Caldecott Tunnel

December 19, 2016, 5am PST
Before the ballot measure would go to voters, state legislation needs to be written, passed, and signed by Gov. Brown. The first step was taken Dec. 14, when the region's planning agency discussed the option. Tolls are $5, last raised $1 in 2010.
SF Gate
September 13, 2012, 1pm PDT
Scientists have created <em>sounds</em> from air pollution data that allow listeners to hear the striking differences and similarities between the air we breathe in America's most polluted city and remote pine forests.
The Atlantic