San Francisco's pension time bomb just exploded, with the city being told it will have to pony up $20 million more than previously expected in the next fiscal year.

That will bring the total bill for city government retirees to about $375 million - $100 million more than this year, according to the city Controller's Office.

To give that some perspective, $375 million is more than three times the annual budget for the Recreation and Park Department.

A big chunk of the increase is the result of a mandatory, 3.5 percent cost-of-living hike for retirees required under terms set out in the City Charter.

About $60 million of the $100 million will have to be paid for out of the general fund, the source of the money for most city departments.

"Compound the pension payout with the overall economic downturn, and there will absolutely be a reduction in city services," said Supervisor Sean Elsbernd.

Worse yet, the following fiscal year, the city's estimated pension payout is expected to grow to $439 million - or about what it costs to run the Police Department for a year.

And the year after that? The city is looking at a $532 million payout.

Public Defender Jeff Adachi, who floated an unsuccessful ballot measure in November that would have required city workers to pay more into their pensions and health care plans, said even the new numbers don't include the $63 million a year the city kicks in for the estimated 10,000 workers who don't pay anything into their pensions.

Most city politicos and all labor leaders adamantly opposed Adachi's measure, calling the health care hikes unfair. They also took aim at a civil grand jury report that sounded the alarm on the pension problem, insisting that the estimates of the coming increases were out of line.

They were right on one point.

The grand jury's estimates for this year were off - they were under.

China connection: Even before Chinese President Hu Jintao landed in Washington for a visit with President Obama, a Chinese delegation toured the Central Valley over the weekend with an eye toward competing to develop the state's high-speed rail line.

Representatives from China's Ministry of Railways and China Railway Construction Corp. visited Fresno with Assemblywoman Fiona Ma, D-San Francisco, one of the $43 billion project's strongest advocates in the Legislature.

Also in the group was Jeffrey Chang, a San Francisco lawyer working for Prometheus Investment Group, which is hoping to partner up with the Chinese on the high-speed rail deal.

The company's co-founder is Alexis Wong, a San Francisco housing developer who spends most of her time these days in Hong Kong and Beijing.

Wong also happens to be a longtime supporter and close friend of Ma.

Ma insists she isn't playing favorites in the rail competition, and expects at least four teams - representing France, Germany, Japan and China - to be in the running when the bid process gets going in earnest later this year.

"I am not involved in any way with the High-Speed Rail Authority's contracting proposals," Ma said. "I'm just like a PR spokesperson to keep high-speed rail on track."

Her push for the rail line is one reason Ma will be in Washington today at a State Department luncheon for China's president, hosted by Secretary of State Hillary Rodham Clinton and Vice President Joe Biden.

Party time: Looks like both the Chinese Chamber of Commerce and downtown Chamber of Commerce are pitching in to cover the estimated $40,000 to $50,000 tab for Mayor Ed Lee's inaugural reception at City Hall.

Chinese chamber boss Rose Pak said she had asked execs at the downtown chamber if they could come up with $30,000 or so. Her group plans to cover the balance once the final bills roll in.

Downtown chamber President Steve Falk said his group wasn't a contributor to Lee's Jan. 11 inaugural. Any checks the chamber raised from businesses are being handed over to the city nonprofit fund that pays for special events, he said.

"I don't know what the final total was," Falk said. "But the obvious goal was to minimize any cost to the city."

Word of the two chambers' inaugural largesse came as a group calling itself San Franciscans for Clean Government issued a report Tuesday showing that two Pak-affiliated organizations - the Chinese Chamber and Chinese New Year Festival Committee - spent $19,506 in 2009 to fly Board of Supervisors President David Chiuand Supervisors Carmen Chu and Eric Mar to China.

That made up half the total that outside interests spent on supervisors' travel in the past two years.

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