Purpose:
Too much of a good thing may still be a good thing, but too much sediment in water can be a pollutant. In fact, California's Clean Water Act lists Sonoma Creek as impaired by sediment. The concern about sediment-such as silt, clay, and sand-in stream water stems from its potentially adverse effects to habitat for threatened native species such as steelhead and salmon.

During wet storms, heavy runoff carries sediment to tributaries and creeks. Increased suspended sediment (sediment carried by water) can elevate turbidity (water clarity), which negatively impacts fish. Highly turbid waters have been observed to promote physiological stress, reduce growth rates, and impair the ability of species to feed. Damage by sediment to gills can cause outright fatalities. Given the right conditions, stream sediment also clogs spawning gravels, limiting reproductive success.

The Sonoma Ecology Center, a nonprofit group working toward a condition of sustainable ecological health in the Sonoma Valley, is monitoring turbidity and suspended sediment exposures for aquatic organisms in mainstem Sonoma Creek and selected tributaries.

Contact for the Project:
Rebecca Lawton (Geologist)
Phone: (707) 996-0712
Email: sec-lawton@vom.com