At tomorrow’s San Francisco Board of Supervisors meeting, the board will consider a fast-moving process to decide on a spending package for a November transportation ballot measure.

The expenditure plan could include investments in BART, Muni, Caltrain, as well as bicycle and pedestrian safety, build on earlier work by the Mayor’s 2030 transportation task force in 2013, which outlined transportation needs and priorities. The measure would run for 25 years, raising about $100M annually; about $2.5 billion in current dollars.

The action being proposed for tomorrow is a process with 3 public meetings in May and June to discuss priorities for the ballot measure.

For Caltrain supporters, an important question is whether San Francisco would use this measure to match Santa Clara County’s planned contribution of $300Million for improvements that would increase capacity, reliability and speed (longer platforms, longer trains, level boarding) after basic electrification. Extra capacity provided by electric service is expected to quickly be filled with ridership growth. The corresponding cost in San Francisco would also be about $300 million, according to Caltrain. Other Caltrain investments San Francisco could choose include grade separations and committing San Francisco’s share of system reliability investments.

We don’t yet have information about other potential investments for the measure for Muni, BART, and active transportation.