Richmond to continue investment in flood protection

16 December 2021

Although the City of Richmond fared well during the recent extreme weather events, the City will continue to invest resources to strengthen and upgrade its flood protection infrastructure to protect residents against the future extreme weather that is expected to occur due to climate change.

Three Atmospheric Rivers hit the region between November 13 and 30, including one event that resulted in over 130 millimetres of rain falling on Richmond over three days. While it did not experience the same level of rainfall or flooding issues as some areas of the Fraser Valley, Richmond did require extensive use of the City’s 39 drainage pump stations and staff to keep things secure.

“The City has invested over $120 million in our dikes and flood protection infrastructure,” said Mayor Malcolm Brodie. “Such investment is crucial to protect the community from the risks of weather events as well as rising sea levels attributed to climate change. Recent events only reinforce the value of that commitment and the need for more.”

At the peak of the November storms, each of the City’s 39 pump stations were moving water at or near full capacity at some point during the event. The capacity of these pump stations has been increased 29 percent since 2005, and they now have a combined discharge rate of approximately 90 cubic metres per second (1.4 million US gallons per minute) – the equivalent of over two Olympic swimming pools every 60 seconds.

Richmond’s 49 kilometres of dikes held back water from the Fraser River, and City crews worked 24/7 to keep the 165 kilometres of watercourses, 61 kilometres of box culverts and 585 kilometres of drainage pipes clear of debris and functional.

Some parks, which are purposefully designed as storm overflow reservoirs, temporarily flooded with several centimetres of rain water until it drained through watercourses. Other low-lying areas experienced pooling water and localized flooding due to ground saturation, and residents who sought additional protection collected over 500 sandbags from the City Works Yard.

Richmond’s current multi-faceted infrastructure is the result of the City’s Flood Protection Management Strategy and Dike Master Plan that guide continual upgrades and improvements to address climate change-induced sea level rise. The City closely monitors evolving climate change data and adjusts plans accordingly.

Current climate change science estimates that sea levels will rise approximately one metre by the year 2100, while land in Richmond is projected to subside by 0.2 metres over the same time span.

To provide additional resilience for Richmond’s population against this flood risk, the City is accelerating the dike upgrade program over the next 50 years to raise dikes well in advance of current sea level rise projections. The existing dike network can withstand high water events such as spring freshet and king tides and handle a 500-year return period (estimated average time between) flooding event.

Over the past 20 years, the average intensity of rainfall events in Richmond has increased by approximately 15 per cent. This is consistent with predicted climate change impacts on local weather patterns and reinforces the need for the City’s continued flood protection program.

Council recently supported the need for more investment in the existing flood protection infrastructure despite its performance in managing one of the heaviest rainfall months on record. It asked staff to look at what might be required to implement dike upgrades sooner than the planned timeline, and to identify what other investments might be valuable.

The City will also undertake an extensive engagement with Richmond residents and property owners on Phase 4 of the Dike Master Plan in 2022 (north dike between No. 6 Road and Boundary Road). Residents will be able to learn about the City’s ongoing flood mitigation implementation plans, and provide valuable feedback and ideas on those plans.

To learn more about Richmond’s flood protection and dike master plans, and to watch two newly posted videos, visit www.richmond.ca/floodprotection.