As Stanford University prepares for its next phase of campus expansion, officials are confronting a daunting question: How do you add more than 2 million square feet of development without also adding traffic?

For the university, the question isn't purely academic. A key condition in its 2000 General Use Permit calls for Stanford to maintain a "no net new commute trips" policy at its campus. Thus, as Stanford's campus has expanded, the university has been forced to similarly expand its toolkit for dealing with traffic. Since 2001, Stanford met this challenge by introducing a vanpool program, launching East Bay shuttles, giving away free transit passes and adding more Marguerite buses. Its drive-alone rate plummeted from 72 to 50 percent.

"Despite adding more than 1 million square feet, Stanford has met this 'no net new trips' goal every year since 2001," Catherine Palter, Stanford's associate vice president for land use and environmental planning, said Monday night, during the university's presentation to the Palo Alto City Council.

Now, as the university is applying for a permit to add 2.275 million square feet of academic space and 3,150 housing units by 2035, city officials are wondering whether it can continue to gradually innovate its way out of traffic snarls. Its application, which is now being reviewed by Santa Clara County, identifies several new strategies it plans to pursue, including commuter buses, expanded local bus service and new bike improvements and parking policies.

Stanford is confident that it can find new and creative ways to get people out of cars. But some Palo Alto residents and city officials have serious doubts.

Last week, a group of Southgate residents poured their anxieties about Stanford's proposed expansion into a letter that challenged the university to do more to address the high number of non-residents who drive through and park on their streets. With traffic on Churchill Street getting worse each year, the neighbors wrote, Stanford's anticipated growth causes "additional alarm within our neighborhood."

In the letter, the Southgate residents urge Stanford to adopt technology that verifies that commuters are actually getting to campus by public transit, not "driving and parking adjacent to a Marguerite shuttle route in a local neighborhood."

"We are particularly concerned with the lack of a truly verifiable plan for monitoring and dealing with off campus traffic and parking impacts, particularly when we consider the manner in which the Transportation Demand Management (TDM) plan proposals are set forth in the Stanford application," the letter from Nancy Shepherd, Jim McFall, Christine Shambora, Keith Ferrell and Tom Vlasic states. "We find them inadequate and to rely on only committing to partially solving problems well after the impacts are felt by the adjacent neighborhoods."

The neighbors also assert that the Southgate resident believe Stanford "does and will contribute to increased traffic congestion in and around our neighborhood, the city and other communities and therefore should be responsible for this impact with mitigations that include clear and specific verification methods that ensure workers offered TDM programs are using public transit for the entire commute."

The council had its own questions and misgivings. Councilwoman Lydia Kou told Stanford officials that even if Stanford meets its campuswide goal, its growth brings unwanted impacts to particular sections of the city.

"While you're saying 'no net new commute trips,' for us who live here -- we don't feel that," Kou said. "We feel there is impact here."

She was also one of several council members who encouraged Stanford to get more involved in supporting regional transportation projects such as the electrification of Caltrain.

"If we're going to continue to grow the way we are ... to be successful in the 'no net new commute trips' goal, it has to be viewed at a bigger level, higher level," Kou said. "I hope you can commit to lobbying the state and federal (government) for a more strategic outlook on transportation."

While Stanford believes it can keep traffic from getting worse, the application proposes a hedge: a provision that would allow the university to pay a fee to Santa Clara County for traffic improvements if it fails to meet the "no net new trips" goal.

Mayor Greg Scharff suggested Monday night that one way Stanford can address traffic issues is by supporting the the Palo Alto Transportation Management Association (the city's new nonprofit) and Stanford Research Park's growing transportation-demand-management program. He also noted that California Avenue will soon need to have its own Transportation Management Association. He encouraged Stanford to help get that organization off that ground.

"I think we can create linkages between California Avenue and Stanford Research Park and solve trips in both of those," Scharff said. "Everyone benefits."

Scharff also suggested that at least some of the fees for mitigating traffic should be provided to the city rather than going entirely to the county.

"I think it's helpful for us to have it or at least share it in some way," Scharff said. "I think there will be impacts to Palo Alto from all of this."

Others were more optimistic. Councilman Adrian Fine lauded Stanford for its efforts and said the university should be "celebrated" for serving as a great example of low-impact growth. To assuage anxieties, he urged Stanford officials to explicitly share their traffic-related metrics and methodologies with neighbors.

Stanford officials acknowledged that it's not clear yet exactly what the university will do to meet its goals for the coming General Use Permit. That, however, was also the case in 2000. Jean McCown, Stanford's assistant vice president and director of community relations, said one of the strengths of the last permit was the fact that it created a clear goal while giving the university the flexibility to do whatever it takes to meet the goal.

"The exact technologies we use and the tools we use are left to us," McCown said. "I think that's one of the hallmarks for why this has been so successful."