Flood — Upper Koyukuk Valley, Alaska

2023-06-10 to 2023-06-13 · near Allakaket, Upper Koyukuk Valley, Alaska

Event narrative

Water levels on the Koyukuk River at Allakaket rose overbank in low-lying areas of the community near the river on June 10th. Minor flooding was reported when the water crested early Monday morning June 12th. Water inundated the old runway by the river and overtopped Stanley Slough Road near the boat launch. A local observer reported that the high water and debris was initially coming from the Alatna River on June 10th but then coming down the Koyukuk River by June 11th. It is estimated water levels would need to rise approximately 1 additional foot to go over roads in the lower part of the village and have more significant impacts.

Wider weather episode

A weather front brought high freezing levels and heavy rain to the Brooks Range. The combination of rainfall and snowmelt runoff from a late winter snowpack resulted in minor flooding along the Koyukuk River and tributaries draining the Brooks Range. Rainfall totals ranged from 1 to 2 inches between June 8th to the 10th, with the bulk of the rain falling in less than 24 hours.

View location on OpenStreetMap → (66.5706, -152.6315)

Source: NOAA Storm Events Database, event_id 1120060. Narrative written by the NWS forecast office that issued the report.