SANTA CRUZ — University of California regents approved a hotly contested plan to develop the UC Santa Cruz East Meadow as part of a larger housing project with one condition: Skeptical about claims made by the campus administration about the high cost of alternate sites, the approval is contingent on a more detailed financial review over the next month.

The decision on the project, called Student Housing West, came Wednesday after more than a year of debate between the UCSC administration and an unprecedented coalition of project opponents, including faculty, prominent alumni leaders, former regents and officials.

UCSC’s top administrators have said that the least expensive alternative to developing the East Meadow, seen by some as an iconic natural gateway to the sprawling campus, would cost an additional $90 million.

Some regents said those projections don’t seem plausible. Regent Hadi Makarechian, who chairs the regents Finance and Capital Strategies Committee where the project was considered, said he does “not buy” that moving the project to another site would drive up costs so much.

“Those are the numbers that, if they’re real, somebody show us,” said Makarechian.

Makarechian and fellow regents Lark Park and George Kieffer now have a month to review the university’s confidential financial projections and decide whether to revoke the committee’s approval.

Almost everyone involved agrees that the campus needs more housing, and the sooner the better. Student Housing West would add roughly 3,000 student beds to campus — just enough, according to campus officials, to meet the needs of current students who are crammed into converted dorm common rooms, or languishing on long wait lists and forced to fend for themselves in Santa Cruz’s costly and competitive rental market.

The vast majority of the student housing — more than 2,700 beds — is planned for a site on the western campus, and is widely supported.

But fierce debate has raged for more than a year about the decision to move part of the project to a second site to 17 acres of the undeveloped East Meadow near the campus entrance, where 140 units of student family housing would be built alongside an expanded child care center for children of students, faculty and staff.

The two project sites can’t easily be separated, according to UCSC officials, because the current child care center and student family housing must be demolished to build the 2,700-bed complex.

Project opponents, which include a prominent group of 44 alumni leaders, former regents and a former campus architect , say that developing the meadow would be a radical departure from the land-use philosophy that shaped UCSC’s campus and provides it with its unique natural appeal. They have accused the administration of failing to seriously consider alternative sites and playing coy with cost estimates and other project specifics.

Another faculty- and alumni-led group of opponents, the East Meadow Action Committee, have promised to pursue litigation if the project moves forward, and an online petition opposing the project has so far been supported by more than 80,000 people. Current students had remained largely quiet about the development until recently, when the Student Union Assembly passed a resolution calling on the regents to delay approval another two months to give the students more time to consider the project.

“I wish this project were not so controversial,” UCSC Chancellor George Blumenthal told the regents Wednesday. “It pains me to see esteemed and beloved friends of the campus opposed to this project.”

Pressed by the regents about how thoroughly alternate sites had been vetted, Blumenthal insisted his administration thoroughly considered all alternatives and found no feasible option that wouldn’t drastically drive up the cost of housing for students with families.

“If there were a simple solution to that question, we would have brought you that simple solution already,” Blumenthal told the regents.

The decision in front of the regents committee Wednesday involved approving the project’s final environmental impact report, approving project design, and approving an amendment to UCSC’s Long Range Development Plan — necessary because the meadow had been designated as campus resource land, protected from development.

The regents committee approved all three facets, contingent on the planned financial review. A decision on business terms with the project’s private developer, Capstone, was expected to be made later Wednesday in a closed session.

Ken Feingold, a former regent and former president of the UC Santa Cruz Alumni association who is among the project’s prominent critics, said he continues to believe it would be a mistake to develop such a large piece of the meadow to house so few students. But he lauded the regents for taking seriously the concerns raised by himself and others and said he’s optimistic about the financial review.

Feingold said he plans to push to make the detailed cost-projections for alternate sites public, which UCSC has repeatedly declined to do, citing impacts on its contract negotiations.

“I don’t agree 100 percent with the outcome, but I commend the regents for understanding the importance of this decision on the campus,” Feingold said.