As the largest river by volume flowing from the Americas into the Pacific Ocean, the Columbia transports an estimated 5 million tons of sediment downstream toward its mouth each year. The river also moves large amounts of sediment eroded from the landscape, depositing it into the vast river system. The Columbia-Snake River System is a conduit for commerce, carrying millions of tons of international trade by large container vessels each year. Sandy coastlines are a valuable resource that protect human-made structures from waves, serve as habitat for important species, and provide a variety of recreational opportunities. The USGS uses a variety of survey tools-including jet skis equipped with GPS and sonar-to measure how sandy coastlines change over time. Sources/Usage: Some content may have restrictions.
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