Coquitlam looks to kickstart flood mitigation work in 2027

The city’s most vulnerable spot might be the confluence of the Fraser and Coquitlam rivers.

The area has flooded 21 times since 1909, according to the Kwikwetlem First Nation. A major flood would cost an estimated $370 million solely based on damage to Mayfair Industrial Park, according to a 2018 estimate.

After getting a $16.3 million grant from senior levels of government, Coquitlam city staff are working on a flood mitigation plan with four years of construction tentatively slated to begin in 2027.

Having cities take responsibility for staving off flooding is backwards, according to Coun. Dennis Marsden, who called the approach “fraught with peril.”

“The management of flooding cannot be done on a regional or municipal-by-municipal basis,” he said Monday. “It can just become a political football.”

One city’s work could be undercut by a municipal neighbour neglecting their stretch of the waterway, Marsden said, adding that the issue of flood mitigation would be better handled by the province.

The city should send a message to the provincial government, Marsden added: “You best be prepared to write bigger cheques going forward because we do not have the wherewithal to do it on our own.”

Some of the dikes through Ẳéxətəm (tla-hut-um) Regional Park, formerly Colony Farm, date back to the 1920s, according to a city staff report, which noted: “substandard dike elevations.”

The area around ƛ̓éxətəm and the Mayfair Industrial Park near United Boulevard are at particular risk of flooding, according to a 2017 assessment.

A worst-case scenario would be heavy rainfall coinciding with snowmelt swelling the Fraser River, according to a city staff report.

While there are linear dikes along the Coquitlam and Fraser rivers, as well as flood boxes and the Port Mann Pump Station, ƛ̓éxətəm isn’t protected by a dike and would face: “significant access and egress challenges in a flood,” according to a previous request for proposals from the city.

The dikes in Xéxətəm and Maquabeak Park will need to be raised, based on the city’s climate change models.

However, that long-term flood mitigation plan would likely cost between $45 and $50 million. As that exceeds the $16-million grant, the city has capped the current budget at $19.9 million.

More than 100 Tri-Cities residents reported property damage in 2024 after a three-day rainstorm pelted the region. In one 24-hour stretch of the storm Coquitlam recorded 254-millilitres of rain.

Coquitlam was hit hard by the flood, partially due to the approximately 300 kilometres of creeks that wind through the city.

In dealing with multiple washouts, down trees, and a sewer overflow, the city spent $549,317 dealing with the atmospheric river.

Coquitlam has often exceeded its extreme weather operating budget in recent years, including a more than $1 million overrun in 2022.