SAN MATEO COUNTY (CBS SF) — Repair work has begun on eight sirens posted along the San Mateo County coast that are designed to alert residents in the event of a tsunami, a sheriff’s spokeswoman said Tuesday.

During a routine test of the tsunami warning system last Wednesday, only three of the eight sirens along 30 miles of coastline between Pacifica and Pescadero functioned properly, San Mateo County Sheriff spokeswoman Rebecca Rosenblatt said.

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Crews started preparing the sirens for replacement on Monday, she said. The repair project is expected to be completed by Sept. 4, when another test of the warning system is scheduled.

While the sirens are out of service, the county Office of Emergency Services has developed a set of procedures to ensure that the public will be notified if a tsunami occurs, Rosenblatt said.

Police and sheriff’s deputies are prepared to fan out through low-lying coastal areas to warn residents of any tsunami danger should the need arise, she said.

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Notifications would also be sent out via email and text message using the county’s emergency alert system, SMC Alert.

Anyone can sign up for SMC Alert online at

Rosenblatt said the sheriff’s office will inform the community as soon as the sirens are back in service and functioning properly.

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