The golden shovels have been waiting to break ground for a long time; Caltrain's electrification project has been decades in the making.
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The $2 billion program was finally able to secure federal, state, and local funding.
This will push the 153-year-old rail line into the 21st century by converting the diesel service we all know into high-performance electric trains.
"Our country is great when we can come together and build for the future. That's what we're doing right here on the Peninsula," said Governor Jerry Brown.
Brown and other politicians marked the history-making milestone at the Millbrae station.
"It's about convenience," said Rep. Nancy Pelosi, D-San Francisco. "It's about quality of life for families so people don't have to spend all that time in their cars."
"Get rid of the diesel, get rid of the pollution, get rid of the slow and ineffectiveness of it to a 21st century system that's going to carry more than double the capacity," said Rep. Anna Eshoo, D-Palo Alto.
The modern trains will be faster, run more often, and carry more passengers. Right now, 65,000 people ride Caltrain each day.
The project should be complete in 2021.
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