Sunnyside Flood Barrier
Project update: February 2024
March 2024: Approximately 24 trees will be removed on the south side of Memorial Drive near 14th Street and 5th Street beginning in mid-March (see map below). Trees are being removed now to align with migratory bird nesting requirements. Tree removal notices will be posted the week of Feb. 26. The 24 trees being removed are not Memorial Trees. Approximately 337 trees will be removed for the project in total, with the majority being removed in 2025.
Summer 2024: Construction is anticipated to begin summer 2024. Additional information on construction will be shared later this spring. Construction will continue into 2025.
What to expect:
Every effort will be made to limit impacts. Not all noise, dust or vibration will be able to be mitigated and we apologize in advance for any inconvenience.
Access will remain open for drivers during tree removals, however temporary staggered closures and detours along the pedestrian and bicycle paths will be in place. Please follow all posted signage to ensure pedestrian and worker safety.
About the project
We know that building a permanent flood barrier is vital to help protect people, homes, and businesses in Sunnyside and Hillhurst from river flooding. We a’re committed to delivering a 1:100 level flood barrier. This will help us manage flood water and avoid the type of damage we saw in 2013, while providing the building blocks for future climate resiliency. Additional protection may also be offered through a new Bow River reservoir.
The barrier’s location along one of Calgary’s most cherished corridors, is an important consideration. This space must be protected and where possible, enhanced. When designing and constructing the flood barrier, we have had a chance to build upon improvements to this area that have happened over the last 10 years and continue to improve the entire public space surrounding Memorial Drive from 14th Street to Centre Street while adding critical flood protection. The new flood barrier will also provide the building blocks for future climate resiliency.
Construction information session resources
The project team held an information session on Wednesday, October 4 to provide details on flood barrier design and construction.
The first phase of construction will focus on enabling work (early work that must be completed before barrier construction can start). As we work through the details with our design team and construction manager, we will share information on what enabling work will be taking place, the schedule for the work and any construction impacts the public could expect to see. During construction, we are committed to support and provide ways to move to and through the local Sunnyside/Kensington and Riley Communities that emphasize safe, accessible, and efficient movement. Please check back on our website for schedule and construction updates.
Tree inventory and Removal
Removing a tree is always a last resort. However, to make improvements in the area, some tree loss is unavoidable. Approximately 337 tree removals are required as part of the project. 24 of those trees will be removed in spring 2024 with the remainder being removed in 2025.
Many trees will be repurposed in:
- Fish compensation projects
- Habitat restoration work for fish and wildlife
- The construction of planting beds and seating around Sunnyside and around Prince’s Island
In advance of the enabling works and main construction, our team took inventory, surveyed and completed heath assessments of each tree on site. We plan to replant a total of 280 new trees in addition to new flowers and shrubs. We have also made modifications to the original design of the flood barrier to minimize required tree removals.
For more information on Memorial Drive Trees, please visit Memorial Drive trees.
Homes, buildings and other infrastructure in Sunnyside are impacted when river flows reach levels of 927 m3/s (1:10). There is a 10 per cent chance of this occurring every year. Find out if your property is at risk of flooding.
To protect Sunnyside from future flooding, the Flood Mitigation Measures Assessment (FMMA) report, approved by Council in spring of 2017, recommended that a combination of mitigation solutions that work together to create a flexible and adaptable flood risk management program. Each piece of the strategy provides great benefits independently, but together, they ensure the most effective flood protection strategy.
Below is a summary of this multi-measure approach to building flood resiliency that includes the construction of a new upstream reservoir, as well as changes to the TransAlta’s Ghost Reservoir and the construction of community-level flood barriers.
Learn more about Calgary's Flood Mitigation and Resiliency Plan.
After working with the community and completing a Triple Bottom Line evaluation to explore different options for a flood barrier in Sunnyside, Council approved the 1 in 100-year flood barrier height that will help protect people, homes and businesses in Sunnyside/Hillhurst from river flooding.
Benefits of the 1 in 100-year flood level barrier height
- Reduces the 2013-level flood risk, which will be further reduced by current and future upstream reservoirs on the Bow River.
- Less disruptive to the community look and feel
- Increases the ability to protect vulnerable populations
- Meets the provincial and federal flood standard (1 in 100-year)
- Provides the building blocks for future climate resiliency
Due in part to the geography as well as an outdated drainage system, Sunnyside is more prone to flooding and this is something that The City is working to fix. In addition to the flood barrier, several projects have been completed or are currently underway to reduce flooding that happens in the community.
Visit Calgary.ca/sunnysidecdi for a list of projects and up to date information.
The location of the flood wall is not yet finalized; the location will be refined as the design progresses. The general alignment of the flood barrier has been determined. We are currently in the detailed design stage, which takes a closer look at the constraints and refines the design such as the exact location and type of flood barrier over the 1.9 km length.
The 1 in 100-year option is the recommended barrier height for Sunnyside because it’s reflective of the best balance between social, environmental and economic considerations. It’s an investment that enhances the safety of residents and our ability to protect those most vulnerable, while having a lesser impact to the community look and feel. The 1 in 100-year option meets the federal and provincial flood protection standards. When constructed, it will immediately reduce Sunnyside’s risk from a 2013-level flood. This option will be further enhanced by current and future upstream reservoirs on the Bow River, allowing it to manage even larger floods.
Feedback garnered through public engagement will be used to inform elements such as public amenities and open space adjacent to the flood barrier and will not inform any design decisions for the flood barrier. We do not anticipate that engagement for the Memorial Parkway project will delay the overall construction timelines for the Sunnyside Flood Barrier project.
As we advanced the flood barrier design, we recognized the significant impact this project would have on the area. During this time, it also uncovered some opportunities to integrate the flood barrier into other work that was happening in this area and a desire to capitalize on this moment to protect and enhance the area as much as possible while adding the flood protection.
To help increase flood resiliency and create spaces that enhance the connection with the river, natural environment and commemorate our heritage, we’re combining this work through an integrated program. We recognized that by taking a more integrated approach we could achieve the best outcome for the area.
As part of The City’s emergency response plan, we are ready to respond, if needed, in areas that are still vulnerable to river flooding. We stockpile riverbank protection and temporary barrier materials and each spring our City teams review their plans, conduct site visits and train crews.
In addition, every spring, infrastructure such as water main valves, stormwater outfall gates, lift stations and pump are prepared, tested or positioned for flood season to reduce potential damages during a flood.
PCL Construction Management Inc. (PCL) has been selected as the construction manager for delivery of the Sunnyside Flood Barrier project and public realm improvements.
We are using a construction management approach to allow the project team greater design flexibility and project control to address schedule and community impacts.
We know that there are several historical and socially significant sections of the Sunnyside Flood Barrier alignment, so using a construction management approach allows more time to work through the details of those while getting started on the more straightforward areas.
Related documents and links
- Memorial Parkway Program
- Previous engagement on the Sunnyside flood barrier
- Community Flood Barriers - studies and reports
- River flooding in Calgary
- Calgary’s Flood Resilience Plan
- Flood-related glossary of terms
- Calgary’s Environment Strategy
- June 2023 newsletter
- Oct 2023 session information boards
Oct 2023 session east alignment drawings
- Oct 2023 session west alignment drawings