Jul 7, 2024
Landscape Language
Alluvium (noun) – loose silt or sand deposited by running water in a stream bed
Due to Mount Rainier’s glaciers, rivers in the park tend to have rocky riverbeds, but you may also see alluvium. Alluvium is a general term for deposits of silt, sand, clay or other material in running water, like these ripples of sediment pictured here under the exceptionally clear waters of the Ohanapecosh River. Alluvium is more likely to be deposited after flood events when rivers can carry larger loads of sediment. In addition to creating interesting patterns, alluvium helps build up mineral-rich soil along rivers.
NPS Photo of alluvium ripples in the Ohanapecosh River. ~kl
