The ebb and flow of tides along with beach erosion and flooding in low-lying areas have always been part of life in the islands. And that may be why the creeping threat of sea level rise — spurred by two centuries of unabated carbon emissions around the globe — is sometimes greeted with nonchalance.
But the state Climate Commission’s first statewide assessment of Hawaii’s high susceptibility to sea level rise, released last week, should end any lingering “no worries” shrugs among residents. Even if the state elects to largely go with the flow — making way for a possible sea level rise of 3.2 feet in the middle to latter half of this century — there’s plenty to worry about.
Among the potential statewide impacts linked to that projection: chronic flooding along nearly 40 miles of coastal roads and in some 6,500 structures; displacement of 19,800 residents; and $19 billion in economic losses, excluding hits to public infrastructure. Due to Oahu’s size and extensive urbanization of coastal areas — especially Waikiki and others edging the South Shore — the impact here will be greater than all of the neighbor islands combined, according to the “Hawai‘i Sea Level Rise Vulnerability and Adaptation Report.”
Mandated by state law, the report provides guidance on reducing exposure to sea level rise and increasing our capacity to adapt. It should not be allowed to gather any dust. Rather, the report should serve as a go-to tool or “living document” that’s frequently updated to help us chart strategies for dealing with expected flooding and erosion problems.
Among recommended actions: officially tagging a statewide vulnerability zone through legislative or executive action. Such a move should be supported by state leaders as it can help focus efforts on prepping for a future that will likely require smart urban redevelopment outside of a thrashed vulnerability zone.
Vulnerability designations are already in place in some mainland coastal areas, such as the pancake-flat city of Miami Beach, which is considered ground zero for sea-level rise. To contend with high-tide flooding, that city has raised the height of streets in some areas and installed a network of pumps to send water elsewhere. Also, it has invested more than $400 million to rebuild the city’s storm sewers.
In vast metro areas such as Boston and New York City, city leaders and others are weighing plans for construction of huge sea barriers — one proposal calls for a 10-mile protective arc — around harbors and shoreline areas. In the islands, the inevitable call in shoreline communities to fight off sea level rise with armoring can be expected to touch off emotional debate.
Hundreds of seawalls dotting our coastlines are notorious for eroding sandy beaches and typically unpopular with everyone except landowners protecting waterfront properties. More than 13 miles of beaches have been lost on Kauai, Oahu and Maui to erosion fronting seawalls and other shoreline armoring. And many more miles of beach could be lost with sea level rise, if widespread armoring is allowed, according to the report.
Consensus on how to address climate change could be facilitated by the assembling of public-private partnerships, such as the Waikiki Beach Special District Improvement Association (WBSIDA). Created by city ordinance three years ago, it is seeking public input to forge a Waikiki Beach management plan for decades to come.
Similar beach management districts are taking shape in areas such as Kaanapali, Poipu, Kailua and on Oahu’s North Shore and in mainland communities. Dolan Eversole, a coastal geologist at the University of Hawaii’s Sea Grant Program and WBSIDA coordinator, has said, “It will take these types of new, innovative finance and management frameworks to resolve some of these problems rather than just the government or just private taking all the responsibility.”
Here’s hoping that the Climate Commission’s report redoubles the efforts of Hawaii county and state governments to listen to community voices, heed science and establish policies that effectively balance residential and business-related resiliency with ongoing environmental concerns.
