For example, Mountain View officials last year decided against a grade separation at the Castro Street rail crossing, figuring that money could be better spent on closing the street and rerouting traffic to Shoreline Boulevard. Meanwhile Palo Alto officials have heavily favored running Caltrain in a below-grade tunnel or trench with road crossings above.

For transit advocates and city officials, this was reportedly the first time they had heard VTA dictate specific standards for grade-separation projects, which they say could disrupt months of city planning.

Palo Alto and Mountain View city officials expressed alarm recently that VTA planners seemed to be setting a rigid template for eight projects from Sunnyvale to Palo Alto that would separate roadways from the railroad tracks. Those concerns centered on a brief outline buried in a staff report for a Friday, April 21, VTA board workshop. The excerpt noted that to receive funding, rail-crossing projects "would maintain the tracks at grade level with traffic and pedestrian access either over or under the tracks."

As the Santa Clara Valley Transportation Authority prepares to dole out the first portion of the $6 billion Measure B funds, Midpeninsula cities are raising concerns that the agency could be putting onerous restrictions on projects for Caltrain grade separations.

Midpeninsula cities have had a complicated relationship with VTA, especially last year as the transit agency asked for support from regional political leaders for its sales-tax initiative. The request stirred up grievances among north county and west valley leaders because they felt VTA had spent the bulk of past tax measures on projects benefiting San Jose, particularly construction of a long-sought BART connection to the city. They ended up supporting the measure after VTA officials pledged to cap BART spending at 25 percent.

"Staff was directed by the board to be flexible where the grade-separation project funding is concerned and to work closely with the cities to come up with alternative language in the proposal," wrote VTA spokeswoman Stacey Hendler Ross in an email to the Mountain View Voice. "There will be at least four more opportunities for public review of the proposal before it goes to the board for a June vote."

At the meeting, VTA officials appeared somewhat surprised by the uproar. Scott Haywood, a project manager, emphasized that the VTA would take the cities' concerns into consideration before the agency's full board meeting in June to approve the final budget for the initial round of sales tax money.

Those concerns were echoed by several speakers on Friday morning at a VTA board meeting to discuss allocating just under $300 million next year for the first phase of the new transportation sales tax. This initial allotment includes just $7 million in grants for early grade-separation planning, but a total of $700 million is planned for these projects over the 30-year lifespan for the sales tax.

"Does this mean (Mountain View's plans) wouldn't get funding even though they would be less expensive?" she said. "I think VTA has a reasonable intent, but this particular policy is not the right way to go."

Multiple Midpeninsula cities are pursuing grade-separation projects in tandem to prepare as Caltrain upgrades its system for faster and more frequent service. The train agency is currently working to phase out its older diesel-engine trains for a faster electrified system. Caltrain officials are also planning to eventually use the train corridor for the statewide high-speed rail line.

In any case, the $700 million earmarked for grade separations is already expected to be inadequate to pay for all eight Caltrain crossings from Sunnyvale to Palo Alto. VTA staff note that the difference will need to be paid by "outside funding sources" -- in other words, the cities along the Caltrain line.

"The VTA staff proposal to only consider designs with tracks at ground level restricts proper alternatives analysis," he wrote in an email. "This may not result in the most cost-effective design and may not best meet the broader set of design issues that are critical to the communities."

Concern rises over restrictions for grade separations

VTA report spells out that rail line would be kept at grade level; roadways to run over or under