County voters passed a $30 million bond measure from the Millbrae School District on Tuesday night, while the San Bruno Park School District’s $40 million bond and the San Mateo Community College District’s $564 million bond were rejected.

All three bond measures were designed to pay for modernization and upgrades to existing facilities and technology. Many schools in the three districts are more than 50 years old.

Over the past dozen years, San Mateo County voters have approved a number of bond measures to help schools cope with declines in property taxes and state funding that may or may not revive.

Millbrae’s bonds will charge district property owners about $30 per $100,000 of assessed property value each year, and San Bruno’s would have done the same. The college district measure would have cost county property owners an estimated $12.92 per $100,000 in assessed property value.