City going ahead with 4 new flood barriers on Bow River
Work will proceed while upstream mitigation remains uncertain
As flood season approaches, the city is moving ahead with plans for four new community flood barriers to protect vulnerable areas along the Bow River.
Many Calgary river communities were damaged by a devastating flood in 2013.
While the provincial government's money and commitment are needed to complete upstream mitigation projects on the Bow and Elbow rivers, the city is continuing to reinforce riverbanks.
Construction may start later this year on a new flood barrier along the south bank of the Bow River between the Jaipur bridge and the Reconciliation bridge.
Design work is continuing on three others which will protect Hillhurst-Sunnyside, Bowness and Pearce Estate park.
Each barrier is different
The leader of watershed analysis with the city's water resources division, Frank Frigo, said there are a number of steps each project must go through before construction can start.
That means they cannot be built all at the same time.
"Many of those are technical and recognizing both the funding and delivery realities associated with each project, we have taken a prioritized approach to implementing each of the projects," said Frigo.
Each one has its own peculiarities.
He said the Bowness barrier is somewhat unique, so city officials have literally been going door to door in recent months to meet with affected property owners.
"Much of the flood barrier that has been conceptualized and is being looked at together with the community in order to be effective must be situated at least partly on private land," said Frigo.
When completed, the barriers will provide protection to surrounding areas against a 1-in-200 year flood event.
But they would not negate the need for a major new dam or storage reservoir upstream on the Bow to protect Calgary against future floods.
Elbow river also needs upstream mitigation
On the Elbow river, it's a different story.
Work on new gates for the Glenmore dam is expected to be completed later this year, adding to the storage capacity of the reservoir.
The province has been acquiring land in the Springbank area to clear the way for the construction of an off-stream diversion reservoir.
When combined with the Glenmore improvements, that would help prevent flooding on the Elbow in Calgary.
Frigo said long-term meteorological forecasts are calling for above-average precipitation in the May-June-July period.
Current ground moisture and snowpack levels are relatively low.
However he points out that conditions can change quickly.
Once again this year, water levels on upstream reservoirs are being managed to ensure there is available storage capacity, should there be a repeat of the conditions that caused the 2013 flood.