall to the Menomonee River, the pipe is in the floodplain and had developed cracks every 45 to 50 feet from uneven settling of surrounding organic soils. Approximately 120 feet of it contained severe enough damage to require five different types of concrete and epoxy crack repair. The city was looking for a structural solution that would provide 50-year service life from the liner, using trenchless techniques.

Solution: Through constant client communication and the ability to work from original as-built drawings, Spectrum Contracting Corp. completed the project from Jan. 21 through May 20, 2016. Spectrum applied 900+ mils of Sprayroq SprayWall, with quick curing time allowing crews to move fast and the pipeline to be almost immediately returned to service after final site cleanup.

Result: Spectrum achieved the desired inflow and infiltration elimination and extended service life, and completed the project on time and on budget, despite a myriad of significant safety, environmental, traffic and schedule challenges. 800/634-0504;

Stormwater management team uses technology to remain NPDES compliant

Problem: In July 2015, Alpharetta, Georgia’s Department of Public Works Stormwater Division had been awarded a $29,100 federal EPA grant to be used for field inspections of 130 miles of stormwater pipeline (7,486 pipes) and 8,344 storm structures, to identify potential hazardous conditions. However, the city’s decade-old pipeline inspection equipment and software was out of date. The city needed a rugged, steerable camera and transporter with the power and mobility to move around and over obstacles in the pipe. Its software had to provide digital video upload capability, so reports included important details that could be integrated into the ArcGIS stormwater structure and conveyance database, allowing operators to accurately add information — including PACP attributes — about pipes being inspected.

Solution: After bids and demonstrations, Alpharetta chose a new pipeline inspection system from TrioVision Technologies, including the Cobra Technologies V9 pan-and-tilt zoom camera, a model 806 steerable crawler, a cable reel and 1,000 feet of cable, and Cobra’s Asset DMS software.

Result: The city remained NPDES compliant, and the thorough inspection and maintenance program has allowed the department to stay out ahead of maintenance needs, including identifying opportunities to use trenchless technologies to avoid opencutting. 800/443-3761;


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