Ice Pigging: New Water, Sewer Pigging Method Offers Unique Benefits

Ice exiting the water main through the dechlorination box. It just shows how dirty the ice is after pigging operations.

The project was split into two runs. Work began just before Labor Day 2012. The first run of 9,500 feet was completed in about three hours. The second of 8,000 feet was completed in about 2½-hours two days later, the Friday before the long holiday weekend.

“Normally, a water main cleaning project wouldn't be scheduled prior to a Labor Day weekend due to the possibility of losing water service for an extended period of time,” said Ervin. ”However, the county believed the risks of a disruption were extremely low, and no disruptions to water service were experienced.”

County personnel cut out samples of the PVC before and again after the clean process.

“Inspecting the pipe samples showed that heavy, black manganese residue on the pipe walls was completely removed,” said Ervin. “As a result of the cleaning, customer complaints have been eliminated.”