A provincial government report says the expansive network of dikes across the Lower Mainland will need major upgrades over the next several decades to fend off the rising sea.
The cost of the improvements could amount to up to $9.5 billion, the report says, but that's over the next 100 years.
The report studied the dikes along the Metro Vancouver coast and the Fraser River downstream of the Port Mann Bridge.
The area encompasses 250 kilometres of shoreline, 12 major municipalities and over two million people.
The report was released from the Ministry of Forests, Lands and Natural Resource Operations and is meant to get communities thinking about upgrade plans now.
It's a follow up to a 2011 report that predicted sea levels will rise by one metre along BC's coast by the turn of the next century.