Since 2013 the City has undertaken many technical studies as well as a lot of
community engagement to really help define what Calgary's flood mitigation
strategy is all about
Through the engagement through the technical studies
we found that a multi prong approach around flood mitigation is really the
best solution one mitigation strategy is not going to do it
so we've taken a multi-pronged approach
which includes upstream reservoirs on the Bow and
the Elbow River it includes managing the existing reservoirs such as
a Ghost reservoir and Glenmore reservoir more effectively it involves building
community barriers in some of the high-risk communities as well as
citizens taking responsibility through property level mitigation
So a reservoir really analogous to a bathtub and really it's a large pot or basin which is
storing water and then releasing it just like the drain in a bathtub so if we can
size if you will the drain on the bathtub
and build the bathtub large enough to maintain the appropriate flows then we
can avoid avoid damage on the Bow there are about eight power structures they're
all owned by TransAlta corporation so the City of Calgary doesn't own or
operate any significant infrastructure on the Bow river upstream but we do work
very closely with partners like Alberta Environment and TransAlta to ensure
adequate operation reasonable operation of those of those structures
So to better control the flow of water on the Elbow River the City is undertaking
improvements to the Glenmore dam and this is going to increase the gates
the gates size on the Glenmore dam which will allow more water storage and will
allow better management during flood for the Elbow River
The City is very supportive of
province of Alberta's five year agreement with TransAlta utilities
to manage the Ghost reservoir for flood
It's important that the barriers are built now because the studies the
construction the design of the upstream reservoirs could take years and even
decades so in order to protect the communities for more frequent smaller
events it's really critical to have them in place by building the barriers first
the risk of damages to the communities will decrease significantly and in
conjunction with the upstream reservoirs it will only enhance the flood
protection for the communities
Temporary flood barriers are something that
the City can use but one of the key strikes against the you know efficiency or
effectiveness of temporary barriers on long long reaches is the fact that we do
have very short response times from the time it rains to the time that floods
reach our jurisdiction here in Calgary is really in a matter of hours and so it
does become very difficult to put in place the kinds of nor that height the
type form of structure that would actually work so unfortunately we're not
a jurisdiction like Winnipeg for instance where the flood mechanism
occurs due to Plains snowmelt and that process is slow it happens over several
weeks to a month so that process is relatively predictable and there's lots
of time to be able to respond with only hours to respond it becomes difficult to
put in place the kind of infrastructure we know could be stable the amount of
investment and even to do that you know even if you're contemplating in
temporary barriers year by year the overall length the height the amount of
disruption to our communities would generally not be rewarded or analysis
show pretty clearly that that kind of option on its own isn't enough
Once the flood mitigation plan is in place and the barriers and upstream mitigation are
working together the city and the communities will be protected to more
frequent and intense events which we are anticipating in the future