Water service was interrupted along most of the Waianae Coast and police closed Farrington Highway in Nanakuli between Piliokahii and Nanakuli avenues following a break in a 24-inch main Saturday afternoon.
Initially customers from Honokai Hale to Waianae reported outages. Crews were working to restore service through other mains in the area.
Traffic was being re-routed to Pohakunui Avenue and special duty officers were on scene to direct traffic while repairs were underway.
The break was reported at about 4:30 p.m., a Board of Water Supply spokeswoman said. A crew was on its way to the scene.