The Department of Public Works in the Village of Owego, N.Y., planned to reconstruct Spencer Avenue and needed the 24-inch clay sewer line running beneath it evaluated. Wastewater Superintendent Ron Horton suspected that the 80-year-old pipe, one of the oldest in the village, had problems, but the amount of sand, grit, and gravel in it prevented an inspection.
Horton and his three-man crew spent 30 hours cleaning 300 feet of the line using a 62 gpm/1,000 psi floor-cleaning nozzle. “We were going nowhere fast, and we weren’t getting down to the bottom of the pipe,” he says. “We had to clean and televise that line so the DPW knew what to expect and could plan accordingly.”
Searching for a solution, Horton contacted KEG Technologies Inc. to demonstrate its floor-cleaning nozzle for 12- to 24-inch lines. Using an above-ground test rig, Horton saw the difference in flow characteristics between his nozzle and the eight-jet, 40 gpm/1,800 psi KEG nozzle.
Horton purchased one, enabling his crew to work seven times faster and meet the deadline. Based on their evaluation, the DPW will reline the combination storm and sanitary sewer with cured-in-place pipe before resurfacing the street this year.
Stubborn adversary
The Spencer Avenue line handles 40 percent of the flow from the village, and has three pump stations. A portion of the 2,100-foot pipe was cleaned in 1978 using drag buckets, but a sewer cleaning and inspection program wasn’t established until four years ago. That’s when the village bought a Saturn III pan-and-tilt camera on a Badger six-wheeled crawler from Aries Industries Inc., and a floor-cleaning nozzle.
“We couldn’t run the camera through the clay line because debris built up under the crawler and stopped it,” says Horton. “However, we did remove some car parts. I’m still shaking my head trying to figure out that one.”
When the KEG nozzle arrived, the crew worked manhole to manhole. The manholes were centered in intersections about 300 feet apart. They cleaned upstream 20 to 30 feet, then brought the nozzle back so as not to build up a dam that would block its progress. The streets were wide enough so that lanes remained open and traffic flowed around the work crews.
“We devoted four or five hours a day to the project, working mid-morning to mid-afternoon when the flow in the line was a little less and traffic was lighter,” says Horton.
Cleaning up debris
The village’s 2003 combination truck from Vac-Con Inc. powered the nozzle, which cleaned 70 feet in the 20 minutes it took to empty the 1,000-gallon water tank. Excess water in the 9-cubic-yard debris tank was directed back into a manhole. After the crew refilled the water tank twice, they had to empty the debris tank at the wastewater treatment plant. The crew removed 30.3 tons of sand, grit, and gravel from the line.
“The nozzle concentrates the flow at the base of the debris, lifting it up and allowing it to collapse from above,” says Horton. “It enabled us to stay on the job and move a larger volume of material. For example, we cleaned the entire line in 30 hours, but went only 300 feet in the same time using the old nozzle.”
The camera traveled unobstructed through the cleaned pipe, taking images of multiple longitudinal fractures, tops of broken pipes repaired with flashing and concrete, and other issues, but no root intrusion (the area has few trees). “We met our deadline and the reconstruction of Spencer Avenue is on course and on schedule,” says Horton.
