Pending revisions to the Hawaii County planning rules could result in developments being pushed farther away from the coast in an effort to mitigate the impacts of climate change.
The revisions, which will be discussed Thursday at a joint meeting of the Windward and Leeward Planning Commissions, have been proposed in order to conform with Act 16, a law passed by the state Legislature in 2020 that expanded the state’s coastal zone management laws.
Most significantly among the changes is a doubling of the county’s minimum shoreline setback: Where current developments must be located at least 20 feet inland from a shoreline, the new rules would increase that margin to 40 feet.
In addition, existing shoreline lots will not be granted exemptions to the new boundaries if the new setback encompasses more than 50% of the property.
According to statements by the Planning Department, there are no exceptions for any new development. Preexisting developments built in the 20-foot setback area — for example, many parcels along Alii Drive in Kailua-Kona — can be repaired and maintained, but cannot be enlarged, rebuilt or replaced without obtaining a shoreline setback variance from the county.
In addition to the larger setback, the new rules also include updated definitions of certain basic terms in order to better control what can and can’t be built along the island’s shorelines.
For example, the current definition of “development” does not include single-family dwellings smaller than 7,500 square feet, which therefore means that such dwellings do not require a special management area permit.
The updated definition of “development,” however, closes this exemption by requiring that all single-family dwellings, regardless of size, receive an SMA permit if they are situated on a shoreline parcel or a parcel impacted by ocean waves, storm surges and the like.
Meanwhile, the new rules also offer definitions of “beach” and “coastal hazard,” which are absent from from the current rules.
“Adding a definition of ‘beach’ will prevent future loss of sand by protecting these areas from shoreline hardening structures and will prevent landscaping from adjacent private lands from impeding into the beach transit corridor where the public can walk along the shoreline,” according to a statement by the Planning Department.
Much of Act 16 and the updated rules are directed at combating “shoreline hardening,” the process of building armored structures such as seawalls to protect shoreline infrastructure from coastal hazards. Such processes often have negative impacts on native species’ habitats and can actually accelerate, rather than hinder, erosion in certain places.
“According to a 2012 study by (the U.S. Geological Survey and the University of Hawaii), 75% of beaches in Hawaii are undergoing a trend of chronic sand loss and shoreline retreat,” read the Planning Department’s statement. “Preventing shoreline hardening structures on sand beaches will prevent further beach loss.”
Should the joint commission approve the rule changes Thursday, the Planning Department will hold a community hearing about the updated rules.
The proposed rule changes can be viewed at tinyurl.com/5n7ram8y.
Email Michael Brestovansky at mbrestovansky@hawaiitribune-herald.com.