What was billed as a historic occasion for the California High-Speed Rail Authority and its Bay Area partners ended on an awkward note Wednesday morning when the rail authority failed to get votes it needs to renew its vows with Caltrain and other agencies involved in building the controversial, $68 billion rail line.

The rail authority was scheduled to approve at its Wednesday meeting a new "memorandum of understanding" with the Peninsula Corridor Joint Powers Board (which oversees Caltrain) and seven other agencies -- the Metropolitan Transportation Commission, the San Francisco County Transportation Authority, the Santa Clara Valley Transportation Authority (VTA), the City of San Jose, the City and County of San Francisco, the San Mateo County Transportation Authority and the Transbay Join Powers Authority. The new document would supplant the rail authority's existing agreements and formally commit the agencies to build a "blended system" in which high-speed rail would share tracks with Caltrain along the Peninsula.

The proposed agreement had been the subject of months of negotiations between staff from the rail authority and other agencies, including Caltrain, and has received support from the area's Sacramento representatives, some of whom have been skeptical about high-speed rail in the past. Early in the Wednesday morning meeting, rail authority CEO Jeff Morales called the new agreement a "triumph of common sense and practicality," Board member James Hartnett called the new agreement a "historic landmark" and board Chair Dan Richard called it an "example of what the public wants and expects for us."

But the public will now have to hold its expectations for another month. Board Vice Chair Lynn Schenk, a longtime skeptic of the "blended" approach championed on the Peninsula, appeared to surprise her colleagues by playing the role of runaway bride and taking a stand against the new agreement. Since the nine-member board has three vacancies and because another board member, Michael Rossi, was out of town, Schenk's opposition effectively deprived the board from having the five votes it needs to ratify the new agreement.

Schenk, a former Congresswoman from San Diego and the board's senior member, said she would be voting her "conscience" in opposing the new agreement. While her colleagues, most of whom have been appointed in the past three years, have largely embraced the blended system first proposed by then-state Sen. Joe Simitian, D-Palo Alto, Assemblyman Rich Gordon, D-Menlo Park, and U.S. Rep. Anna Eshoo, D-Palo Alto, Schenk has not been swayed. She said Wednesday that she cannot support the electrification of Caltrain "at the expense of the ultimate goal of high-speed rail."

"I owe the people of California nothing else than voting my conscience," Schenk told her colleagues at the Wednesday meeting in Redwood City, to which she jokingly referred as the "lion's den." "I hope you all expect that this is not something that is reflective of the work you've done and your very legitimate goals here."

The board's discussion followed comments from various area business leaders and from Caltrain Executive Director Michael Scanlon, who all praised the new agreement, which among other things calls for electrification of the Caltrain corridor, a project that the agency has been pursuing for more than a decade.

Over the past three years, the rail authority's new board, led by Richard and Jim Hartnett, have largely embraced blended-system proposal and Caltrain's electrification a key carrot for the Peninsula, where the rail project has been facing enormous resistance and multiple lawsuits (the latest of these was dismissed last week).

Schenk, whose term extends back to the board's earlier and more rancorous days, has been more reluctant about letting Caltrain tap into high-speed rail funds. In May 2011, shortly after the "blended" system was unveiled by Peninsula makers, Schenk joined then-Chair Curt Pringle in blasting the proposal, saying she would hate to see "our precious high-speed-rail funds" diverted to local causes and used to "bail out any regional transportation system."

On Wednesday, Schenk said that while she "fully understands and supports" the goals of Caltrain electrification, she "cannot support it at the expense of the ultimate goal of high-speed rail."

Her comments came after her colleagues all praised the proposed memorandum of understanding. Morales said the agreement between the rail authority and the various agencies "leverages resources and demonstrates the sort of partnerships that we need to make this program a reality across the state." Hartnett, a former Redwood City mayor, said the new document is "a reflection of tremendous amount of work and debate that's gone on for years." Richard called it "an example where people came together to discharge their public duties to make sure we're delivering a seamless system and doing it through collaboration and cooperation."

"I think it's a very good day," Richard said, before Schenk made her comments.

Once Schenk made her position clear, Richard took the unusual step of asking Schenk for a "courtesy vote" in favor of the agreement, in recognition of the fact that Rossi is out of town and that the document would have passed had he been present. He also took a five-minute break to confer with Schenk and legal counsel. After that, he declared that the item would not be voted on but would be deferred to next month's meeting.

Meanwhile, Caltrain's board of directors is scheduled to approve the new memorandum at its meeting Thursday morning.