I visited the west side of the Elwha River delta. The road dead ends at a trail head at a dike with a wide gravel path along the top of the dike.
Dike trail
Dike trail with estuary pond
View west from the dike
The dike was built to block the river from cutting hard to the west and eroding the homes and former Elwha village site as well as a cemetery along the shore to the west of the delta. An 1860s map indicates that the village was there at that time. The dike was in place by 1977.
Oblique aerial view (Ecology, 1977)
The river has since shifted away from the dike so its purpose is not so obvious when walking it today.
Oblique aerial (Ecology, 2016)
The past few years there has been a very large influx of sediment post dam removal on the Elwha (https://www.usgs.gov/news/moving-mountains-elwha-river-still-changing-five-years-after-world-s-largest-dam-removal).
One of the gig changes at least in the short term is the expansion of the beach to the west of the delta. The beach has become wider and substantially less steep and has a large accumulation of wood on the uppermost part of the beach.
beach to the west
Wood on expanded upper beach
outlet of the Elwha
Broad gravel plain along river in the tidal area
I followed a trail through the riparian area of the forest to the river bank and then followed the river to the dike and returned to the trail via the dike trail. Hence, the pictures are in reverse order of my own visit.
Gravel deposits and bars at the former river ford above the delta
sediment and wood deposited within the riparian forest along river
Very high cut bank into the ice age former coastal plain
2 comments:
In the last photo showing a cut bank, is that a tephra layer several meters below the surface? Or fine sand?
Given the location it is not likely tephra, but I have not looked closely at this high cut bank. The geology map correlates the unit with Olympic sourced sediment. So I would guess fine sand or possibly a silt layer.
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