O'ahu's aging water mains failing nearly every day

By Robbie Dingeman
Advertiser City Hall Writer

Water mains burst and gush on O'ahu nearly every day.

The Board of Water Supply is replacing deteriorating pipes with ones made of plastic in areas that are more prone to water main breaks, such as Hawai'i Kai. Eugene Tanner • The Honolulu Advertiser

But so far this summer, Honolulu water crews have battled more than the usual number of major breaks. Nearly a dozen breaks that have disrupted the routines of thousands of people have occurred since Memorial Day weekend, when a 12-inch main ruptured near the new Consolidated Theatres' Ward 16 complex on Auahi Street on its opening weekend.

Since June, Kalihi has been hit by four breaks. Three have disrupted the Wai'anae Coast. A sinkhole created by a broken main opened in the middle of Farrington Highway on July 14, cutting off the only major access road to Makaha. Again.

With some water mains now more than 100 years old, the Honolulu Board of Water Supply is in the midst of an ambitious pipe replacement program that touches nearly every neighborhood on the island. The most visible project is the replacement of pipes along King Street from Chinatown through downtown.

A decade ago, the board spent less than $17 million annually on pipe replacement. About 500 water main breaks typically occurred each year.

In 1999, the agency budgeted $55 million for construction, including $35 million for the replacement of aging water mains. The number of breaks dropped to about 400 a year. Since 1997, the number of miles of pipe replaced because of water main breaks has been more than 10 miles each year compared to about half that much during the early 1990s.

"It's (large main breaks) just been more visible, but we've always had about a break a day for the past 10 years," said Howard Tanaka, head of the Honolulu Board of Water Supply's maintenance engineering branch.

Tanaka said deteriorating pipes are more likely in certain areas: on the Leeward Coast along Farrington Highway, parts of Hawai'i Kai, Kalihi and Pearl City.

In coastal areas, more breaks occur because salt water underground corrodes pipes faster. Sometimes there's more coral in the ground and the higher alkalinity eats away at the pipes, Tanaka said. Communities built on land created with fill are more prone to breaks because the land settles and cracks the pipes.

Tanaka said water lines usually need to be replaced about every 50 years. But some pipes in some places last longer.

"In town, we do have 100-year-old pipes while in Hawai'i Kai after 15 years, some of those mains were breaking," he said.

In areas where the pipes deteriorate fastest, the board is using plastic pipe because it doesn't rust.

Tanaka said the board has gone from budgeting and planning for one year to scheduling repairs and construction over six years. "It's a better planning process than to be short-term reactionary," Tanaka said.

The board also is making leak-detection a priority. Tanaka described a continuing survey of all the pipes with computer equipment that helps detect small leaks before they become the big break "that disrupts traffic and disrupts everybody's life."

Homes and businesses connected to the city water system pay for its operation and maintenance. Rates have not increased since 1995.

O'ahu residential water customers pay $1.77 per 1,000 gallons for the first 13,000 gallons, then $2.12 per 1,000 gallons. After 30,000 gallons, the rate goes up to $3.18.

City Council Chairman Jon Yoshimura said he believes the agency could do more to prevent breaks. But overall, he said, he is impressed by the performance of the semi-autonomous city agency that handles water delivery. He watched as workers quickly repaired a break around the corner from his Makiki apartment.

"I was amazed at how quickly they were able to cut off the water, dig up the pipe, fix the problem and get the water back on," Yoshimura said.

Reach Robbie Dingeman at rdingeman@honoluluadvertiser.com or 525-8070.