More frequent floods could threaten 300,000 peopleâ€™s homes and $50 billion worth of property, according to a report on future threats to the Fraser River.
The report by the regionâ€™s chambers of commerce identifies a host of issues that could hit B.C.â€™s most important river over the coming decades.
The population of the floodplain area, which includes parts of northern Langley and its neighbours, are dependent on 600 km of dikes, 400 flood boxes, and 100 pump stations, said the report.
If a record-setting flood reoccured along the river, it could cause tens of billions of dollars worth of damages immediately. Damaged road and rail lines and energy conduits could impact exports and imports for even longer.
â€œScientists predict that there is a one-in-three chance that a flood of similar magnitude to the record floods along the Lower Fraser will occur within the next 50 years,â€ the report said.
The record floods hit in 1894 and 1948, and both floods turn the village of Fort Langley into an island surrounded by water. During those floods, the Lower Mainland was relatively sparsely populated and had relatively few paved roads. A flood of that amount today that overtopped dikes would affect many more people.
The report calls for major protective improvements to avoid the cost of flood damages.
Rising sea levels caused by climate change could make the situation worse.
The report says 100-year flood events on the Fraser could now occur as often as every four to 10 years.
â€œClimate change will increase the risk of flooding in both the Fraser Valley and the tidal portions of the river,â€ said the report. The river is tidal as far inland as Langley.
The cost of upgrading flood defenses and dredging along the Lower Fraser River is estimated at $9.5 billion. Of that, $8.8 billion would impact the tidal parts of the Lower Fraser below the Port Mann Bridge.
The report also says not enough is being done to dredge sediment that accumulates in the Lower Fraser every year.
â€œThis report found that Fraser River communities such as Langley would face catastrophic impacts in the event of flooding,â€ said Greater Langley Chamber of Commerce president Kristine Simpson. â€œThis report paints a very clear picture that, with risks of this magnitude, our communities need to partner with government and major stakeholders to find solutions now.â€
â€œThe Lower Fraser River has significant economic importance to the entire lower mainland region,â€ said Simpson. â€œThat includes jobs, economic activity, and tax revenue to local, provincial and federal governments. Our very existence as a community would be threatened if those are impacted.â€
Lower Mainland chambers of commerce will host a forum on the risks to the Lower Fraser River this fall in Surrey, meeting with various government and First Nations representatives.