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Introduction This report presents a brief overview of the historical land use and general hydrology of Tracy Lake , and outlines a Water Management Plan designed to restore the lake to its "pre-dam" , natural state. Restoration of the lake is a primary goal in an overall development plan for the surrounding land that includes a private golf course and 26 private residences . Hydrology Tracy Lake , shown in Figure 1 , actually consists of two separate lake areas that represent the terminal drainage sink for the Jahant Slough watershed. The northern area (North Lake) drains an area of approximately 1 square mile. When full , at elevation +25 feet (U. S .G . S . Datum) , North Lake contains approximately 600 acre feet of water and covers an area of approximately 85 acres . The southern area, (South Lake) drains an area of approximately 16 . 5 square miles . When full , at elevation +25 feet , South Lake contains about 1 , 700 acre feet of water and covers an area of approximately 265 acres . Historically, the two bodies of water would have been joined in the winter or spring when the water level was relatively high and would have become separated as the water level receded during the summer months . Examination of topographic contour maps indicates that during large flood events , overflow from Dry Creek, which lies about 1 mile to the north , probably enters the Jahant Slough drainage . This is also suggested by examination of aerial photographs taken in 1940 that ' reveal Valley Oak woodlands connecting the two drainage systems along natural drainage corridors . The lakes appear to have been formed from sediment deposition during historical flooding of the Mokelumne River that formed a barrier across Jahant Slough. This theory is supported by fact that the soil between the lakes and the river consists of a sandy organic loam extending to a depth of at least 20 feet along the bank of the river , while the soil in the lakes consists of fine silty clay loam which is more typical of the Jahant Slough drainage basin soil type . Furthermore the area between the lakes and the river contain remnants of several large oxbows which were once river channels and are now covered with a dense riparian forest community. This is in stark contrast to the surrounding Oak-Buckeye Savanna which surrounds the majority of the lakes . During periods of historically significant runoff , Tracy Lake has overflowed into the Mokelumne River and vice-versa. The previous land owner, Angelo Brovelli , said that during the large flood of 1950 the river overflowed into the lake, completely filling it. He also reported that prior to construction of the dams upstream, the Mokelumne River would flood the whole area quite frequently, and that the levee that runs along the western and northern edge of the lake 1