Flood — Middle Tanana Valley, Alaska

2014-06-20 to 2014-06-21 · near Eielson Afb, Middle Tanana Valley, Alaska

Event narrative

This event is for the Salcha River flooding.

Wider weather episode

A weather system moved in from the Upper Tanana Valley on the 18th and stalled over the area through the 20th, dropping two to five inches of rain across the basins of the Chena, Salcha, and Goodpaster Rivers on the 18th through 20th.

Chena River Basin: Two to three inches of rain fell over the Upper Chena River Basin on the 19th through 21st. The Upper Chena gauge at Mile 40 Chena Hot Springs Rd recorded a crest of 21.86 feet around 0700AKST Fri the 20th. This is the highest observed crest since July 2003 and ranks as the 6th highest crest at the Upper Chena gauge. The Hunts Fork gauge crested at 18.9 feet around 03:00 ADT Sat the 21st. Impacts due to the flood were observed in the Chena Recreation Area and at some private residences in the Two Rivers area east of Fairbanks. From 1 to 2 feet of water flowed over Chena Hot Springs Rd at Milepost 36.9. The road was impassable to most vehicles on Friday June 20th and people east of the flooded area were unable to get back to town until the floodwater receded. Flooding was noted at the parking lot at Granite Tors, the Stiles Creek shooting range, and much of the low lying areas along Chena Hot Springs Rd in the Recreation area. There was minor flooding and erosion at the Rosehip Campground. The Steve Savage Trail in Two River near 25 mile Chena Hot Springs Rd was impassible with water waist deep in some areas. A resident reported many driveways partially flooded but no houses. The U.S. Army Corps of Engineers operated the Moose Creek Dam from 0400AKST on Sat June 21st to 0100AKST Monday June 23rd in order to regulate the flow of the Chena River through the dam to 8,000 cubic feet per second. This is the first time the flow of the Chena River has been regulated since July 2008. Water was impounded by the dam and a large pool developed.

Goldstream Creek: Around 3 inches of rain fell in the Goldstream Creek basin just north of Fairbanks, and resulted in the washout of a one lane bridge to a private residence. Estimated damage is $5000.

Salcha River Basin: Three to five inches of rain fell over the Salcha Basin from the 18th through the 20th. The Salcha River gage at the Richardson Highway recorded a crest of 18.34 feet at 2200AKST Fri the 20th, which is the highest observed crest since August 1986 (stage 18.67 ft) and ranks as the 3rd highest rainfall driven crest on the Salcha River. The Salcha River is densely populated with recreational cabins and some permanent residents. A NWS Coop observer reported 3-4 feet of water in their yard. Their main buildings are elevated and barely remained dry. Outbuildings and other structures received damage and were lifted and moved throughout the yard, including a greenhouse, deck, hot tub, and wood pile. The observer also reported seeing a hot tub floating downriver. The coop observer lives on a higher bank. Many cabins received significant damage and severe bank erosion. The boat launch parking area at the Richardson Highway bridge was inundated with at least 1 to 3 feet of flowing water, the outhouses were flooded, and the dumpsters were carried down river. Roads to private residences adjacent to the river near the Richardson Highway bridge were inundated and impassable and several homes were surrounded by water and likely flooded. The sediment around the abutment on the Clear Creek bridge at mile 324 Richardson Highway about mile northeast of the Salcha River was eroded and 3-6 foot hole opened up in the highway. The highway was closed the evening of the 21st through the morning of the 22nd. Clear Creek was very high and carrying Salcha River water. Damage amounts are guesses on the costs to repair various cabins.

Goodpaster River Basin: Two to nearly five inches of rain fell during the 18th through 19th. The Goodpaster RAWS reported the highest rainfall with 4.61 inches. The Pogo Mine received 2.62 inches. Approximately 1/3 of the Pogo Mine airstrip was inundated with water but still usable, and there was minor flooding of lower Pogo Mine camp warehouse yard and some roads adjacent to the river. the stage crested at 20.1 ft near the Pogo Mine, or 0.6 feet above flood stage. Downstream the flooding was more severe, as most all residents received impact from the high water. There were many cabins that got wet, most of them on the upper portion of the river, below the forks. Damage amounts are guesses as to the coasts for cabins and road repairs.

View location on OpenStreetMap → (64.5793, -145.9644)

Source: NOAA Storm Events Database, event_id 534599. Narrative written by the NWS forecast office that issued the report.