Failure to protect beaches under slowly rising sea level

Policies to conserve and enhance beaches, public access, and coastal open space are failing in Hawaiʻi according to a recently published study by researchers at the University of Hawaiʻi at Mānoa.

A team of specialists in coastal erosion, sea level rise, and urban planning quantified land use on a section of Oʻahu, Hawaiʻi coast over the period 1928–2015, a time of slowly rising sea level. They concluded that coastal zone management practices in the state, and nationally, will require new policies, or more effective ways for implementing existing policies, in a future characterized by accelerating sea level rise.

U.S. coastal zone management (CZM) relies on an integrated chain of federal to local programs that emphasize beach conservation, public shoreline access, and preservation of open space, as well as other goals. In testing the efficacy of these policies over a century of slow sea level rise, the team found a shift from accreting shorelines and wide beaches in the early data, to expanding erosion and beach loss concurrent with increasing backshore development and seawall construction throughout the period of study—trends at odds with policy objectives.

“The purpose of our study is not to point fingers at Hawaiʻi’s coastal zone managers. We donʻt want to be hard on the people. We want to be hard on the problem. The state’s political leaders, CZM managers, and stakeholders should use the information in this study to update policies so that beach conservation is achieved, and to develop sea level rise adaptation strategies,” said senior author on the study Chip Fletcher, Associate Dean for Academic Affairs and professor of Earth Sciences.

The Hawaiʻi Coastal Zone Management Program (HCZMP), a typical federal-local partnership, was established in 1977 to “provide for the effective management, beneficial use, protection, and development of the coastal zone.” The HCZMP regulates the coastal zone through state and local agencies.

As a state, Hawaiʻi relies heavily on beaches for economic, environmental, and cultural purposes. Rare and endangered species such as the Hawaiian Green Sea Turtle, the Hawaiian Monk Seal, and myriad shorebirds rely on beaches as critical habitat.

“With tourism being Hawaiʻi’s main industry, and beaches providing life-long memories for nearly every child and family, it is perplexing that authority figures have not implemented more effective policies and regulations to ensure beach conservation,” said Alisha Summers, lead author of the study who was an undergraduate student at SOEST while conducting this work.

Read more about it and watch the video report in the UH System News. Brad Romine, coastal management specialist with Hawaiʻi Sea Grant and co-author of the study, and Daniele Spirandelli, assistant professor in the Department of Urban and Regional Planning and extension faculty in Hawaiʻi Sea Grant, are also quoted in the article. Also, read more about it and watch video reports at Hawaii News Now, KHON2, and KITV4.

In a related article, Chip Fletcher comments in The Garden Isle on beach erosion setting back road work on Kauai‘i.