Wednesday, March 12, 2008
I arrived near this same spot last June, from the other direction. The shoreline that extends northwest from the mouth of the Nisqually crosses a series of small drainages. They originally formed when sea level was lower and have subsequently been flooded, resulting in a series of drowned valley estuaries. Spits have formed across most of their mouths, creating what I call barrier estuaries, but which belong to a more general class of features on Puget Sound most of us call "pocket estuaries." The name fits.
There are lots of these in southern Puget Sound. The sea level history is more conducive to them here than farther north. It rains more down here, so the drainage networks are more developed. And there has been less wave erosion to smooth out the coast and remove little divots like these. There are intertidal deltas at the mouths of each of these that are part stream delta, part ebb-tide delta. I suspect much of the wood scattered across the beach was flushed out during the December storm.