Windward highway crumbling as ocean swell nears

In the 23 years that Arish Riordan has lived in Kaaawa on Kamehameha Highway’s mauka side, she’s watched the beach her family used to enjoy there gradually disappear, replaced by piles of large boulders installed to protect the roadway from the encroaching sea and pummeling surf.

Until this year Riordan never saw parts of the highway fronting her family’s home on rural Kualoa Ranch-owned property actually swallowed by the ocean. However, in the past several weeks the heavy surf has already collapsed two giant chunks of asphalt road and guardrail about 100 feet apart, prompting single lane closures there. The latest closure on that highway, which offers the only route across Oahu’s Windward coast, is expected to last a week as state crews do repairs.

“Honestly, I just wish I had my beach back,” Riordan said Monday. “I’ve never seen it so strong. We are at the mercy of the waves. I don’t know what you can do to stop it from happening.”

The Windward Coast’s recent highway collapses are the latest reminders of the huge challenges that the nation’s only island state faces due to sea-level rise and climate change, according to various officials. Some North Shore residents also are fighting to keep their homes on dry land, and Waikiki officials pour tons of sand to preserve the beaches there.

The situation could get worse tonight. The north-facing shores of Oahu, which include the coast north of Kaneohe Bay, are under a high-surf warning until 6 p.m. Wednesday, with waves of 30 to 40 feet expected.

“I’m not at all surprised at what’s happened with that highway,” said Chip Fletcher, an associate dean and geology professor at the University of Hawaii. “What we’re seeing in Kaaawa is an example of what we’re going to begin to see in more and more places as we move forward.”

The coastal highway between Kaaawa and the Crouching Lion is arguably one of Oahu’s most scenic routes, but according to Fletcher it’s currently one of most vulnerable state areas to the “slow-motion disaster” of sea-level rise.

Nonetheless, various public agencies are playing catch-up to respond.

State Department of Transportation crews have been filling the highway’s collapsed areas with a cementlike material, but it’s considered only a short-term fix. DOT officials say they’re working on long-term fixes and that they’re coordinating with federal, state and county officials to ensure they follow the proper permitting steps.

The DOT had expected to start design and planning work on such a long-term project in three years, but now it aims to start sometime next year instead, according to agency spokesman Tim Sakahara.

“It’s a very complex issue,” Sakahara said Monday. “We don’t want to go in and spend a billion dollars on a new highway only for scientists to come in and say that that stretch … is still in an area of concern. So really, we need more information.”

Meanwhile, the 15 county and state agencies that make up Hawaii’s Interagency Climate Adaptation Committee, which is tasked with finding ways to deal with climate change, aren’t slated to release their first report, on the state’s sea-rise vulnerability, until the end of 2017. State Rep. Chris Lee, who’s a strong supporter of the committee, said it’s currently funded at about $500,000 but that lawmakers have recently discussed increasing the funding by $200,000 to accelerate the work and get more data.

“Speed is of the essence,” but “nothing is in stone” for getting those added dollars, Lee (D, Kai­lua-Lani­kai-Wai­ma­nalo) said Monday.

Kamehameha Highway on the central Windward coast presents a tough challenge because it’s tightly squeezed between the coast and private properties, leaving it no place to retreat from the rising sea, officials say. “There’s not a lot of space to work with,” Sakahara said.

Hawaii Gov. David Ige also addressed the issue Monday. “I think the challenge is how do we get from where we are today, with all the highways along the coast, to where we want to be with some reasonable setback that will protect those assets?” Ige said while briefing reporters.

Northbound Kamehameha Highway near Kaaawa Valley Road and Kanenelu Beach will remain closed for about a week, reducing the highway to one lane, according to a DOT release. A previous closure occurred there in mid-February after high surf washed over the area. Local residents and workers reported minimal headaches from the contra-flow so far. Jodi Wade, postmaster at the Kaaawa Post Office, said it would be “horrific” to lose Kamehameha Highway.

“If it’s permanently out, this community would be closed off,” she said. Similar damage near the Crouching Lion led to months of repair work last year.

“It’s just going to keep breaking — there’s nothing you can do about it,” Kayla Kamaka‘ala, a 33-year-old lifelong resident of the area, said while leaving mail there. “If you drive and you look at (the road) carefully, it’s cracking in a lot of places.”

Fletcher said he was surprised that the state’s wall of boulders has helped keep the road from crumbling for as long as it has. Any long-term solution could be costly, he said. Fletcher said that he believed “the benefit-cost ratio leans in favor of keeping the road where it is and continuing to find a way to protect that road.”

Protective seawalls typically act to further erode other nearby beaches — but where the Kaaawa road is crumbling, there aren’t any nearby beaches left, he added.

“I think we are at a rock and a hard place here,” Fletcher said.

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Star-Advertiser reporter Sophie Cocke contributed to this report.