Successes and hitches in recent water pipe pigging

District engineering manager Don Hounsell presented his report of the water pipes swabbing process to council on Nov. 3.

District engineering manager Don Hounsell presented his report of the water pipes swabbing process to council on Nov. 3, highlighting successes and hitches.

He mentioned that the project came under budget by $27,000 or 17 per cent despite having to repair a water main and two valves.

“Which was very good considering the age of some of our infrastructure,” Hounsell said.

A caveat here is that not all lines were cleaned and swabs are still stuck within the lines for future extraction.

Hounsell mentioned the cleaning removed large amounts of debris from pipes, showing a video with brown water coming out of the pipes that eventually turned clear. He also showed a container full of black-coloured sediment similar to ground coffee.

A map he showed highlighted the area around the Northwest Community College, south of the mall and the pipes around Jewel and Gillespie Roads as having swabs stuck within the pipes.

“There’s two areas in our system where we have these stuck, because of the design there are some areas where there’s corners or things that it will not go around,” Hounsell said. “They don’t affect our water system.”

In his report, Hounsell stated that public works will extract the swabs once they determine where they are, and fix the pipes so that future jams do not reoccur.

Some water pipes did not receive cleaning because of design problems such as dead-ends that disallow extraction of the swabs, areas where cleaning would damage fragile pipes, and sections that experience high water flow.

“The worst areas that we had is downtown, north side and the industrial park,” Hounsell said.

Hounsell suggested that if the town wanted these lines to undergo cleaning, they needed to make further investment into pipes so that public works could extract the swabs.

After Hounsell’s presentation, Coun. Tom Stringfellow asked why pipes led to dead-ends.

“When they designed the water system here, instead of following conventional design of looping, or having a blowout system, they just dead-ended because they thought, ‘Well, in the future someone is going to come in and loop this,’” Hounsell said.

Coun. Tim Anderson asked Hounsell about Facebook posts about dirty water.

“The extremely dirty water on Facebook is in a private development, which is the trailer park. We cannot pig on private property,” Hounsell replied.

The cleaning process, technically termed “pigging”, started in Sept. 22 and ended on Oct. 3.

Hounsell’s report mentioned that water pipes needed cleaning in preparation of the commissioning of the new water treatment plant. Previous interviews suggest that cleaning is needed so that dirty water does not enter pipes again after the treatment plant goes into operation.