SAN FRANCISCO (CBS SF) – Voters in San Francisco, Alameda and Contra Costa counties voted Tuesday to pass Measure RR, a $3.5 billion regional bond measure to help improve BART’s transit infrastructure.

The measure required a two-thirds majority to pass. San Francisco voters passed it with 81.1 percent of the vote, and Alameda County voters passed it with 70.8 percent. Only 59.5 percent of Contra Costa County voters approved the measure, but voters throughout the three counties passed the measure with 70.1 percent.

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Infrastructure to be improved includes 90 miles of severely worn tracks, water-damaged tunnels and 44-year-old train control systems, among other projects.

BART officials have said the bond measure was necessary to upgrade the system, which has many components still in place from its construction in the 1970s.

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Opponents of the measure have said the agency hasn’t made reinvestment in the infrastructure a priority, instead focusing on expansion to the South Bay and elsewhere.

Roughly two-thirds of BART’s capital budget is now devoted to system improvements rather than expansion.

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