Alaska 511 flags flooding risk on Back Loop Bridge Trailhead road in Juneau

Alaska 511 reported a flooding risk Wednesday at 8:30 p.m. AKDT at mile marker 4 on Back Loop Bridge Trailhead Forest Service Road, in both directions. The road is not fully closed. Lane data is unavailable, and no end time is posted. Drivers should use caution because conditions may be hazardous.

Alaska 511 classifies the event under its natural disaster severity level. The site sits on the west side of the Mendenhall Valley, near the trailhead the U.S. Forest Service closed in June for flood wall construction.

The notice comes amid Juneau's response to glacial outburst flooding. Alaska News previously reported that nearly 1,900 homes sit inside the borough's local flood advisory area. The borough has posted emergency guidance routing some west-side traffic onto Mendenhall Loop Road while telling motorists to avoid Back Loop Bridge. "If you are in a flood zone, evacuation is advised," the city's flood response page says. The borough is running a flood information hotline at (907) 500-0890.

The Forest Service said in a June 11 release that a new earthen berm near Back Loop Road would "provide flood protection for Back Loop Road and downstream portions of the community."