Board of Water Supply crews were repairing a 12-inch main break near 98-1611 Kaahumanu Street between Hoolauae Street and Laauhuahua Place Friday afternoon.
Crews have closed the two makai-bound lanes and are contraflowing the mauka-bound lanes.
The break was reported at around 11 a.m. The main was originally installed in 1973.
About 50 customers are affected. A water wagon will be placed in the area to provide water for affected customers.
Motorists are advised to exercise caution when traveling through the work area. Repairs are expected to continue overnight into Saturday morning.
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