The chief administrator of California's high-speed rail project, who endured withering criticism of the project under his watch, announced his resignation Thursday.

Roelof van Ark's departure comes as Gov. Jerry Brown, exerting increasing influence over the project, prepares to try to push it through the Legislature this year.

Lawmakers are highly skeptical of the project, and van Ark's relationship with many of them had soured.

Minutes after van Ark's announcement at a California High-Speed Rail Authority board meeting in Los Angeles, board Chairman Tom Umberg said he, too, will step down.

Umberg, whose decision followed talks with Brown's office, will remain on the board but yield the chairmanship to Dan Richard, a Brown adviser appointed to the rail board last year by the Democratic governor.

The changes were widely seen as a bid by Brown to recast the rail authority before legislative hearings start on the $98.5 billion project.

"Clearly there's an effort under way to begin anew," said state Sen. Joe Simitian, D–Palo Alto. "I think the question is, 'Is it too little, too late?' And I think the answer to the question is, 'We'll see.' "

Van Ark, 60, cited personal reasons for his resignation, effective in two months. The administration characterized it as a mutual decision.

"There was common agreement that this was a good time for a transition," Brown spokesman Gil Duran said.

Duran added that Richard and Mike Rossi, another adviser Brown appointed last year to the rail board, were chosen "to kind of lead the way."

The rail project's opponents in the Legislature seized on van Ark's resignation, calling it evidence of the authority's dysfunction.

"There's no confidence in anything they do," said Sen. Doug LaMalfa, R-Richvale. "He's either been forced out, or he's just tired of fighting the fight."

Hired in 2010, van Ark oversaw the drafting of an updated business plan that more than doubled the project's estimated cost over 20 years.

Some lawmakers praised the plan as a more credible document than before, but its release was followed by a series of setbacks. They included a Field Poll showing huge public opposition and a report in which the project's peer-review group told lawmakers its financing plan was so uncertain it could not recommend funding construction.

Sen. Alan Lowenthal, the Long Beach Democrat who chairs the Senate Select Committee on High-Speed Rail, said "there wasn't a great match" between van Ark's technical skills and ones that might have benefited him in the Legislature, such as an aptitude for building "relationships … promoting it."

Lowenthal said of van Ark's resignation, "Hopefully, it will signal a new beginning."

Van Ark's move comes at a critical point for the project, with organizers planning to start construction in the Central Valley this fall.

Van Ark used his announcement to reiterate support for the rail authority's plan to start construction in the Valley, controversial because it is far from California's population centers.

In their comments Thursday, Brown administration officials signaled staying the course.

While Richard said he was "very skeptical" of starting construction in the Central Valley when he joined the board, he said, "I sit here today as somebody who's been fully convinced."

Brown became a vocal supporter of the project last year. This month, Brown proposed folding the authority into a new state agency, a measure rail officials support. He also has another vacant position on the board to fill.

"I think that the governor is going to put his stamp on it, and put his kind of people in," Lowenthal said. "Whether he wanted to or not, this is going to become a high priority for him."

In his address to rail board members Thursday, van Ark said, "I need to focus myself more on my family, and maybe some other interests."

He said he might stay on as a consultant.

It was only late last year that van Ark told The Bee he considered it a personal challenge to ensure implementation of the project.

"I really believe that California should have a system like this," van Ark said at the time. "This state is so well positioned for high-speed rail."

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Call David Siders, Bee Capitol Bureau, (916) 321-1215. Follow him on Twitter @davidsiders.

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