Kwajalein Atoll responds in wake of tsunami warning
April 4, 2011
KWAJALEIN Atoll -- As a tsunami radiated from the epicenter of the March 11 earthquake that struck Japan, decisions were being made on Kwajalein about local repercussions, their severity and possible courses of action. The earthquake was the most severe ever to be recorded in Japan.
The meteorologists at Kwajalein Weather Station relayed word of a tsunami warning to Col. Joseph Gaines, commander, U.S. Army Kwajalein and Atoll, his staff, and an emergency operations center was activated at the command headquarters around 8:30 p.m. After weighing predicted wave size, direction and speed, Gaines was advised to have the communities of Kwajalein and Roi-Namur take shelter in the upper levels of buildings and residences.
The temblor that shook Japan with a magnitude 9.0 ultimately moved that island 8 feet. The underground shaking resulted in deep ocean disturbance and unleashed a 24-foot tsunami that radiated from the quake's epicenter, according to Mark Bradford, chief meteorologist for Kwajalein Weather Station.
As the wave raced through the Pacific Ocean at speeds in excess of 500 miles per hour, its energy and size were dissipated by friction, gravity and land masses. By the time the tsunami reached Kwajalein Atoll, increased wave action was adding 1.3 feet to normal ocean waves, according to Bradford.
USAKA's Emergency Management officer Maj. Stephen Parrish and deputy to the commander, Joseph Moscone, coordinated the information coming in from USAKA, Kwajalein Weather Station, Kwajalein Police Department and Kwajalein Range Services so Gaines could focus on the data he needed to make a decision about evacuation.
"I thought (the team) was phenomenal. Everybody pulled together. ... People had excellent input into the decision-making process and people had a pretty good understanding of the plan," said Parrish.
The residents of Roi-Namur were given the "shelter-in-place" order first. The wave was headed toward the atoll from the northwest and would hit that island initially. Chief of Police Bradley Walker and the Roi-Namur Police Detachment made the announcement to residents.
After reviewing the data coming in from other locations in the Pacific and Kwajalein Weather Station, Gaines decided residents of Kwajalein should also evacuate to designated locations or two-story houses. The safety of residents was the primary concern, according to Gaines.
"The earthquake in Japan was unprecedented in history. Without more conclusive data from locations to our west and north, I had to make a call and that call was to have residents move to shelter locations and be prepared for the worst. Thankfully, it didn't come to that. But ultimately, the well-being of our people took top priority," he said.
Once Gaines gave the order, an announcement was broadcast on the AFN Roller Channel and a 3-minute siren warble blast signifying evacuation to shelters.
Behind the scenes, USAKA's director of Public Works Todd Dirmeyer and director of Logistics Michael Quigley, along with their KRS counterparts, were taking steps to ensure some of the island's more vital assets would remain secure. This included preparations to shut down the power plant, if necessary, and sending larger vessels docked at Kwajalein, such as the Great Bridge and the tug Mystic, "out to sea in order to minimize damage to the pier," according to Quigley. During a post-event meeting, Dirmeyer and Quigley commended the efforts of KRS staff in executing these preparations on short notice.
Because the wave hit Roi-Namur and Kwajalein during low tide, ocean levels were lower and few effects were noticed. An ebbing tide brought water levels down to 1.7 feet, negating much of the tsunami's impact. However, a tsunami definitely passed through Kwajalein Atoll.
"The tsunami continued to raise and lower water levels in the lagoon and ocean, even after there was no threat to the islands. The ocean and lagoon are still, five days later, showing the effects of aftershocks and pan-Pacific sloshing cause by this incredible energy release," said Bradford in an e-mail Wednesday.
The story could have been different had the ocean been under high tide conditions when the wave hit. The additional water combined with high tide could have resulted in more than a foot of water rushing the islands of Kwajalein Atoll, speculated Bradford. Despite the combination of low tide and wave dissipation, there were reports of receding water, which preceded the wave, and left private boats on Roi-Namur sitting on sand bars in the lagoon there.
After receiving the tsunami warning, Continental Airlines received word from Majuro that the airfield there was closed. Continental then flew directly from Kwajalein to Honolulu. Passengers ticketed for Majuro were directed to deplane on Kwajalein and were housed in the Religious Education Building and hosted by the Kwajalein community at-large.
"At approximately 11:47 p. m., the water level in the marina dropped four to five feet in about five minutes. The reef was exposed inside the marina approximately one foot," said Roi-Namur Police Officer Gary Blythe, in a report after the event.
Another consequence of the earthquake was a break in communication lines exiting Kwajalein. Residents who wanted to call back to the States found they could not get an outbound phone line. This was frustrating especially for those who wanted to assure their families they were safe. Incoming long-distance calls were possible and Hobby Shop manager Denise Dorn said she was on the phone on and off for hours after news of the temblor and tsunami reached her family and friends stateside.
Gaines thanked the community for its support and cooperation during these events and said he's already looking at the way forward. He discussed what went right with the emergency plan and possible improvements, including the best ways to communicate with residents and how pets fit into an evacuation scenario, among many others.