Officials say Friday’s collapse of Kamehameha Highway in Hauula from coastal erosion is merely a preview of what’s to come as climate change and rising sea levels accelerate into the future.
“This is what climate change looks like,” said Joshua Stanbro, chief resilience officer and executive director of the city Office of Climate Change. “As an island community we’re on the front lines, and we’re seeing it in real time.”
With some 250 miles of oceanfront roads under threat of shoreline erosion, the state Department of Transportation has a tiger by the tail.
Ed Sniffen, DOT deputy director for highways, admitted earlier this week that the department has had a difficult time keeping up with the growing problem.
>> Photo Gallery and Video: Work begins on collapsed highway in Hauula
Indeed, the section of state highway in Hauula was identified as the state’s most critically threatened stretch of road in a report to the DOT nearly two years ago.
The Statewide Coastal Highway Program Report, spearheaded by University of Hawaii engineering professor Oceana Francis, was updated this summer with the Hauula section remaining the top priority.
The report warns that the estimated cost for delaying improvements until severe damage develops may be “50 times or higher than the cost of implementing preventive measures now, not to mention traffic interruption, inconvenience, safety concerns and business losses.”
Meanwhile, the DOT announced Monday that additional segments of the roadway will be added to the emergency repairs for a total of 1,500 feet, boosting total costs for the temporary project to $600,000.
“Adding 1,200 feet of repairs is necessary to ensure another collapse doesn’t happen with the next swell or storm system,” Sniffen said in a news release.
There was no word on when more permanent repairs are planned for the Hauula section.
Bradley Romine, coastal geologist and coastal management specialist with the University of Hawaii Sea Grant College Program, said the state faces a huge challenge in maintaining access for communities along vulnerable coastal highways.
Romine said proactive long-term planning for place-based adaptation strategies is needed by agencies, stakeholders and communities.
“These problems are sure to only worsen with ongoing climate change and sea level rise,” he said.
Chip Fletcher, associate dean and professor in UH’s School of Ocean and Earth Science and Technology, said Hauula is a living laboratory and a blueprint for the challenges we face as sea level rise worsens in the next couple of decades.
But the Hauula area, like many other low-lying coastal areas in Hawaii, has another related climate-change issue that must inevitably be addressed.
“The community is vulnerable to a rising water table,” he said, adding that the area — situated between the mountain and the sea, already has shown to be susceptible to groundwater flooding. “The ocean is rising and so is the groundwater. This community has extremely difficult challenges ahead.”
Fletcher said further studies are needed to determine how close Hauula’s water table is to the ground surface.
There have been a number of studies that show Hawaii’s coastlines will be especially vulnerable as climate change worsens:
>> A 2017 report for the Hawaii Climate Commission found that potential impacts on Oahu of 3.2 feet of sea level rise include the loss of $12.9 billion in structures and land; 3,800 structures, including hotels in Waikiki; the displacement of 13,300 residents; and the loss of 17.7 miles of major roads.
>> A 2018 study by University of Hawaii researchers found a third of the state’s shorelines vulnerable.
>> Another 2018 study by UH researchers examined a 5-mile stretch of reef-fronted shoreline from Hauula to Makalii Point and found accelerated erosion in the last 40 years.
Stanbro said adapting to climate change will not be inexpensive, and that’s why he supports Honolulu Mayor Kirk Caldwell’s plan to sue the fossil fuel companies for damage caused by climate change and rising sea levels traced back to corporate action or inaction.
“It’s like death by a thousand cuts,” Stanbro said of the repairs Hawaii faces. “These fixes are costing millions, and they’re coming out of the taxpayers’ coffers when they should be coming from the oil companies.”