When roadwork doesn’t get done, the effects aren’t always obvious.

Often it takes years for the cracks to appear, for the asphalt to crumble — for the damage to catch up to the neglect.

On Oahu many of the degraded streets and highways giving drivers headaches today stem from budget decisions made years earlier, where public officials opted to kick routine street maintenance down the road in favor of other priorities.

"There’s so much aging infrastructure on this island that people are demanding and screaming (for it) to be fixed," Mayor Kirk Caldwell, who took office in January, said last week. "There’s a lot of competing demands for this money."

And the longer those road fixes are put off, the more costly they become.

"It’s like changing the oil in your car" — if you wait 100,000 miles to fix it, the work will be vastly more expensive, said Ricardo Archilla, an associate professor of civil and environmental engineering at the University of Hawaii. Archilla is consulting the city on its pavement policy. "You want to extend the life as much as possible," he said.

But the city and state did put off the necessary work for more than a decade. Now both are paying extra for that decision as they play catch-up. So are the thousands of motorists who swerve to avoid cracks and potholes on island streets and highways each day.

As a rule of thumb, cities should spend $10,000 on average per lane-mile each year for proper upkeep, according to Stephen Muench, an associate professor at the University of Washington. (Several years ago Muench helped Hono­lulu officials develop standards for new paved roads. It required that new roads built from scratch be thicker and more durable.)

The city of Honolulu oversaw more than 3,000 lane-miles in 2002. It budgeted about $6 million that year to maintain them. It then boosted that amount to $30 million in 2006 and $44 million in 2007. The budget kept climbing: $77 million in 2009, $100 million in 2013.

Next year, as the city continues to try to dig its way out of the road-repair hole created years ago, Caldwell has proposed $150 million to repave more than 300 lane-miles of bad road.

The state Department of Transportation faces a similar effort to catch up. It maintains the islands’ larger thoroughfares such as the H-1 and Pali, Kame­ha­meha and Farrington highways on Oahu — major roads that elicit some of the worst complaints from motorists.

"The state is currently facing a large backlog of highway maintenance work, repairs, reconstruction and bridgework, which was affected by the recession but is also an ongoing issue," Hawaii DOT spokes­woman Caroline Sluyter said.

From 1996 to 2003 state leaders diverted more than $143 million from the State Highways Special Fund — the account used to operate, maintain and repair state-run roads — to the state’s general fund. They further diverted $10 million from the fund in 2006.

Former Gov. Ben Caye­tano, who was in office most of those years, said the transfers helped at the time to salvage social programs, avoid education cuts and pay out raises given to public-sector unions through mandatory arbitration law. The move hurt highway work, but it was necessary for Hawaii to balance its budget as it coped with economic stagnation and a dearth of Japa­nese tourism in the mid-’90s, Cayetano said.

"I had to make some tough decisions," he said this month, reflecting on the state highway transfers. After he left office, "it was pretty much understood that the money that we took from the highway fund, that would be made up with an increase in the fuel tax" under his successor, Linda Lingle, Caye­tano said. But that increase didn’t happen. "Taxes should have gotten raised in the aftermath because the economy was better," he added.

Lingle could not be reached for comment.

Now, with the help of recent increases to vehicle weight taxes and registration fees, the state is boosting its road-repair budget and projects, transportation officials say. Like the city, it’s trying to get back on track.

It spent nearly $54 million on highway and bridge maintenance in 2011 and more than $48 million in 2012. This year the state expects to spend $86 million on that work, making it "better equipped to address our … needs although still in catch up mode," Sluyter said in a recent email.

The department has planned repairs to the H-1 and its overpasses at McCully, Kee­au­moku and Nuu­anu during spring. It also has major resurfacing scheduled this fall for Kame­­ha­- meha Highway from Wai­hau to Ka Uka, and Kalanianaole Highway from West Hind Drive to near Hanauma Bay Road.

The department also has shallow surface repairs planned for Pali Highway this fall, ahead of a larger and more comprehensive resurfacing in fall 2014, and several other highway projects in the works.

There were other factors that helped lead to Hawaii’s roads being in such poor shape.

"It’s a combination of increased population, increased traffic," city Department of Facility Maintenance Director Ross Sasa­mura said recently. "There are bigger and heavier vehicles using the road today than what was in place and what was in use when they were originally designed."

With Oahu’s space limitations, cars and trucks often have to share the same roads, he said, while some of downtown Hono­lulu’s roads are more than a century old. "We were doing fairly well in maintaining streets up until the 1980s," when a population boom brought unprecedented traffic to the island, Sasa­mura added.

Recent increases in vehicle fuel efficiency — a national goal to help reduce greenhouse gas emissions — has also led to fewer gas tax revenues for roadwork nationwide, including Hawaii, said Hamid Baha­dori, a Los Angeles-based transportation engineer for the Auto Club of America. Those gas tax revenues are going down at the same time construction costs are rising, he said.

The recent recession both helped and hurt road maintenance, Baha­dori said. It eroded the tax dollars used for roadwork, but it also reduced the wear and tear on roads, with drivers logging fewer miles in their cars, he said.

"I don’t think anyone willingly disregards the need for roads," Sasa­mura said, "but there are other things that place demands."

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