Flood in Susitna Valley, Alaska

The flood gauge near Talkeetna at the confluence of the Talkeetna River and Susitna River rose into flood stage around 12 PM AKST August 29th, crested just below major flood stage at 14.93 ft around 11 PM AKST August 29th, then receded back to below minor flood stage by 12 PM AKST August 30th. This was the third highest crest on record for the gauge, and highest water level recorded since 2012. Pictures from Talkeetna by an NWS employee on 8/30 showed overbank flooding at the end of Main Street. Low lying areas of Talkeetna, particularly the lower west side of town, experienced flood waters from high water on the Susitna. Worst impacts were to the Alaska Dream Cabins that are located at the west end of Main Street / B Street and by the water. The Alaska River Forecast Center found high water marks of 1-2 ft on several buildings. Despite some raising of buildings, Water reached the lowest few inches to foot of many of the buildings. The Talkeetna River Park and campground experienced flooding as well as the low-lying areas between the campground and revetment.

An atmospheric river moved up from the North Pacific into Southcentral Alaska and produced widespread moderate rainfall between August 27th and August 29th. Strong southerly flow during the rainfall event caused south-facing slopes of the mountains across Southcentral to get the highest rainfall totals due to enhancement from upslope flow, including the north end of the Susitna Valley, where 2.5 to locally 6 inches of rainfall was recorded between 8/27 and 8/29. The runoff from the heavy rainfall pushed multiple waterways across the Susitna Valley into moderate flood stage from around 8/29 to 8/31, including sections of the Talkeetna River, Yentna River and Moose Creek.