2. Investigation
2.1. Visual examination
Fig. 2a and bshows of the location of leakages of the water pipe line. The representative failed section pipe was received for investigation is shown in Fig. 3a. Visual examination revealed severe localized pitting attacks at the inner surface of the pipe. These pitting attacks took place only in the upper half of the pipe inner surface between the 9 and 3 o’clock positions. Whereas, smooth deposits were observed on lower half of the inner surface of the pipe as shown Fig. 3b.