Wessex Water

Increasing flow rates in rising sewers

Jul 2021

Wessex Water approached SUEZ to carry out Ice Pigging™ at three sewage pumping station sites where suspected build-up of deposits in the rising main had been causing low flow rates. Each rising main was small in diameter, at DN50 or below, and other methods had failed to make sustained improvements.

Ice Pigging™ was applied at all sites without requiring any permanent enabling works. Pre and post Ice Pigging™ flow readings were provided by Wessex Waters on site flow meters. Significant improvements were seen at all the locations, both in terms of overall max flows and the average Dry Weather Flow. The average Dry Weather Flow increase following the Ice Pigging™ was 80%.

“We were really pleased with the results of these operations; the flow increases at each site means that we no longer need to run tankers from these stations during bad weather. We are sure that this technique will be useful at a number of our other sites.” Ashley Pratt, Wessex Water

“Ice Pigging™ is a great technique for the wastewater industry. It has proven to be very effective at improving flow rates on small diameter rising sewer mains. Because the process generally requires no enabling works, this is a very useful tool for operators of rising sewer mains that are struggling to reach their discharge consents.” Phil Pettit, SUEZ