BRACE AND BOLT

February 4, 2016

Scientists have predicted that the Bay Area has a nearly three-in-four chance of experiencing a potentially deadly earthquake in the next 30 years. The estimates in “Third Uniform California Earthquake Rupture Forecast” issued in 2015 show a 72 percent chance that a magnitude-6.7 or larger quake which is almost the size of the 1989 Loma Prieta will strike the Bay Area before the year 2044. The odds of a much larger magnitude-7 quake are 50-50. Cows need to take the prediction seriously.

As we understand it this California Residential Mitigation Program is a joint-exercise-of-powers entity formed by its members, the California Earthquake Authority, a public instrumentality of the State of California (CEA), and the Governor’s Office of Emergency Services, (Cal OES). CRMP is a legally separate entity from its members. This program offers an incentive payment of up to $3,000 to help the pay costs associated with retrofitting existing wood framed houses to lessen earthquake damage. It appears that registration is open through FEBRUARY 20TH. You can learn more about the Brace and Bolt program from here.

In order to enable COWs to participate, on January 12th, the COWncil introduced an ordinance to adopt Appendix A3 of the 2013 California Existing Building Code Seismic Strengthening of Cripple Walls and Sill Plate Anchorage of Light, Wood-Frame Residential Buildings. The draft ordinance which was adopted by COWncil on January 24th, removes section A304.2, Foundations, of Appendix Chapter A3 due to the Town’s expansive bedrock, soils and areas of Whiskey Hill Formation.

For those COWs unfamiliar with the Whiskey Hill formation, for more than 40 years, it has been recognized that buildings located in an area of San Mateo County near Woodside, Menlo Park, and Atherton, have been affected by unusual foundation movement with varying amounts of uplift, and to a lesser extent, lateral movement caused by volume change in “a complex and highly chaotic underlying geologic unit” know known as the Whiskey Hill formation. This formation contains a mixture of highly expansive claystone and sandstone bedrock which has caused both vertical and lateral movement to improvements constructed upon it. You can learn about Whiskey Hill from a report from the Michelucci & Associates Inc. engineering firm which studied it.

COW has written urging earthquake precautions a number of times over the years. See here, here
and a MooTube video of a town earthquake meeting here.

We are happy to see the Town enable participation in the Earthquake Brace & Bolt program and we urge those qualified properties to take advantage of the program.

Leave a Reply

Your email address will not be published. Required fields are marked *