Updates to tsunami zone maps result of more accurate data

The Maui County Civil Defense Agency has updated tsunami evacuation zone maps – with major changes in the Kahului area and the addition of new maps for two areas on Maui.

Published in The Maui News on June 30, the six-page layout highlighted evacuation zones across Maui, Molokai and Lanai. The zones, which are activated during a tsunami warning, were last updated in 2006.

“The need (for the update) was that there is better scientific modeling available,” said Anna Foust, county emergency management officer. “We used the data to ensure that we have the most accurate information.”

In a statewide initiative, scientists and geophysicists from the University of Hawaii-Manoa created a formula that utilized typography data from each island to help define evacuation zones. The two-dimensional model evaluated 196 miles of Maui coastline, along with historical and hypothetical tsunami data.

“This has been a long ongoing process, and I’m glad we finalized it,” Foust said of the new maps that took about two years to complete.

The Kahului area, from Waihee to Kanaha Beach Park, experienced the largest evacuation zone growth of the 24 maps provided by the agency. The evacuation area – marked as a shaded area on the maps – was extended from East Wakea Avenue and Keolani Place all the way to Walmart on Hookele Street. The zone includes University of Hawaii Maui College and is bordered by South Wakea Avenue and Moali, Kauai and Kuula streets.

“I was surprised a little bit,” Foust said of the new zone. “But that was from not seeing the modeling and assuming the water would be going into (Kahului Harbor). If you look to the east, there’s Kanaha Pond, so the water is coming in all the way past the wetlands area.”

Other notable changes included the Kihei area – from Kamaole Beach Park III to Kealia – which saw evacuation zone growth from South Kihei Road to Liloa Drive. Molokai had multiple extensions along Kamehameha V Highway, which includes the Mitchell Pauole Community Center on Kolapa Place.

Aside from minor evacuation zone growth to all areas of the county, the agency also added two area maps – Keanae Village, with most of the East Maui peninsula in the evacuation zone, and Awalau Gulch to Kahakuloa Head.

“Using the models, we were able to draw evacuation maps for Keanae and Kahakuloa – which there was no data for,” Foust said.

Previous evacuation zone determination used one-dimensional modeling that had little data from which to extrapolate, Foust said.

“Before, it was historical measurement points that marked previous tsunami evacuation zones and how far the water went up,” she said. “But these (newer) models looked at other things and validated it with past models and historical data.

“When we’re doing these evacuation maps, that doesn’t mean how far the water will go but shows how far it could go. . . . We add a little buffer because Mother Nature does not recognize our lines drawn on a map.”

In response to whether the changes will affect residents financially, including their insurance policies, Foust said the maps are strictly for county evacuation purposes. She said the Federal Emergency Management Agency’s Flood Insurance Rate Map defines its own hazard areas and risk premium zones.

With many residents and businesses now in the evacuation area, Foust is urging residents to not be “complacent” and to be “prepared for anything.”

“We tell folks to get in and up,” she said. “If you have family outside the zone, we recommend them to go there first. We also say if you’re not in the evacuation zone to stay put. We need to make sure we keep the roads clear for people trying to get out of harm’s way.”

Foust said that there are three things people should do in the event of a tsunami: be informed, make a plan and make an emergency kit. She also said residents should listen to the radio for announcements on assembly areas, if they have no place to stay.

“Preparedness will be applicable to anyone, with or without notice,” she said.

The agency is planning to host community meetings in each Maui district to answer questions and to explain changes to the evacuation map.

* Chris Sugidono can be reached at csugidono@mauinews.com.