Water Main Repaired, Service Restored on South Oak Street

By SCOTT TAYLOR
Falls Church Times Staff

January 13, 2010

A water main break on South Oak Street provided an unexpected complication Wednesday afternoon for local residents returning home and commuters who use the street as a cut through between Lee Highway and West Broad Street.  More to the point, some local homeowners experienced an evening without running water.

The break was reported at approximately 5:00 p.m. and City of Falls Church crews responded to identify which water main under South Oak Street had been compromised.  Robert Goff, Director of Operations for the City, explained the process on his laptop as crews jack hammered through the pavement some 25 feet away.

“There are two mains under the street – one is six inch cast iron and the other is sixteen inch ductile iron,” Goff explained.  “The main that broke is original (cast iron) pipe that dates to the early 1940s.”

Ductile iron is flexible and elastic; cast iron is brittle.  If a pipe breaks under the street due to environmental temperature fluctuations, it is in all probability a cast iron main.  The ductile iron main on South Oak Street was installed in 1972.

‘This is a circumferential break,” Goff said before the crew had even reached the breached pipe.  His professional assessment – confirmed after the asphalt and soil had been excavated – was based on the volume of water running down the street over the previous hours.  A circumferential break is like slicing through a pipe top to bottom, which releases less water than a break that runs horizontally through some length of the pipe.

Water service was restored to homeowners by 9:00 p.m. and South Oak Street was ready for another morning commute and the arrival of the Thursday Thomas Jefferson Elementary School student buses.