Utility Service Group (USG) is demonstrating that Aqualogy’s ice pigging technology is more effective than traditional methods of pigging sewer lines. The most attractive benefit to wastewater operators is the extremely low probability of the ice slurry getting stuck. Traditional pigging techniques pose a huge risk of clogging lines. Two recent projects show that U.S. operators are becoming very comfortable using the technology in critical mains:
Over the past 13 years, the Town of Middlebury, Vermont, has noticed a decline in flow rates between their last pumping station and the wastewater plant. Unfortunately, they could not find a contractor willing to take the job due to the risk of getting a pig stuck. Ice pigging was selected as the best possible solution. The project required nine separate injections into the force main, which was accomplished using existing air valve stations. Following the injections, the flows in the pipe increased from 5.62 mgd to 6.26 mgd, returning the pipe to its original design capacity. The operator was very pleased with the results.
Western Hills Water District, California, has a 6-mile sewer pipe that splits into 12-inch and 14-inch diameter HDPE pipes underneath two separate aqueducts. Although pigging stations were installed during construction, the General Manager retrofitted the launching stations with flushing taps and flushed once a month instead of pigging. Flushing proved inadequate. Ice pigging removed 67 lbs. of sediment, which the district considered to be significant. After seeing the cleaning results from a pilot test with a 1,700-linear-feet section of pipe, the General Manager expressed interest in annual ice pigging cleanings.
These two examples demonstrate the successful use of Aqualogy’s ice pigging technology for cleaning U.S. sewer mains that proved either too risky or too costly in the past. The new ice age is upon us!