Muir Beach Tsunami Study

Some Muir Beach residents, along with coastal dwellers in Stinson Beach, Bolinas and Dillon Beach, are dangerously uninformed about the possibility of a devastating tsunami hitting the community, according to a recently completed study by researchers from Dominican University in San Rafael.

One out of four coastal residents is unaware of the area’s previous history of tsunamis, and a startling ten per cent believe the best thing to do in the event of a tsunami warning is to scan the ocean for sea waves, a reaction that could be fatal.

The study, conducted by Dr. Matthew Davis and the Marin County Office of Emergency Services, is based on a survey conducted by mail last spring. Responses were obtained from 166 residents of coastal communities in Marin, including 16 who live in Muir Beach.

There was good news from the study, however, according to Marin County Emergency Services Coordinator Bruce Stahley. “A lot of citizens understand the threat of a tsunami and are anxious for more information on how to deal with it,” Stahley said.

Nearly half of the respondents didn’t know they should go rapidly inland to protect themselves in the event of a tsunami warning and more than a third indicated they had no idea how much time they’d have to react before a giant wave arrived. Depending on the location of the tsunami-generating event, a wave traveling at a speed of 500-700 miles per hour could arrive in a few minutes or take several several hours to get here.

A tsunami, according to government scientists, is a sea wave generated by an offshore earthquake, landslide, volcanic eruption or even a large meteor landing in the ocean. While infrequent in California, tsunamis can and do occur. Guests and staff of the Pelican Inn were evacuated to the overlook June 16, 2005 when a tsunami warning was issued following an Alaskan earthquake. In 1946, a magnitude 7.4 earthquake in the Aleutians generated a 13.5 foot wave at Muir Beach. The 1964 Alaskan earthquake resulted in a 20-foot wave at Crescent City that killed 11 people.

Seismic experts at UC Berkeley say Marin’s coast could be subjected to tsunamis of devastating force. The Cascadia Subduction Zone, stretching from Cape Mendocino to Puget Sound, is believed to be capable of an earthquake as large as 9.0. An earthquake of that force could produce a tsunami as large as the one that hit Southeast Asia in 2005.

The Marin OES study indicated that Muir Beach residents had received more information about tsunami danger than their neighbors in Stinson Beach, Bolinas and Dillon Beach. They rated local government better prepared to deal with a tsunami emergency than state or federal agencies.

While 88 per cent of Muir Beach residents who responded indicated they had food and water to survive for three days, only 44 per cent said they had discussed emergency preparedness plans with friends and neighbors.

The Muir Beach Area Disaster Council is currently focusing on assisting every resident in collecting necessary emergency supplies, including food, water, first aid, blankets, lights, medications, and more. Lists are available at muirbeachfire.com. Emergency medical training is planned for community members this coming January.

County OES officials plan to have a public meeting in late January to brief coastal community residents on the survey and to discuss changes in their response plan in the event of a devastating tsunami.

Back to the top