A study of the flood hydrology of Lucerne Valley, Calif., was made to develop the 100-year stage for Lucerne Lake. Synthetic-hydrologic techniques were used; and the 100-year flood stage was estimated to be at an elevation of 2,849.3 feet above mean sea level. Channel dimensions were measured at 59 sites in Lucerne Valley. Dranage area-discharge relations developed from channel-geometry data for sites nearby were used to estimate the discharge at 12 additional sites where channel geometry could not be measured. In order to compute the total volume discharge into the playa, the peak discharges were converted to volumes. From the Apple Valley report (Busby, 1975) the equation formulated from the relation between peak discharge and flood volume for the deserts of California was used to compute the flood volumes for routing into Lucerne Lake. (Woodard-USGS)