A water main break always disrupts affected neighborhoods and upsets a limited number of customers. But when it happens in a particularly bad spot, where its impact is felt much more widely, it sounds an alarm that Honolulu needs to get ahead of the problem, as much as possible.

In addition, water authorities need to amplify communications with the public, whose daily lives are upheaved during such incidents.

This was the case with the rupturing early Saturday of a 24-inch line between Kilauea Avenue and Waikui Street — which, unfortunately, is located just after the H-1 merges into Kalanianaole Highway.

And that, as an arterial connecting Honolulu with East Oahu communities, meant residents on that end of the island had to reroute drastically. Even worse, the backup caused by the forced detour off the H-1 eastbound lanes translated into standstill traffic for hours, over the course of several days.

The Honolulu Board of Water Supply (BWS) had other problems over the weekend, as if to underscore the fact of aging infrastructure: additional water-main breaks on Queen Street in Kakaako, and 10th Avenue in Palolo Valley.

All of this strongly suggests that time is of the essence in developing a rational plan for financing and completing repairs to the water delivery system — and that the water board must accelerate its pace toward that goal.

Water pipe failure is fairly unpredictable. The Waikui line, installed in 1969, was of fairly average age among the 2,100 miles of underground pipes and had never sprung a leak. Ernie Lau, BWS chief engineer, said analysis of the cause is still underway.

There was an abandoned pipeline in place that complicated repair. Lau said it was noted in historical documents, but those are consulted in advance generally for planned replacements rather than an emergency response such as this.

But the agency, well aware of the need for ongoing overhaul of a deteriorating system, in October published a 30-year master plan. According to the document, a risk assessment of the system was conducted, scoring pipelines according to a set of technical criteria.

Age is a factor, but not the only one: There are century-old pipes that are at less risk than newer lines, because of the surrounding soil or rock conditions and other elements, Lau said.

In the coming months the board will complete a financial plan that costs out needed repairs and calculates different strategies for raising revenue. Lau said a balance will have to be struck between the aging system’s critical needs and affordability — how high rates can go without straining affordability.

The water board is entirely rate-supported, with no tax funds. So the ratepayer will need to stay engaged in that process.

The agency has to make up for lost time in bringing the water-line network into reasonable condition. Before the 5-year series of rate increases that ended in July 2015, the water board had let 11 years go by without a rate increase.

This deferred maintenance might have been the most palatable option during economic doldrums of a decade ago, but that can’t continue as policy.

BWS officials are rightly undergoing a postmortem review of the current crisis, once traffic patterns are restored as expected today.

But already, Lau acknowledges one area of needed improvement: communications with the public. Alerts went out on various traditional and social media channels, but he said they should be even more frequent.

We would concur with that conclusion. Few things are as crucial to daily living as reliable water service. And when disruptions to that service are compounded with massive traffic jams, the public deserves notification early and often. The Board of Water Supply must supply that assurance as well.