• Extending BART via Del Norte north along Interstate 80 likely would mean diverting either the Fremont-Richmond or San Francisco/Millbrae-Richmond line at Del Norte, thus bypassing Richmond.
    Extending BART via Richmond, however, would add five minutes to the commute north to Hercules by comparison to the El Cerrito Del Norte alignment, according to a West Contra Costa High-Capacity Transit Study presentation to WCCTAC at its May 27 meeting.
    The respective costs of the two BART options, according to that study, differ by only about half a percent: $2.453 billion for Richmond, and $2.465 billion for Del Norte.
    The Richmond alignment would run along Rumrill Boulevard and via Contra Costa College and Richmond Hilltop to Pinole and Hercules.
    The Del Norte alignment would run along I-80, with likely stops at San Pablo Dam Road and Hilltop on the way to Pinole and Hercules.
    In April 2013, shortly after Mallett first floated the idea of a BART extension via Del Norte, some Richmond officials expressed concern that it would marginalize the Richmond station, which is paired with an Amtrak Capitol Corridor station.
    And some Hercules officials said their city's long-envisioned and yet-to-be-built Intermodal Transit Center with an Amtrak stop and a ferry terminal along San Pablo Bay would be a better solution to I-80 congestion.
    The idea of extending BART to Hercules was discussed in the 1980s and 1990s, with some officials arguing over Richmond versus Del Norte routing, while others questioned whether communities to the north even wanted to be hooked up to BART at all.
    Since those days, BART has extended service to Pittsburg/Bay Point, Dublin/Pleasanton and Millbrae/San Francisco International Airport, and is currently building an extension to San Jose and eBART to Antioch. BART also inaugurated monorail service to Oakland International Airport in 2014.
    Mallett on Friday said the high-capacity study shows that "a BART extension in West County is sorely needed," and added: "This will enable BART to subsequently do an alternatives analysis that could lead to an optimal BART extension in West County."
    Contact Tom Lochner at 510-262-2760. Follow him at Twitter.com/tomlochner.