The Elwha River delta in Washington State has prograded rapidly in the 2+ years after the removal of two dams and the rapid release of >7x106 m3 of sediment. The deposits forming new intertidal habitat near the river mouth have been characterized as sandy, but observed grain-size variability motivated a more rigorous investigation of their sedimentology. Surficial sediment and dry bulk density samples were collected and sediment patterns analyzed relative to the topographic evolution of intertidal deposits since the initiation of dam removal. Stratigraphic patterns were investigated using 11 cores and trenches along a crossshore transect across the delta, (maximum sampled depth limited to ～1.5 meters). Surficial grain sizes ranged from mud to gravel, with the grain sizes of surface sedimentary units corresponding to the observed bar/trough morphology. In general, cores/trenches suggest that a surface layer of mud observed in troughs between bars are relatively thin (<10cm), and underlying layers are generally dominated by sand.
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