Study examines how to alter sediment dredging in wetlands to offset rising sea levels

SCCWRP and the University of California, Irvine have completed a four-year study exploring how altering sediment dredging practices in coastal wetlands vulnerable to sea level rise could reduce anticipated ecological impacts to plant and animal communities.

The coastal resiliency study, completed in December, found that the habitats of species like the endangered Ridgway’s rail are expected to be inundated by rising sea levels by the late 21st century, but that reduced sediment dredging in areas like upper Newport Bay in Orange County could partially offset the projected ecosystem impacts.

Dredging is a routine management practice in some estuaries that is intended to protect wetland habitats from being buried by sediment that has washed off the land, and to keep navigation channels clear.

As part of the project, researchers developed regional curves to help environmental managers more readily evaluate tradeoffs associated with various dredging frequencies and intensities in coastal wetland areas under multiple sea level rise scenarios.