Metro Vancouver has issued an evacuation alert for Barnston Island as water levels rise in the Fraser River.

The regional district is advising residents to be prepared to leave the island quickly in the event of flooding.

The evacuation alert took effect at 8 a.m. today (June 21) and will stay in place until further notice.

"This is an alert about potential danger only," a Metro news release states. "Barnston Island residents are not required to evacuate at this time."

Metro says its staff is monitoring river levels and patrolling dikes around the island, and sandbags are being put in place.

Starting at noon, access to Barnston Island will be restricted to residents and businesses, and people having a business or family reason for going to the island.

According to Metro, children and minors must leave the island if there is an evacuation order.

The B.C. River Forecast Centre has a high streamflow advisory in effect for the lower Fraser River.

"The Fraser River at Mission (08MH024) is currently forecasted to reach 6.38 m late on Thursday, and due to tidal influences the river is expected continue to rise through the weekend, with daily peak levels of up to 6.75 m," the centre stated in an update issued on Wednesday (June 20) at  5 p.m.

Barnston Island lies west of the Golden Ears Bridge in Electoral Area A and had a population of 137 in 2011.

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