A gas leak that closed parts of Martin Luther King Jr. Boulevard and Hillsborough Street late Monday morning was caused by an Orange Water and Sewer Authority (OWASA) contractor.
The contractor was replacing a water line which runs underneath the asphalt of Hillsborough Street when a crew accidentally struck a gas line and the gas leaked.
“We're replacing a water line to improve the reliability of our drinking water system,” said Marru Darr, OWASA’s director of engineering and planning. “We're installing a new pipe.”
The replaced pipe was an 8 inch distribution pipe, Darr said, 8 inches is the typical size for OWASA distribution pipes. “Transmission pipes are the larger pipes,” she clarified.
Utility piping, wiring and varying works, of differing utility types, laid underneath city and town streets do not automatically run side-by-side nor touch.
Chapel Hill's underground infrastructure is not a busy mess, Darr said. But on Hillsborough Street, in the vicinity of the Monday leak, it is necessary that the water and gas lines do crossover one another.
Their close proximity more than likely had a part to play in the crack through which the gas escaped – through which it leaked.
The intersection where Umstead Drive and Hillsborough Street meet MLK Boulevard and the section of Hillsborough Street falling between Bolinwood Drive and MLK Boulevard were closed to automobiles for a couple of hours.