San Mateo County supervisors oppose Caltrain tax measure proposed by supervisors in San Francisco

File Photo. Caltrain Locomotive 918 heads south in San Mateo County. Photo Copyright: Duncan Sinfield/KTVU. (Duncan Sinfield/KTVU)

A sales tax proposed on Tuesday by San Francisco's Board of Supervisors to support Caltrain, which would be assessed in all three counties the commuter rail serves, drew immediate criticism from San Mateo County supervisors. 

San Mateo officials, who are promoting instead what they are calling a "clean" ballot measure, said the San Francisco proposal would impose too many conditions on the release of funding. 

"The San Francisco Board of Supervisors approved an alternative sales tax measure that is illegal, unwinnable at the polls, and unworkable for Caltrain," San Mateo County Supervisor Dave Pine said in a statement on Tuesday. "Unless amended, this poison pill means the Caltrain sales tax is now dead, which puts the railroad in great peril." 

The measure would impose a 0.125 percent (one-eighth percent) sales tax and would appear on the November ballot in San Mateo, Santa Clara and San Francisco counties. 

RELATED: Santa Clara County defers Caltrain tax measure, transit agency at risk of temporary shut down

Before reaching the ballot, however, the measure must be approved by each county's board of supervisors, each county's transit agency, and the Peninsula Corridor Joint Powers Boards, known as the JPB, which oversees Caltrain. The JPB is made up of representatives from each of the three counties. 

The measure would provide Caltrain with dedicated funding; it now depends on passenger fares and contributions from member agencies. But the funds would be withheld unless the JPB meets several conditions, including changing its governance. 

One condition is that there be an independent special counsel and auditor for the JPB, separate from the lawyer and auditor of the San Mateo County Transit District, known as SamTrans, which is responsible for running Caltrain day to day. 

Another condition is that the tax revenue be held in an escrow account under the control of the JPB until its governance structure changes. 

"In essence the Joint Powers Board is a paper board," San Francisco Supervisor Aaron Peskin said at Tuesday's meeting. "Yes, I'm saying it. No, this is not a power grab (by San Francisco)." 

Peskin said, "It is time to extract Caltrain from SamTrans and their intermingling of responsibilities and potentially funding." 

If the JPB doesn't makes changes in time, or Caltrain does not receive enough federal funding, the measure proposed in San Francisco provides for up to $40 million to be released. But the full release of funds depends on the JPB meeting the conditions, and San Mateo officials worry that this will jeopardize Caltrain's future. 

Warren Slocum, president of San Mateo County's Board of Supervisors, tweeted on Tuesday that the ballot measure was "legally flawed" and would put "thousands of Caltrain passengers in great peril."