When the Palo Alto City Council launches its review Monday of Castilleja School's contentious plan to reconstruct its campus, it will kick off a process that will influence not just the Bryant Street institution but also the city's process for evaluating future major developments.

The school, which was founded in 1907, has been in the spotlight since 2016, when it submitted plans to modernize the campus. While the plans have gone through numerous revisions since then, the passionate feelings on both sides of the debate remain the same. The school's supporters say that Castilleja's proposal will enhance the institution and the broader community. Opponents say the plans would burden the single-family neighborhood with cars and noise.

In the months leading to the council's March 8 hearing on Castilleja, hundreds have submitted letters urging the city to support the school and advance the project.

"We must do all we can to protect, preserve and further the mission of this valuable community resource for our next generation of female leaders," High Street residents Dick and Anne Gould wrote in one such letter last week. "Castilleja has shown how this can be done, while protecting our neighborhood and environment — the school's leadership is to be commended for their 'listening' and for their efforts."

The project's many opponents counter that the plan is both illegal and insensitive to neighborhood concerns. They point to the school's history of exceeding its enrollment cap — a transgression that prompted the city to issue a $265,000 fine in 2013 — and argue that its plan to bump up the number of students from 426 to 540 and to build a garage is incompatible with the character of their neighborhood. The plans, they contend, should be significantly scaled down and the new garage eliminated altogether.

"To allow this increase right now makes a mockery of city laws and regulations," Mary Sylvester, who lives near Castilleja and who is a member of the group Preserve Neighborhood Quality of Life Now, told the council this week.

Both views will get plenty of airing in the next two weeks when the City Council is scheduled to hold hearings on what is easily this year's most complex and divisive development project. But even as Castilleja continues to be lionized and demonized by its supporters and opponents, the council's verdict may come down less to the passionate feelings on both sides and more to technical interpretations of ambiguous zoning laws.

Is the garage a garage?

Among the most critical questions that the council will weigh is: Should the new underground structure be considered a garage? To a layman, the answer is clearly yes. Castilleja has referred to the subterranean facility as a garage in its plans and the city's documents, including the environmental analyses and the statement of findings, similarly use the term routinely in describing the project.

Yet when it comes to code, staff had determined that the subterranean facility with 78 parking spaces is in fact not a garage but rather a "basement." That's because the city's zoning code defines a "garage" as a "portion of a principal residential building or an accessory building to a residential use designed to be utilized for the parking or storage of one or more motor vehicles, which is enclosed on three or more sides and covered with a solid roof." Because the Castilleja is not a residential use, the city's planning and legal staff had concluded that its garage is not, technically, a garage.

"Since these definitions relate to residential buildings and uses — they do not apply to the proposed parking facility for a non-residential use," a new report from the Department of Planning and Environment states.

In explaining staff's conclusion that the facility is a basement, Deputy City Attorney Albert Yang told the Planning and Transportation Commission in September that basements are defined by code as structures that are at least 50% below ground. Thus, "this underground parking facility could qualify with that definition."

"We believe it's a reasonable interpretation of our code," Yang said at the Sept. 9 meeting. "These are areas where there is some gray area."

The distinction between a "garage" and a "basement" is a critical one for Castilleja. Under the city's zoning code, underground garages are illegal in R-1 neighborhoods; basements are not. Garages also count in tallying up a project's gross square footage; basements do not.

Thus, if the council rejects staff's logic and concludes that Castilleja's underground parking facility is in fact a garage, the school may be forced to either remove the structure from its plans or scale down its expansion plan.

Not everyone agrees with this interpretation. Critics of the Castilleja proposal and even some planning commissioners have characterized the staff interpretation as a major giveaway by the city to the school.

"How can a parking garage not be a parking garage?" Becky Sanders, co-chair of the umbrella group Palo Alto Neighborhoods, asked at a Nov. 4 hearing of the planning commission. "How can it not be included in the floor area when the zoning code clearly states that it's included?"

The thorny question has already stymied the commission, which split 3-3 over the issue when it was reviewing the project in October and November. While three commissioners — Bart Hechtman, Michael Alcheck and Giselle Roohparvar — deferred to the city's planning and legal staff, three of their colleagues — Ed Lauing, Doria Summa and Cari Templeton — couldn't make the finding that supported staff's interpretation.

Templeton, who otherwise supported the Castilleja project, observed during the commission's Nov. 18 discussion that the underground garage is "a big departure from what other properties in the area are allowed to do." She also suggested that if the project goes through, the city will see more requests for underground facilities.

"We don't want to see an inadvertent side effect of abuse of this particular kind of structure," Templeton said.

Summa agreed.

"I just can't find anything in the code that allows for the floor area of the parking garage not to be counted," Summa said.

How many car trips?

For critics of Castilleja's expansion, it's not just the new garage that's the problem. It's also the cars. Over the course of the long planning period, neighbors have complained that allowing the expansion would endanger bicyclists on Bryant Street and create parking problems for neighbors whenever the school hosts major events.

Castilleja has maintained in its plans and its comment letters that it would adopt a more robust "transportation demand management" plan that would minimize the number of vehicle trips to campus. Its proposed program includes measures such as shuttles, carpool programs and mandates limiting single-occupancy driving by school staff. As a further assurance to neighbors, the city and the school had agreed to stringent traffic-monitoring requirements. Under the proposed system, if the school were to exceed allowed traffic limits, it would have to freeze enrollment increases.

To Castilleja's chagrin, the planning commission decided on Nov. 18 that this is not enough. Rather than adopt the school's proposed measures, which the environmental analysis showed would result in "less than significant" traffic impacts, the commission voted to institute a more stringent standard of "no net new trips." While two commissioners, Alcheck and Hechtman, argued that this standard is too rigid, five others supported the proposal from Commissioner William Riggs, who proposed the "no net new trips" policy, which is currently in effect at Stanford University.

"We should hold them to the same standard that we hold Stanford to," Riggs said at the Nov. 4 meeting.

The new standard would limit the school to no more than 1,198 average daily vehicle trips to and from Castilleja, the number of trips that the environmental impact report estimated for the school's current population of 426 students. Castilleja would need to adopt more aggressive transportation measures if it wants to enroll 540 students.

Castilleja has argued that the commission's recommendation — which would also commit the school to not exceeding 383 trips during the morning peak commute time — goes too far. School officials have pointed to its history of reducing traffic and recent analysis showing that the traffic impacts of the school's expansion will have a "less than significant" impact on the neighborhood. Its proposed transportation measures include providing transit passes, creating a "guaranteed ride home" program for those who don't drive to school, off-site pick-up areas and a bike-share program on campus.

During recent hearings, Castilleja officials have also pointed to the large number of traffic programs that the school already has in place, including vans that shuttle to Caltrain stations and a policy that prohibits employees to come to work in a single-occupancy vehicle more than twice a week. Nanci Kauffman, head of Castilleja, told the planning commission during an Oct. 28 review that the policies have helped the school reduce its vehicle trips by 31%.

"I don't know another employer in Palo Alto who has the same stringent requirement for employees," Kauffman said.

Mindie Romanowsky, an attorney representing Castilleja, urged the commission in a Nov. 17 letter to reconsider and reject the "no net new trips" standard. Upholding it, she argued, "will equate to the City holding the School to an unreasonable and higher standard than the City would require of any other project and could serve to paralyze the school's ability to use their property and to grow in a meaningful way."

Two planning commissioners shared this view. Hechtman and Alcheck both suggested that the city's initial proposal — tying traffic impacts to allowed enrollment expansion — provides a sufficient "safety net" to ensure that traffic conditions will not deteriorate. The conditions thus ensure that the city will not be "stuck in traffic without recourse."

"The conditions create a framework with which the school would have to meet certain hurdles before they could continue to grow," Alcheck said.

The student dilemma

While most development decisions are binary in nature, subject to either approval or denial, the Castilleja expansion presents the council with an unusually broad discretion with which to tinker. In considering a new conditional use permit for the school, for example, the council will have to weigh a number of questions that have already generated significant debate: How many special events should the school be allowed to host? (The planning commission settled on 74 per year.) When should these events be allowed to take place? (No more than five on Saturday evening and none on Sunday, according to the proposal.) Should Castilleja be forced to modify its tree plan, which calls for removing 18 trees and planting 99 trees? (City staff had concluded that the school's tree-removal plan is legal, a finding that PNQLNow members dispute.)

On Thursday, planning staff had identified another complication in the approval process: a Castilleja neighbor discovered that the floor area of an existing classroom building is not 42,000 square feet, as staff had initially thought, but 35,000 square feet with a 7,000 square foot basement -- a basement that is exempt from calculation. Because Castilleja has expressed its commitment not to add above ground square footage as part of the reconstruction, the finding means that the school now has to trim 4,370 square feet from its proposed project to meet this goal. It also means that the project will have to undergo another review by the Architectural Review Board for the revised design and that whatever action the council takes on March 15 will not be the final approval.

The council will, however, confront in the next two weeks another key question that is at the heart of the Castilleja debate: How many students should the school be allowed to have?

The school has been gradually decreasing its annual enrollment since 2013, when it was found to have exceeded the cap of 415 students by 8%, or 33 students. In 2020, the school was still overenrolled, with 426 students. If its project is approved as proposed and the traffic conditions are met, it would be able to gradually ramp up enrollment to 540 students.

In explaining its decision to seek an increase to 540 students, Castilleja officials have pointed to both their desire to further the school's mission to educate more young women and to their recent traffic studies, which indicate that going to that level would not worsen traffic around the school.

"That was a number that we derived primarily on the basis of both what serves the school program but also to be sure that we could maintain the promise of not having a traffic impact," Kauffman said on Oct. 28.

But many neighbors, and some planning commissioners, believe 540 is too many. Lauing and Summa both suggested that 450 may be a more reasonable number. Once Castilleja proves that it can manage that many students with no neighborhood disruptions, they argued, it can seek further increases.

Lauing suggested that limiting the enrollment number to 450 would minimize the risk that the project would worsen area traffic. If Castilleja's traffic-mitigation strategies succeed, Castilleja should have no problem getting the city's permission for additional increases, he said.

"I think given the risks now, the city needs a safety net," Lauing said. "We know it's easier to manage TDM with a lower number of students because Castilleja is successfully doing that right now and I salute them for that. But it gets harder as enrollment increases."

Some of the project's critics support this plan. Hank Sousa, a Castilleja neighbor and member of PNQLNow, said he and others in his group would be comfortable with an 8% enrollment increase, bringing the number to 448. Such an increase, he wrote in a Feb. 18 letter to the council, would limit the number of cars in the neighborhoods and obviate the need for a new garage while still allowing Castilleja to grow.

"We feel a modest enrollment increase and some revisions to the proposed plans can work for the neighbors," Sousa wrote in a Feb. 21 letter to the council.

That view, however, has been rejected by both the city's planning staff and the majority of the planning commission, which supported allowing Castilleja to move to 540 students. Planning commission Vice Chair Giselle Roohparvar spoke for the majority when she argued that the school should be allowed to go as high as it wants to on enrollment, provided it can contain the impacts of its growth.

"I don't think there is a problem with having 540 — or however many — students, as long as there's no impact on traffic," Roohparvar said at the Nov. 18 meeting. "And that can be managed."

City staff is also supporting Castilleja's proposal for increasing the student population to 540, provided that its traffic impacts remain low and that the increases are limited to no more than 25 students per academic year. A report from planning staff notes the prevailing perspective over the course of the recent hearings: "The number of students enrolled at the school was less important than Castilleja's ability to meet its trip reduction targets."

The council is expected to tackle the question of whether or not to approve an expansion to 540 students or to mandate a more gradual growth plan on March 15, its second scheduled hearing on the Castilleja project. The first meeting, on March 8, is reserved largely for public comments.

Editor's Note: This story was updated to reflect the memo staff had sent out on Thursday night, indicating that Castilleja will need to revise its plans to reduce gross floor area by 4,370 square feet.