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Flood — Juneau Borough, AK

Jul 19, 2018

Throughout spring and the first part of the summer Suicide Basin, a side valley that is dammed by the Mendenhall Glacier, filled with water from snow melt and rainfall. In the afternoon hours of July 17th visual reports showed signs of the basin beginning to drain as the glacier dam was starting to fail. The river gauge in the Mendenhall Lake started to show this inflow of water from the basin through the evening hours and by the morning of the 18th the event was well on its way. For the next 2

Source: NOAA National Weather Service Storm Events Database (event 774303). Narrative written by NWS staff at the time of the event.

Flood Risk Context for Juneau Borough, AK

This event is one of many recorded floods in Juneau Borough County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.

View Juneau Borough County flood data →

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