Two examples of water main failures are shown.
The first water main developed a leak after 8 years of service. Although primed and tape-wrapped for corrosion protection, the pipe surface showed extensive pitting and corrosion damage. In contrast, the inside of the pipe was undamaged. The resistivity of the soil was measured. Based upon the readings, the soil was found to be corrosive. It was recommended that the water main be cathodically protected to prevent future failures.
The second water main was in place since the 1920s. It was bare cast iron, buried beneath the foundation of a home. When the pipe began to leak it caused the surrounding soil to settle and the foundation of the home above it to crack. In this instance, the hole in the water main started on the inside surface.