Landslides Along Nushagak River

Observation by Constantine Johnson:

We spend a lot of time along the river during moose season and one day on our way home a new landslide was present. I'm sure the landslide occurred from all the rain we had this summer and fall. There are landslides along that bank but they have been there for years. The landslides in the pictures below are new. These pictures are 5 different places along the river bank, same bank just not so far from each other.

LEO Says:

We are seeing major and minor landslides all around Alaska this past summer and fall. A similar landslide up on the Alatna river was documented in August (see video in Alatna observation in sidebar). Both areas have seen a unusual amount of rain. Major landslides such as the ones in Southeast Alaska are dramatic and a big concern due to safety for the communities. How do these small landslides impact a community? Some potential impacts may include disturbance of fish habitat and spawning grounds, high and muddy water during moose season, navigation concerns related to grounded debris or trees floating down river, more turbid conditions for drinking water treatement, and safety and infrastructure impacts if landslide occurs in community.

As you can see in the graph below much of Alaska has seen above normal rainfalls in the month of August and local rain totals in the area are summarized by Rick Thoman.

Consult by Rick Thoman:

July 1 to late September: NOAA climate reference network station near Aleknagik has reported over 16 inches of rain and the NWS automated station at Iliamna has reported about 15 inches of rain. These amounts are roughly 1.5 to 2.5 times normal.