North Riverside Drive in Juneau restricted to local traffic over flooding risk

North Riverside Drive near Pinedale Street is restricted to local traffic only in all directions until further notice. Through traffic is barred as Alaska 511 tracks a flooding risk tied to the Suicide Basin outburst.

The restriction took effect at 9:30 p.m. Wednesday and was last updated at 9:52 a.m. Thursday. Alaska 511 lists the corridor under two separate entries, one naming Riverside Baptist Church and the other naming Riverside Condos. Both carry the system's Natural Disaster severity classification. Neither entry describes a full closure, and neither lists an end time.

The road matters beyond the households on it. The City and Borough of Juneau has identified Riverside Drive as part of the main evacuation routing network for the Mendenhall Valley flood zone. In its flood-response notice, the city said, "Please avoid these areas and do not drive on flooded roads."

NWS Juneau's flood warning for the City and Borough of Juneau remains in effect until 4:30 a.m. Friday. The office issued the warning Tuesday afternoon and has corrected and continued it repeatedly since, most recently Thursday morning.

The warning is tied to the annual release of Suicide Basin, the ice-dammed lake above the Mendenhall Glacier. The National Weather Service reported water flowing over the ice dam on Aug. 11, and a release into Mendenhall Lake and the Mendenhall River followed. National Weather Service warning coordination meteorologist Nicole Barron said at a briefing Wednesday afternoon that the office had issued the flood warning "yesterday afternoon for an expected crest tomorrow morning between 16.1 and 16.6 feet. Rough timeline of when that crest would happen is Thursday morning between 5:00 AM and 9:00 AM." Her reference to "yesterday" places the initial warning on Tuesday afternoon, matching the issuance notice from NWS Juneau. Alaska News previously covered the Unified Command request that residents of roughly 2,000 Mendenhall Valley homes, an estimated 5,000 people, finish evacuating by 3 p.m. Wednesday.

The city opened an emergency evacuation shelter at the Floyd Dryden gymnasium and is staffing a flood information hotline around the clock through the event. City guidance asks residents to stay out of the mapped evacuation area until officials issue an all clear.