The 36-inch transmission main — the same size as the large pipe that burst and shut down N. Glebe Road near Chain Bridge in November — was placed out of service in 2013 due to concerns about a catastrophic failure. A transmission line was built parallel to it after a major water main break on N. Old Glebe Road in 2009 and is currently providing service to the area.
County officials say rehabbing the old main, which was built in 1972, will help provide redundancy in the county’s water system. Arlington’s water comes from the Washington Aqueduct in D.C., by way of pipes that cross the Potomac River at Chain Bridge then branch out to various parts of the county.