The Highway 9 corridor from Sedro-Wooley to Kendal follows the Samish River Valley and then after crossing a very subtle divide follows the South Fork Nooksack River Valley. I previously noted the alluvial fans associated with steams that flow into the Sanish River Valley (alluvial-fans-altering-samish-river).
Doing some review of the valley I came across this 1950 aerial of Jackson Creek with a recent debris flow scar path and deposit on the alluvial fan that extends out onto the Samish Valley floor.
Timber harvests have started up again in the Jackson Creek watershed, but the creek and the steep slopes near the creek have been partially buffered versus the previous log everything approach. The other substantive change is road construction across stream subject to debris flows have generally improved to reduce the risk of the road causing a debris flow. That said the creek is lined with steep unstable slopes and future slope failures and accumulation of debris
The Jackson Creek alluvial fan has resulted in a lake upstream from the fan and there is a lake down stream that is influenced by another alluvial fan at Mill Creek. Both of these lakes may also be influenced by beaver activity. Mill Creek had a debris flow in 1983 that resulted in a fatality.
