The unveiling of Stanford's billion-dollar hospital expansion plan caused both excitement and worry among Palo Alto City Council members Monday night.

The 20-year plan includes expanding Lucile Packard Children's Hospital by a third; building a new, 600-bed, earthquake-safe Stanford Hospital; and replacing several medical school and office buildings by 2025.

The expansion would add 1.3 million square feet to the medical center, which will be followed by growth of Stanford Shopping Center.

Though Stanford School of Medicine Dean Philip Pizzo touted the project's potential to "benefit this community for many decades to come," and Mayor Judy Kleinberg said it was "extraordinarily exciting," Vice Mayor Yoriko Kishimoto pulled back on the reins.

She cautioned her colleagues against rushing to approve any plans. On Dec. 18, the council is expected to give city staff the go-ahead to negotiate a development agreement with the university and a year-long environmental impact report (EIR) that would commence in January.

"To me, it's completely the wrong process," she said.

Kishimoto said that, for a city that debates 10,000-square-foot buildings, the 1.3 million-square-foot hospital expansion "is like asking us to swallow a bowling ball."

Councilman John Barton disagreed, saying Stanford's deadlines and the city's desire for a larger shopping center merited moving ahead.

"I'm comfortable with this approach. I think it is an extremely complex process," Barton said.

To bring the 1959 Stanford Hospital up to modern earthquake standards, new buildings will be constructed at 1101 Welch Road, followed by the current hospital facility's demolition on Pasteur Drive. The new main hospital will have private patient rooms for all 600 beds while Packard Children's Hospital, a much newer structure than Stanford Hospital, will add 104 beds to its 257.

Stanford also wants the city to grant special zoning allowances so that both hospitals can exceed Palo Alto's 50-foot height limit. The new, seven-story Stanford Hospital would be 115 feet tall -- still less than half as tall as Hoover Tower -- while Packard would grow to 85 feet.

Stanford hopes to break ground in 2009, with expected completion of Packard Hospital in 2013 and Stanford Hospital in 2015, according to Mark Tortorich, vice president of facilities for Stanford Medical Center.

Finishing the entire project will require construction through 2025.

Citing the new Stanford stadium as proof that the university manages difficult construction projects well, Councilman Jack Morton was more eager to move forward with the medical center. "I want to begin as soon as possible," he said.

However, members of the council expressed concern over potential impacts on traffic, housing and city resources from the major expansion.

Kishimoto warned about increased traffic, saying Stanford was not exempt from its responsibility to the environment.

"We committed to no net increase to greenhouse-gas emissions. It's a new world that we live in," she said.

Councilman Peter Drekmeier suggested ideas for how Stanford could mitigate the expansion's negative effects, such as adding housing on Welch Road for hospital employees, waiving rent Palo Alto pays for use of the downtown Caltrain station and contributing funds for below-market-rate apartments.

"This is a big project, almost the equivalent of adding a new shopping center," Drekmeier said. "I would like to work closely with Stanford to make sure this works," he said.

He also hoped that in exchange for the development, Stanford would agree to permanently protect its land in the foothills.

Though he recognized the enormous project would affect Palo Alto, Councilman Bern Beecham said it would ultimately garner community support.

"It's a resource that does impact us, but by God, how could we turn our backs on it?" he said.

Before discussing development agreements for both Stanford Medical Center and the shopping center on Dec. 18, the council will hold a study session on the mall expansion on Dec. 11.