‘Critical’ watermain break prompts no-dig order in Ottawa

Ottawa’s Infrastructure and Water Services Department is on emergency footing and has issued a “no dig” order along key watermains as it works to repair a “critical watermain break” near Fairmont Avenue and Highway 417.

The break occurred Nov. 14 within the Highway 417 corridor where contractors for the Ministry of Transportation are installing sound barriers near Fairmont and Young Avenues.

Article content

“The MTO sound barrier project team is working with the IWSD response team to investigate the break site to assist IWSD in developing our repair plan,” Tammy Rose, the department’s general manager, said in a Nov. 21 memo to the mayor and members of council.

“The city’s water system remains safe although the extent of the isolation has impacted overall resiliency of the system.”

The no-dig order was issued “out of an abundance of caution… to protect the water system resiliency,” Rose’s memo said.

The order includes several water lines in the downtown core, extends west along Richmond and Corkstown roads as far as Kanata, south on Woodroffe Avenue to Barrhaven, and roughly along the Airport Parkway all the way to Bowesville.

“Any proposed excavations which present a risk to the critical watermains will undergo a risk assessment and may be prohibited or in some situations may be permitted under strict operational constraints,” Rose said. “The no-dig zone will be reviewed and amended as additional mitigation measures are implemented.”

The Infrastructure and Water Services Department activated its Departmental Command Centre on Nov. 19 to co-ordinate communication. A day later, Ottawa’s Office of Emergency Management also began monitoring the situation.

Article content

“We are working closely with the MTO to develop and implement a repair plan that protects the province’s critical transportation asset and restores our water system to normal operation,” Rose’s memo said.

Last summer, the city of Calgary endured weeks of water restrictions after a catastrophic water main break. City officials have said that’s unlikely to happen in Ottawa because the city has two water treatment plants — one in Britannia and the other on Lemieux Island — that provide redundancy and are individually able to supply the city’s water needs. The city also has redundant pumping stations, one at Britannia and the main, 150-year-old water-powered pumps in the Fleet Street Pumping Station.