Repairing Charlottetown sewers without digging up roads

'It’s more efficient and more convenient in so many ways that we would never go back'

Image | CIPP Lining Crew

Caption: A Clean Water Works crew working with robotics to assess and work in the pipes below city streets. (Randy McAndrew/CBC)

Charlottetown is spending $3 million to rehabilitate city sewer mains this winter, all without digging up roads.
They have hired Ottawa-based Clean Water Works to repair the main sewer lines in parts of two neighbourhoods, Parkdale and Brighton.
The company will be using a method of repair called cured-in-place pipe lining or CIPP.
"This doesn't disturb the asphalt or the surface therefore it can be done in the wintertime … and it doesn't impede traffic, it may slow down traffic to one lane in various places but it's a pretty slick process," said Mike Duffy, deputy mayor of Charlottetown.

Image | Signs for traffic

Caption: The cured-in-place pipe lining process is less disruptive then digging up and trenching city streets to repair the aging sewer lines. (Randy McAndrew/CBC)

It works by having a robot with a camera feed back information from the sewer to be lined. Measurements and calculations are done from that data.
Then a resin-coated felt tube is pulled into the sewer and inflated using either water or air.
When the resin tube hardens and cures, it seals up the cracks and damage with a seamless lining.
Duffy said it should add about 50 years to the pipe's life span.

Image | Mike Duffy

Caption: Deputy mayor Mike Duffy says the cured-in-place pipe lining project is the 'way of the future.' (Jane Robertson/CBC)

Then another robot goes into the pipe and cuts out the holes for the connections to the homes along the pipe.
All of it underground, all of it without digging up roads.

'Way of the future'

Some of the sewer mains are more than 70 years old with stormwater leaking in as cracks are formed from tree roots.
This is the first time CIPP has been done in Charlottetown but Duffy said it's not a pilot project.
"This is the way of the future," Duffy said. "It's more efficient and more convenient in so many ways that we would never go back, I don't think, to digging up every time there is a sewer line breakage ... unless it was such a magnitude that it couldn't be repaired by this particular process."

Image | Charlottetown City hall

Caption: Keeping stormwater out of city sewers is one of the reasons to reseal the pipes through this lining project. (Jane Robertson/CBC)

The project is budgeted to cost $2.5 million in Parkdale and $500,000 for the Brighton area. It includes the CIPP and replacing some damaged manholes in the areas.
Both repairs are expected to wrap up by July 2018.