Corroded Steel Watermain
Tuberculation in a Steel Watermain

This post is not about farm animal rights, or some cruel porcine-based Japanese reality TV game-show. Check out the video above for a glimpse of the power of a technology recently introduced into the North American Market from the UK.

It’s not hard to see from the video above that the pipes are getting cleaned by this process, but why is this technology so exciting? Because traditional watermain cleaning methods such as flushing rely on frequent applications to ensure minimal buildup between applications. The trouble is that most older watermains have not been adequately maintained over their lifespans, and would require traditional pigging, which can be a laborious and costly process that requires caution or the process may damage the pipes that are being maintained.

Aging watermains are extremely difficult to maintain for several reasons:

  • Watermains are underground, without surface access such as a manhole for inspection. Any issues typically require excavation, often within the road right of way.
  • Watermains can be up to 10 feet deep, depending on alignment challenges and needs.
  • Watermains are under pressure, any maintenance must work with and overcome this pressure, or the line must be drained to do work.
  • Water networks rely on continuous pressure and looping to ensure water quality and quantity, taking one section of watermain offline for maintenance must consider the implications for the rest of the network.
  • Watermains can be subject to biofilm and tuberculation which when unmaintained can cause quality and pressure issues and may contribute to corrosion of metal pipes. This material, when cleaned from inside the pipes needs to be flushed from the system to ensure high quality potable water.

Finding an affordable and effective means of cleaning watermains has been a struggle for water utilities, there is potential for ice pigging to become a standard technique for utilities to incorporate into maintenance practices for watermains. I’m not a huge fan of promoting a company I know nothing about, but the technology looks interesting and it would be worth reviewing case studies and determining the cost of mobilising and contracting this work within your area. The North American company licensed for the technology is the Utility Services Group. In the UK, the contractor is Aqualogy. This technology is not available in British Columbia, Canada yet.

Published by Mike Thomas

Mike Thomas P.Eng. ENV SP, is the author of and Director of Engineering at the City of Revelstoke in the Interior of British Columbia, Canada.