Water Main Break
A water main break is a disaster. The water main is an underground pipe that delivers water to the customer’s service pipe. In residential areas it
usually runs under the street. If a hole or crack develops in the pipe, the water will typically find its way to the
surface. Because the water main is under pressure, water will continue to flow until the break is repaired.
If water needs to be turned off for a water main break, homeowners will receive little or no notice. The water
can flood streets and private property causing damage and safety hazards, and must be controlled as quickly
After a water main break, customers may notice brown or cloudy water coming from their tap. If so, they should
not use appliances or drink the water until it runs clear.
Orange Water and Sewer Authority, North Carolina has over 15,000 valves in the water system.
Water main breaks usually result from external corrosion of the pipe. Chapel Hill, soil is highly conductive and
corrodes the metallic pipe from the outside in. Changing soil conditions can then cause the weakened pipe to
Water main breaks are more likely to occur when frost penetrates deep into the ground, to a level of 3-5 feet,
usually from late January until early April. While cold temperatures may send the frost deeper, the level of
snow cover is also important. Snow will act as a “blanket” insulating the ground. In years when there is plenty
of snow, the frost does not go as deep.
First we control the water by closing valves. Then we contact other utilities to make sure we can dig without damaging other services or endangering staff or the public. We find the leak using an electronic leak detector, and then dig down to the pipe. Depending on the type of failure, we may apply a repair clamp or replace a length of pipe.We have been able to reduce water main breaks by replacing and repairing corroded mains with new Ductile Iron Concrete Lined pipe (DICL).