The Los Angeles County Board of Supervisors on Tuesday unanimously approved a motion seeking more information on the scope and costs of a tsunami siren warning system for coastal communities, including Marina del Rey.

The motion co-sponsored by Supervisors Don Knabe, whose district includes the marina, and Zev Yaroslavsky seeks feedback from experts on siren systems to determine the cost of implementing and maintaining a siren warning system. It also asked for cost comparisons for installing a siren system in either unincorporated coastal areas of the county or deploying it along the entire county coastline.

The board in March voted unanimously for a report on the feasibility of a tsunami siren warning system in the wake of the deadly tsunami that ravaged Japan. The report by the county's Office of Emergency Management was returned May 18 to the board and was based on the findings of a working group that included the county's emergency office, the Los Angeles County Sheriff's Department, the county's Department of Beaches and Harbors, the Los Angeles County Fire Department and the Department of Public Works.

The working group found that the California Emergency Management Agency has been conducting a survey of state coastal areas and the use of siren warning systems. It also analyzed conventional siren operations, siren activation, and the findings of a mass notification siren warning system test conducted by the sheriff's department in 2007 in Marina del Rey.

Knabe and Yaroslavsky's motion asked the Office of Emergency Management to proceed with the evaluation by the siren experts after CalEMA completes its survey. The motion also asked for the identification of possible funding sources.

Japan was struck March 11 by an 8.9-magnitude earthquake that generated a tsunami with waves reaching 40 feet high that rolled into populated coastal areas, killing thousands and creating a nuclear crisis.