Tsunami holds lessons
for isles

Two UH researchers find that
hibiscus and hala trees help
block destructive sea waves

What University of Hawaii-Manoa tsunami researchers are learning about the Dec. 26 Indian Ocean tsunami could one day help make hotels and other buildings in Hawaii safer.

Barbara Keating and Charles Helsley traveled to the Maldives Islands about six weeks after the tsunami. Their study was published in the online "Science of Tsunami Hazards" journal.

Among their observations: Pandanus (hala) trees and bushy plants like the hibiscus between buildings and the sea helped lessen the waves' impact.

"They do a really good job of catching rocks and slowing water," she said. Keating said the hibiscus and pandanus are less intrusive than mangrove, which can overrun a waterfront area.

Concrete walls and safety glass in lobbies also helped reduce injuries.

"In the Maldives, people talked about the glass breaking in resorts and hotels as tsunami waves came in," she said.

Keating is working with colleagues in Australia and is hoping to find funding for more research on protecting buildings from tsunamis.

"I wanted to go and study the tsunami impact there because if we were to have something similar happen here, the damage will be of a similar nature," Keating said. "I knew it was directly connected to us here in the Pacific."

Based on observations and interviews with eyewitnesses, Keating said the tsunami reached heights of about 12 feet -- on atolls just barely above sea level.

"Everybody who was on the island had to be able to swim to survive," she said.

Helsley said the people in the Maldives were poor to begin with and lost what little they had. Many are dependent on the tourism industry, and tourists have stopped coming because of the damage to hotels.

"In a way it was like what happened after Hurricane Iniki on Kauai, where basically the economic engine for the island stopped and it was years before it got started again," he said. "There wasn't a lot of loss of life, but it was a loss of a way of life."

Keating also traveled to Sri Lanka in June to work with the Sri Lankan government to improve their tsunami response. She is trying to set up a program to train Sri Lankan scientists in Hawaii on tsunamis and seismology.

The atolls of the Maldives Islands are similar to the Northwest Hawaiian Islands and other islands in the Pacific. Sri Lanka's geography is much like the main Hawaiian islands, she added.

During his visit in the Maldives, Helsley was looking for clues to past tsunamis.

Helsley noted that the tsunami did not leave much of geologic record on the islands. The event was more noticeable for the erosion it caused than for leaving deposits on land.

One way to tell if a tsunami has struck in the past might be to look at ocean sentiments for evidence of erosion, Helsley said. But, he said, further study needs to be done to see if erosion caused by a tsunami is different from erosion caused by a hurricane or other large storm.

Both scientists said the Indian Ocean tsunami should be a reminder that a tidal wave will strike again in Hawaii, and residents here should be prepared.

"A lot of people that live here now were not here at the time the last tsunami came. We have to have continuing education in Hawaii as to what do you do and do you have any kind of plan for safety," Helsley said.