桃山水库自１９９０年建成以来，在城市供水、削减洪峰，灌溉等方面了取得了显著社会经济效益。运行中１９９４年和１９９５年两次发展坝后排渗沟左端浑水渗出的异常现象，结合测压管理设，采用非标准贯入、含水量、干密度测定、注水试验等常规手段，通过对水和土样的化学分析，查明了原因． Since its establishment in 1990, the Taoshan Reservoir has made remarkable socio-economic benefits in urban water supply, flood reduction and irrigation. During the operation, two anomalous phenomena such as muddy water exudation at the left end of drainage ditch in 1994 and 1995 were developed. Combined with manometry management, we adopted conventional methods such as non-standard penetration, water content, dry density determination and water injection test. Chemical analysis of water and soil samples identified the cause.