1980年夏天，华盛顿郊区卫生委员会（WSSC）将日尔曼镇高架水箱投入运行。在运行的前几个月，水箱中的水位很少超过设计最高水位以下3m的水位。本文描述了WSSC为确定该问题的原因而进行的调查。调查采用了计算机建模技术。根据建模结果，开始了深入的实地调查。最终，现场调查发现，通往Germantown储罐的900 mm管道上的一个阀门被意外关闭，储罐附近的一个泄压阀被设置为打开，从标高2处的分配系统中放水。 水箱最高水位以下1m。此后，这两个问题都得到了解决，油箱现在已加注至最大液位。包括数字。

In the summer of 1980, the Washington Suburban Sanitary Commission (WSSC) put the Germantown elevated tank into operation. During the first several months of operation, the water level in the tank rarely exceeds an elevation of 3 m below the maximum water elevation for which it was designed. The article describes the investigation conducted by WSSC to determine the cause of this problem. The investigation utilized computer modeling techniques. Based on the results of the modeling, an intensive field investigation was begun. Eventually the field investigation found that a valve on a 900 mm pipe leading to the Germantown tank was unintentionally closed and a pressure relief valve close to the tank was set to open, releasing water from the distribution system at an elevation 2.1 m below the maximum water level in the tank. Both of these problems have since been remedied and the tank now fills to its maximum level. Includes figures.