Mallard II is a wooden-hulled clamshell dredger[2] used to maintain levees on the San Francisco Bay Salt Ponds.

[6]: 51  The steel frame was installed by Bethelehem Pacific's San Francisco shipyard in 1954, at which point she maintained levees on over 30,000 acres (12,000 ha) of ponds in the South Bay as well as Napa County.

[8] Mallard II was used to construct such watercourses as North Creek; in 1972 she was briefly idled while the Leslie Salt Company sought dredging permits from the United States Army Corps of Engineers.

[5]: 45  In addition to their role in operating the salt ponds, the levees protect Bay Area cities like San Jose from being flooded by high tides.

[14] A December 2020 permit for a wetlands project issued by the California Department of Fish and Wildlife provided for maintenance of salt ponds to be carried out by the still-operational Mallard II, using the existing system of dredge locks, referred to as "the most technologically and economically feasible method for solar salt production in south San Francisco Bay".