Wai'anae Coast residents are being asked to conserve water through tomorrow morning, as crews yesterday continued to make repairs to the area's primary water transmission pipeline.

Work on the ruptured 24-inch main was also affecting traffic, adding to lane closures and contraflowing taking place on Farrington Highway during the Board of Water Supply's three-year pipe replacement project, scheduled to June 2011.

Patty Teruya, a longtime Nanakuli resident and chairwoman of the Nanakuli-Ma'ili Neighborhood Board, said being asked to conserve water and deal with contraflow traffic on Farrington Highway is nothing new for the Wai'anae Coast.

"It happens so often it feels like we're living on the steel plates that construction crews use on roads," Teruya said.

The 24-inch main broke Wednesday afternoon near Honokai Hale. The Board of Water Supply asked residents from Honokai Hale to Makaha to use water sparingly, and repair crews set up a contraflow lane from La'aloa to Ali'inui streets.

Crews had to dig down 12 feet to reach the pipe, and found that the break was on the underside of the pipe, requiring more digging, said Tracy Burgo, Board of Water Supply spokeswoman.

The pipe, installed in 1961, supplies the Leeward Coast with 60 percent of its drinking water, Burgo said. It was scheduled for replacement soon, under the ongoing $24 million water main project under Farrington Highway.

"Breaks like this are what we've been trying to avoid by replacing the old pipe," Burgo said.

Burgo praised Leeward residents for conserving water, using it only for the essential needs of cooking, drinking and bathing.

"It's critical to conserve," she said. "Right now the 40 percent we get from other places plus the reservoirs is enough, but you're never sure how long repairs will take."

Teruya said, "It's very scary having to conserve water like this because water is so critical to all of us. You can live without food for a few days and you can deal with traffic, but you can't live without water. You've got 55,000 people on the Leeward Coast who have no choice now but to conserve and deal with the traffic mess."

Teruya said the city should have replaced the water main long ago.

"We know the pipe needs to be replaced, it's been neglected too long, but I don't know why they waited so long to do it. The former administration should have done it long ago," she said. "This is our only road in and out. Maybe it's time they look at a mauka highway or something because Farrington is always having a water break, road repairs or Hawaiian Electric is working on poles or something. We're not happy campers."

Phase 1 of the water main replacement project began in March and covers the one-mile stretch from the entrance of Ko Olina Resort at Ali'inui Drive to the end of H-1 Freeway. Phase 1 is expected to take 15 months to complete.

Phase 2, which began in June and is scheduled to last 14 months, consists of a 1.25-mile stretch from Haleakala Avenue in Nanakuli and Piliokahi Avenue (Black Rock).

The project's third phase, a nearly two-mile stretch between Ali'inui Drive and Piliokahi Avenue, is expected to begin in August 2009 and last about 22 months.