San Rafael Rock Quarry, California

The only major rock quarry to be found in the San Francisco Bay featuring direct water access and barging facilities, the San Rafael Quarry supplies rock and pavement products for construction projects all over the bay. The Dutra Company is a major mover of material around the bay, starting with clamshell dredges working in the Delta a hundred years ago, and now involved in marine construction, bridge repair, levee maintenance, dredging, and other shoreline engineering projects. The company's fleet of dredges and barge-mounted cranes are in use all over the bay and beyond: from Oakland's harbor deepening, to the third harbor tunnel project in Boston, where equipment was shipped from San Francisco through the Panama Canal. The Dutra Company has owned the pit since 1986, but it has been in operation for over 100 years, and the pit is now 200 feet deep. Dutra expects to continue to quarry at the site for at least another 25 years, after which the side of the pit next to the bay would be breached, and the pit flooded to become a very deep yacht harbor.