001-43_EJQR9_SUMMER26_PT - Flipbook - Page 24
And then understand how what we’re doing on the surface improves our
pipe system.”
Vancouver has been working on reducing CSOs for decades, having
successfully removed about 445 km of combined sewer mains. But an
estimated 44 per cent of combined sewer network remains to be separated
within the relatively short timeframe of 2050—the city’s proverbial line in
the sand for eliminating CSOs altogether.
As Steward readily admits “there are parts of the city that aren’t going to be
separated for quite a long time just because there’s so much work to do. But
by putting nature-based solutions or green rain infrastructure into some of
these catchments it helps us to mitigate some of the 昀氀ooding.”
In an e昀昀ort to o昀昀set the likelihood of increased 昀氀ooding due to
Vancouver’s ongoing residential development, the city has also
introduced a Sewer and Watercourse By-Law which Steward says limits
the rainwater discharge at a maximum of 25 liters per second per hectare
for certain storm events. So (new developments) can do that with naturebased solutions on their site (or) they could do it with a detention tank on
their site.”
Airing on the side of less pollution
As cities continue to deal with decades of density done not so well, Josipa Petrunic,
founder of the Canadian Urban Transit Research and Innovation Consortium
(CUTRIC) observes that “the starting point to decarbonize a city (for municipalities)
is you have to decarbonize transit,” which she says represents the “lion’s share” of
airborne pollution tied to city operations.
While that source of pollution is small compared to emissions generated by personal
vehicles and trucks in an urban setting, diesel buses used for public transit or for school
buses disproportionately pollute the air at street level, contributing high levels of CO2,
nitrogen oxide emissions pose a direct health threat to commuters, people living in
transit corridors and both students and those living in school neighbourhoods.
CUTRIC seeks to o昀昀set such challenges by helping cities to transition to
zero emission transit systems, producing everything from feasibility to
implementation plans.
Petrunic credits the Zero Emission Transit Fund, which is slated to allocate over $2
billion over four years towards the purchase of 5,000 zero emission buses as a game
changer for public transit in this country.
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