After the Lahaina fire that took so many innocent lives, doesn’t it bother you to hear government officials expressing surprise, that they didn’t realize that those circumstances could occur, but that “we will investigate to make sure this never happens again”? The problem is rooted in what is called “normalcy bias,” the reluctance to consider natural hazards greater than what occurred in the past.

On Oahu, great tsunamis present the greatest risk of loss of life during an evacuation, which could result in an unprecedented number of fatalities in Honolulu. Will you survive? How can we make the odds better for everyone?

Think back: In 1986, 1994 and 2012, tsunami warnings required the evacuation of all coastal areas identified in the Tsunami Evacuation Maps. Although the warnings were issued approximately three hours prior to anticipated arrival of the first tsunami waves, in all cases the roadways were in total gridlock with thousands of people trying to evacuate by vehicle from Waikiki and elsewhere. Luckily, the tsunami waves did not result in much inundation, or the result could have been a horrific mass fatality event. Given the population, there just isn’t enough time to totally clear everyone in the evacuation zone horizontally to high ground.

Considering this potential disaster, the Honolulu Department of Emergency Management (DEM) wisely includes the option of vertical evacuation into existing taller buildings. During the March 11, 2011, Great East Japan Earthquake and Tohoku Tsunami, vertical evacuation proved extremely effective in Japan. With only 30 to 60 minutes warning, tens of thousands of people survived by seeking refuge in taller existing buildings.

We personally inspected many of these buildings. After the Tohoku Tsunami, there was a realization that Hawaii could expect a tsunami very much larger than any in the 100-plus year historical record. Therefore, DEM has retained the vertical evacuation option.

On March 11, 2016, a new chapter was added to the ASCE 7 (American Society of Civil Engineers) standard used in all U.S. building codes, providing scientifically based methods for designing buildings for tsunamis. These requirements are mandated for all essential and critical buildings in the Tsunami Design Zone (TDZ) and are recommended for adoption in the local code for the design of taller buildings as per the community’s evacuation plan.

Since the Honolulu City and County DEM relies on vertical evacuation in its tsunami evacuation plan, the ASCE 7-16 tsunami design provisions were adopted into the Honolulu building code on May 20, 2020, for all new buildings taller than 65 feet in the TDZ — but now the Department of Planning and Permitting (DPP) is trying to rescind that requirement.

At the City Council, Bill 65 is currently being considered that would adopt the 2018 International Building Code, which references ASCE 7-16 for tsunami design. This bill originally required tsunami design of buildings in the TDZ that were taller than 90 feet (equivalent to 10 stories). Unfortunately, after nearly a year of development of the detailed provisions, at the last minute on Jan. 10 the DPP suddenly removed this requirement in the current January 2024 draft of Bill 65 CD1 — so there would be no design for tsunami safety of high-rise buildings at all. Just leave it to luck instead of engineering?

What now? The City Council should step in and restore coordination among city departments by including tsunami design for taller buildings as included in the DEM evacuation plans. The City Council would be protecting the lives of more than 100,000 residents in the tsunami zone, while also reducing the city’s liability in future litigation. Or we may all be disappointed to hear that tired excuse, “We will investigate and make sure this never happens again.”

Ian N. Robertson, Ph.D., S.E., is a professor in the University of Hawaii’s Department of Civil, Environmental and Construction Engineering; structural engineer Gary Chock, S.E., F.SEI, is president of Martin, Chock & Carden, Inc.; both were the original technical authors of the Honolulu Building Code amendment to require tsunami-resistant design of new high-rise buildings.