WC138 SeptOct 2024 - Flipbook - Page 19
INFRASTRUCTURE
From Breaks to Fixes
Two researchers at Concordia University set out to collect
comprehensive data on the causes and conditions of
watermain breaks in cities across Canada.
BY REBECCA DZIEDZIC AND SADAF GHARAATI
S
WOOOSHHH! It’s not raining, but suddenly there’s water flowing down the street.
A watermain has broken. Canadians are no
strangers to watermain breaks and the impacts
they can have on their lives. On June 6, 2024,
a transmission watermain broke in Calgary, Alta.,
leading to a boil water advisory in the community of
Bowness. Because this main conveyed around 60 per
cent of the city’s water, widespread water restrictions
were implemented, impacting residents and businesses. Then, on July 6, 2024, a distribution watermain
broke next to the Glen Site of the McGill University
Health Centre, in Montreal, QC. Because of a major
drop in water pressure, that day all surgeries were
cancelled except emergency procedures, and ambulances were diverted.
Aging pipes and seasonal weather changes, along
with many other factors, have added stress to the
infrastructure of utilities across Canada. A 2023
study of U.S. and Canada water systems by the Utah
Water Research Laboratory found distribution pipes
experience 21.4 breaks/(100 km/yr) and transmission
mains 3.5 breaks/(100 km/yr). Because watermain
breaks can be influenced by a variety of interacting
factors, they are complex and hard to predict. The
usual approach to predicting watermain breaks
generally focuses on common pipe attributes or general protection strategies. Three key pipe attributes
generally considered are material, diameter, and age.
The type of material influences the failure mode. For
example, cast iron pipes are more likely to corrode,
creating holes in the pipe, whereas PVC pipes are
prone to scratches and voids, which lead to cracks.
Larger diameter pipes are generally thicker and able
to withstand higher pressures, making smaller pipes
more susceptible to failure. With age, there is an
accumulation of wear and environmental stressors.
Some important environmental stressors are related
to soil type and weather conditions, as these can increase movement and stress on pipes. The impacts of
Sadaf Gharaati
is a Modeler Specialist in Asset Investment
Planning (AIP) at DIREXYON technologies.
She earned a Master of Applied Science in
Construction Management with a focus on
water systems from Concordia University.
City of Calgary
Rebecca Dziedzic
is an assistant professor in
the Department of Building,
Civil and Environmental
Engineering at Concordia
University.
WAT E R C A N A D A . N E T
WATER C AN ADA • SEP TEMBER/OCTOBER 2024
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