City officials are weighing options to strengthen a key water main for the long term — including building a new one — after a June rupture forced Calgarians to cut their water use and further inspection found more weaknesses.
Earlier this week, Mayor Jyoti Gondek announced that an analysis had found 16 trouble spots on the more than 10-kilometre pipe in northwest Calgary. She said it must be shut down starting Aug. 26 for about a month so it can be dug up and reinforced with concrete in those areas.
“Teams have identified that spring maintenance could add further reinforcement through the installation of a liner or a sleeve in that pipe,” Gondek told a news conference Friday.
“Engineering teams are also looking at constructing a new replacement pipe alongside the existing one.”
Michael Thompson, the city’s general manager for infrastructure services, said there are two other feeder main projects already in the works to adjust to Calgary’s growing population.
A new pipe north from the Bearspaw Water Treatment Plant is in the design phase, with construction to begin next year, and a new line to the south is in the planning phase. There are also plans to expand capacity at the treatment plant.
“Redundancy is important as it allows us to take the existing feeder main out of service while limiting the impacts to Calgarians and our customers,” he told the news conference.
The water use restrictions had mostly been eased when, on Wednesday, Gondek announced the looming pipe shutdown. That will mean the return of more onerous measures, including a ban on watering lawns and a request for shorter showers and fewer laundry loads.
The renewed restrictions are not expected to affect businesses like pet groomers and salons that rely on indoor water use, and Gondek said city officials are working with business that rely on outdoor water to find ways for them to keep operating.
Officials have also begun talking to residents and businesses along the roads that are expected to be dug up for the upcoming repair work.
“We absolutely understand that there is a great deal of inconvenience involved in this and we are weighing this against the need to ensure that we don’t face another failure and we don’t face running out of water,” said Gondek.