By Ariel Rubissow Okamoto

“Small sensors are the foundation of big science,” says Phil Trowbridge, director of the Bay’s Regional Monitoring Program which has just released a new synthesis report on sediment science. The report, combining the results of eight bodies of work, yielded some surprises concerning how much sediment moves from the Sierra and Bay watersheds to the Golden Gate. “The system is calming down after two huge disruptions,” says David Schoellhammer of the U.S. Geological Survey, referring to hydraulic gold mining and dam building. While the supply remains somewhat stable, how much stays in the Bay and how much ends up in the ocean remains an enduring question. In any case, the sediment supply spotlight is slowly shifting from the Central Valley to local tributaries draining into San Francisco Bay. “Our next step is to develop a more accurate model of how sediment moves around the Bay,” says Trowbridge. Mapping out all that we need to know about sediment in order to build wetlands as Bay levels climb is a welcome new priority.

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Supply Side Synthesis

By Ariel Rubissow Okamoto

“Small sensors are the foundation of big science,” says Phil Trowbridge, director of the Bay’s Regional Monitoring Program which has just released a new synthesis report on sediment science. The report, combining the results of eight bodies of work, yielded some surprises concerning how much sediment moves from the Sierra and Bay watersheds to the Golden Gate. “The system is calming down after two huge disruptions,” says David Schoellhammer of the U.S. Geological Survey, referring to hydraulic gold mining and dam building. While the supply remains somewhat stable, how much stays in the Bay and how much ends up in the ocean remains an enduring question. In any case, the sediment supply spotlight is slowly shifting from the Central Valley to local tributaries draining into San Francisco Bay. “Our next step is to develop a more accurate model of how sediment moves around the Bay,” says Trowbridge. Mapping out all that we need to know about sediment in order to build wetlands as Bay levels climb is a welcome new priority.

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About the author

Ariel Rubissow Okamoto is both today’s editor-in-chief and the founding editor of ESTUARY magazine (1992-2001). She enjoys writing in-depth, silo-crossing stories about water, restoration, and science. She’s a co-author of a Natural History of San Francisco Bay (UC Press 2011), frequent contributor of climate change stories to Bay Nature magazine, and occasional essayist for publications like the San Francisco Chronicle (see her Portfolio here). In other lives, she has been a vintner, soccer mom, and waitress. She lives in San Francisco close to the Bay with her architect husband Paul Okamoto.

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