Sediment

Agriculture, development, stormwater, logging, dams, and other land-based activities send sediment-laden runoff into California's water bodies. When sediment settles to the bottom of a stream, river, lake, estuary, or bay, it can smother important habitats such as salmon-spawning grounds or underwater vegetation, with potentially devastating impacts. Salmon populations rely on clean, gravelly streambeds for nesting. As sediment overwhelms streambeds, the small, oxygen-rich pools necessary for rearing young salmon are eliminated. Sediment in the water also makes it hard for fish to see and clogs their gills. In addition to impacts on salmon populations and associated fishing activities, high sediment levels can jeopardize harbors and shipping channels, posing economic impacts there as well.

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