This report presents precipitation data for the San Francisco Bay region in a form suitable for use as criteria for both drainage design and the study of the stability of land slopes. The data presented include (1) an isohyetal map showing long-term mean annual precipitation and (2) a table of storm precipitation depths, corresponding to various durations and frequencies, that are applicable to any site in the region. The regimen of precipitation in the region is such that depth-duration frequency characteristics for a site are closely related to the mean annual precipitation for that site.