It is essential to have a proper survey and diagnose the area where the water tank is being leaked and then move towards the rectification of the tank. The survey should be done both externally and internally within the overhead tank. It is to be ensured that the overhead tank is dry prior to the internal inspection so that any areas of the leakage can be identified easily.
During the inspection cracks within the overhead tank, leakage from the pipe inlets and outlets, and the condition of the chamfers along with the condition of the internal plaster need to be diagnosed thoroughly. Once the diagnosis of the problems has been done, working towards the rectifications of these problems can be done.