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Ecological Evaluation of Brovelli Woods P.C. Muick Restoration of Tracy Lakes A key component of the development plans for Brovelli Woods is the "restoration" of Tracy Lakes by maintaining water in the northern lake throughout the year using the southern lake as a reservoir . Approximately 350 acres or forty percent of the property would be covered by the lakes. Robert Belt of Kjeldsen-Sinnock and Associates has written a preliminary restoration and management plan for the lakes which I will briefly summarize. The restoration plan hinges on the idea that the lakes formerly held water throughout the year. The nature of the lakes changed from perennial to seasonal as updrainage alterations were made in the topography of the land (by roads and railroads ) and water was either diverted or captured by up"stream" users . Originally the two lakes were separate and did not connect with either each other or the river except during flood events . A channel connecting the two lakes and a channel draining the southern lake to the river were constructed prior to 1940. The plan proposes to maintain the smaller, northern lake as a permanent water body and use the southern lake as a reservoir for the northern lake. It is likely that in some years the southern lake would contain very little water . However, final plans depend largely on securing a source of water for filling the lakes . The source and amount of water available and the cost of the water will determine the final design for the lake restoration. The major objectives of the restoration plan are to provide a system to supply and maintain the Lake with water and to provide a system for flood control. " (Belt 1989 ) . In addition, the stored water will be used for landscape and golf course irrigatioin , wildlife habitat and recreation. Lake water is not anticipated as a source of domestic water. Kjeldsen-Sinnock and Associates have proposed construction of a small dam, pumping stations and weirs to facilitate water movement and water storage . It remains to be seen if the northern lake bed will be deepened, if the lake bed will be water tight or require sealing, and exactly how much water will come from or be available from the Jahant Slough drainage , Mokelumne River and ground water . More importantly, the exact height or contour to which the lakes will be filled has not yet been decided, although the twenty foot contour has been used to map the lake margins. According to county maps , ground water is at a depth of approximately twenty-five feet beneath the lowest elevations on the property. However, even if ample groundwater is available, it is much more expensive than water from either Jahant Slough or the Mokelumne River. VEGETATION EVALUATION AND ANALYSIS The dominant native vegetation on the property consists of a large oak-buckeye savanna, several vernal pools , a closed canopy oak forest bordering the Mokelumne River, now fragmented by four linear clearings for a golf course , and riparian vegetation located along the margins of the ephemeral lakes. What is unusual about the vegetation is that the oak forest is predominately evergreen, it is the largest remnant riparian forest in San Joaquin County and is highly prized by local birdwatchers. The trees of the savanna are an unusual mix, now locally uncommon: buckeye , blue oak , interior live oak with the more 5