Abstract
　An earthquake of large magnitude rocked the San Francisco Bay Area on October 17, 1989. The damage resulting from this earthquake included liquefaction and other soil failures, structural failure of buildings and widespread disruption of lifeline facilities in the epicentral region and in numerous places adjacent to the San Francisco Bay Area.
　Earthquake damage to water supply pipelines was investigated, and an overview of the damage done to water supply pipelines in certain cities in the epicentral region and in the San Francisco Bay Area is given. The damage done to pipelines is discussed in relation to the ground conditions.

Key words: earthquake damage water supply system, pipelines, liquefaction.

*Department of Civil Engineering, Kanazawa University