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same curves indicate that if the flow were unregulated by any dams that this flow rate would correspond to a flood event with about a 20 year return frequency. These curves are presented in Figures 2 and 3. Mokelumne River Prior to 1929, the Mokelumne was not dammed and the river flooded on a frequent basis. The construction of the Pardee Dam in 1929, the Comanche Reservoir in 1962, and levees along much of the banks have restricted the historical flooding. U.S.G.S. has maintained the Woodbridge gauging station since 1926. The first major dam on the Mokelumne River was Pardee Dam, completed in 1930. Figures 4 and 5 show plots of the Annual Peak Discharge and Annual Peak Stage respectively for the period 1926 through 1987 for this gauging station. Also shown for comparison are the completion years of the various dams and the estimated discharge rate or stage resulting from an uncontrolled 2 year return frequency flood. These plots give some idea as to the reduction in flooding that has occurred since the various dams have been built on the Mokelumne. Even allowing for normal variation in precipitation there seems to be a definite reduction in the frequency of peak flow release equaling or exceeding the uncontrolled 20 year flood event. Of course flood control was one of the reasons that the dams were built in the first place. Jahant Slough and Tracy Lakes There is no recorded runoff information for Jahant Slough. However, previous owner Angelo Brovelli said that it would normally require about 20 inches of rainfall per year for Jahant Slough runoff to fill the lakes. This is about twenty-five percent greater than the Buckeye Ranch Resource Plan (November, 1993) 28