HUNTINGTON BEACH – The city's tsunami evacuation map is being revised to make it easier to follow.
The city has nearly 70,000 residents living in tsunami inundation zones, with beach crowds of up to 100,000 on busy days.
The evacuation map hasn't been updated since 2005, said Brevyn Mettler, emergency services coordinator of the Huntington Beach Fire Department.
"Huntington Beach has always been on the forefront of tsunamis in California," Mettler said. "We have one of the largest amounts of residents that would have to be evacuated for the worst-case scenario."
A tsunami typically is caused by an earthquake, which triggers a series of large and destructive waves. According to the city's Emergency Management and Homeland Security's tsunami emergency information, if a tsunami hits the Orange County coast, waves could reach as high as 32 feet, sweeping debris such as boats and heavy rocks inland.
"The (earthquake) fault lines are typically what generates a tsunami," said Eric Engberg, chief of operations for the Huntington Beach Fire Department. "Usually what happens is that a quake will occur along a fault line – sometimes they slip up and down and sometimes they slip sideways – but that slipping of the fault lines can also displace the water, and then the water starts to be pushed out. Those waves radiate out like long flow lines and can travel up to about 500 miles per hour as they run down the coast."
Rick Wilson, senior engineer geologist with California Geological Survey, is a tsunami expert for the state Department of Conservation. Wilson said the north coast of California is the most hazardous area for potential tsunami destruction, but Southern California can be susceptible to severe danger too.
"With the Huntington Beach area and a lot of Orange County, it's very low lying and almost below sea level, so even a 10-foot surge could travel a mile or so inland," Wilson said.
Claudine Jaenichen, a Chapman University professor and lead researcher of "Wayfinding for Disaster Planning," presented a case study on the importance of the design of evacuation information, in New Orleans in February at the National Evacuation Conference.
Jaenichen's study aimed to evaluate the content of evacuation materials and how much residents could recall.
She found through a study she conducted in Santa Barbara this summer that visual items, such as maps, were most easily remembered.
The original evacuation map provided by Santa Barbara failed 100 percent in each test, and was then eliminated from the study. With clearer instructions and redesign, Jaenichen's study showed that visual instructions provided the subjects with the most stable recall after 24 hours of being tested. These findings were presented at the California State Emergency Management Conference in October, gaining further recognition.
The Orange County Sheriff's Department, which coordinates emergency plans with all cities countywide, met with Jaenichen and decided that Huntington Beach would be the best pilot city in the county.
"A picture can go a lot further than words. A lot of our maps in public service don't have landmarks, per se. ... They'll have the street names (and) map grids. But for the everyday person, they're not using that, ... they're using their navigation systems instead," said Donna Boston, Orange County emergency manager. "The maps need to be visually (understandable)."
The redesign involves different evacuation options and routes, simplified information, labels and arrows, and testing the materials to see how comfortable residents feel with the maps.
"The tests and study have proven that visual communication is more retainable," Jaenichen said. "Map reading takes a certain skill. ... This is situational design – the information is meant to be recalled during the specific time of crisis. The most important thing in approaching the visual campaign is reducing the information and making it straight and to the point."
Mettler and Jaenichen said they hope to start implementing the study in Huntington Beach by mid-November. Mettler said he likes Jaenichen's ideas to better convey the mapping instructions to the public.
"That's something we've always struggled with, is how to do we get the message to the people," Mettler said. "It's hard to convey to the public that the current inundation maps by the state are the worst-case scenario. They're not a guarantee of where the tsunami's going to take place, and they're also difficult to read," Mettler said.
Engberg said the city's current evacuation map would make sense to people familiar with the area, but not necessarily to visitors. Engberg said it could be a good idea to distribute information to hotels so tourists and visitors are better prepared for evacuation if a tsunami were to strike.
"We could work through the Chamber of Commerce to help distribute information out to businesses and hotels," Engberg said. "What we're really trying to do is provide safety and protection to the public and that includes the people that live here, but also the tourists who come visit."
Boston said she's excited about Jaenichen's passion for emergency management and if the pilot in Huntington Beach goes well, she hopes to implement it other cities in the county.
"I've been in emergency planning for a long, long time and it's hard to get people's attention because there's so much on their minds," Boston said. "We try to get time in everybody's brain to think about being prepared, and if (Jaenichen) is going to help us do that, we're all for it. We need to take advantage of any force-multiplier to help us carry that message – anything that makes it easier for our community to prepare, that meets our mission."