Revised provincial flood maps for the Bow and Elbow Rivers show a dramatic decrease in potential impacts, and the new data comes at an ideal time, one Calgary councillor said.

With the Springbank Off-Stream Reservoir now online, and tens of millions in added flood mitigation infrastructure in place or in progress, the impact of a 1-in-100-year flood on the Elbow River is nearly eliminated, according to the maps.

Further, mitigation along the Bow River has significantly reduced the potential impact of flood damage along that waterway.

“We committed to protect Calgary and other communities from floods and we are seeing the results,” said Rebecca Schulz, Minister of Environment and Protected Areas, in a prepared provincial news release. 

“These new flood maps are good news for families and businesses, but we are also going to keep investing in reservoirs, berms, updated flood maps and the critical infrastructure needed to keep people and their property safe.”

While the province has expedited the update of flood maps across Alberta, it has been many years and a massive 2013 flood since new mapping was made available.

In 2013, a massive flood tore through Calgary and southern Alberta, prompting hundreds of millions in spending on flood mitigation to reduce the risk. The City of Calgary now says that along the Elbow River, Calgary’s flood risk has been reduced by 70 per cent.

The province is currently working on the Ghost Dam relocation project, which will expand the storage capacity upstream on the Bow River, thus providing additional flood protection to Calgary. That project, however, is tentatively on the books for more than a decade down the road.

Maps help with awareness on development

The City of Calgary said that the new maps are important, as their understanding of the rivers has grown since 2013, and their potential impact to communities.

“It’s critical, while facing housing and affordability concerns, that the best, up-to-date flood hazard information is available, so we can keep building an informed, flood-resilient Calgary,” said Frank Frigo, manager of environmental management with the City of Calgary.

Ward 1 Coun. Sonya Sharp said that the map release was timely as the Bowness flood mitigation group was set to have their annual general meeting.

“I think that once we see where the maps are and for future development, that will also help the residents in Bowness and Montgomery understand where we’re going with some of the flood mitigation process and working along with the province,” Sharp told reporters on Tuesday.

Plans for a Bowness Flood Barrier were in progress until 2021. A feasibility study at the time showed that a barrier would be effective in reducing basement and main floor damage from overland flooding, according to the City of Calgary’s project webpage.

Residents in the area wanted more information on the province’s upstream mitigation plans before further work on the Bowness flood barrier. As a result, no further work has been done.

Sharp said that a big problem in the area is groundwater seepage. Seeing the maps might help with a better understanding of the potential flood issues, she said.

“I know people got a little bit concerned about the water issue last year, even though it was a pipe failure, we talk about water seepage,” she said.

“So, every time there’s a water main break in some of these communities, like Bowness, it’s generally the water that’s coming from the ground up.”

You can view the province’s new flood maps for Calgary here.