Sediment transport of streams tributary to San Francisco, San Pablo, and Suisun Bays, California, 1909-66

sediment transport and streamflow . During 1909-66, sediment was transported to the entir e San Francisco Bay system at an average rate of 8 . 6 million cubic yards per year . The Sacramento and San Joaquin River basins provided about 83 percent of the sediment inflow t o the system annually during 1957-66 and 86 percent during 1909-66 . About 98 percent of this inf low was measur ed or estimated at sediment measuring sites . Measured sediment inf low direc tly to the bays c omprised only about 40 perc ent of the total discharged by ba sins direc tly tributary to the bays . About 90 per c ent of the total sediment disc harge to the delta and the bays in the San Francisc o Bay system thus was determined on the basis of systematic measurements. 17 .