A proposal to transform the Palo Alto Junior Museum and Zoo into a larger, safer and more whimsical habitat for humans and animals alike cleared a critical hurdle last week, when the nonprofit group spearheading the project completed its $25-million fundraising campaign.

Once completed, the popular Rinconada Park destination will be equipped with new classrooms, better storage areas, improved vehicle access and a "loose in the zoo" area -- a netted enclosure that will allow children to discover birds, insects and other zoo residents on their own turf. Within the space, there will be enclosed exhibits for some of the zoo's larger and more famous denizens, including bobcats, raccoons and meerkats.

According to city staff, the new museum would be better equipped the serve the roughly 150,000 visitors who come in every year and the roughly 19,000 children from Palo Alto, East Palo Alto and Mountain View who come in annually to learn about nature. A recent report from the Community Services Department notes that while museum staff continues to offer "outstanding educational programs, quality experiences for the drop-in visitor, and reliable animal care, they are severely limited by lack of office, preparation and storage spaces." Furthermore, the inadequate storage spaces in the 1941 building make it impossible for the zoo to obtain accreditation from the Association of Zoos and Aquariums. The retrofit will change that.

John Aiken, the museum's executive director, said in a statement that it's important for the zoo to "retain the intimate and child-like qualities of the current facility."

"We will add more interactive exhibits and habitats that promote questions in young children without removing the safe environment in which they can explore," Aiken said.

The expansion project is being spearheaded by the Friends of the Palo Alto Junior Museum and Zoo, a nonprofit that has raised $10 million in private donations from more than 165 contributors in the community. This made the group eligible for a $15-million matching grant from the Peery Foundation. Aletha Coleman, president of the Friends group, said in the announcement that community treasures like the Junior Museum and Zoo "would not be possible without the generosity of our private donors.

"We want to take a moment to celebrate and thank our donors for making the new JMZ a reality," Coleman said.

David Peery, managing director of the Peery Foundation, said in announcement that he believes the zoo "has the ability to transform the lives of young children through high-quality and hands-on science instruction."

"The JMZ has a demonstrated history of teaching vital science education to generations of children, regardless of their economic background," Peery said. "Our family is excited to help make the new Palo Alto Junior Museum and Zoo a reality, and ensure it will continue to bring science alive for future generations in this community."

While final design for the new museum is still undergoing revisions and has not yet been approved, the success of the fundraising effort is a huge step forward for a project that has received overwhelming support from the City Council. Unlike other major infrastructure projects in the city's pipeline -- a list that includes a new police headquarters, two fire stations, two parking structures and a bike bridge -- this one is funded by private money and offered to the city as a gift.

During a November discussion of the project, council members enthusiastically endorsed the expansion, which Tom DuBois called a "fantastic project." Then-Mayor Pat Burt noted that the funding is coming entirely from private sources and said he favors having the city "bend over backwards to try to help in any way we can."

Current Mayor Greg Scharff also highlighted the project last week in his "State of the City" speech and called the effort to expand the museum "an extraordinary partnership between our citizens and the city of which we can be very proud."

Even with the money in hand, the project still has a few hurdles to clear. The biggest of these is approval the Architectural Review Board, which last month reviewed the latest designs and found them lacking. Board member Peter Baltay said that he is "excited about the project," but argued that the character of the proposed museum is not "whimsical" and "not appropriate" for its function.

Board Chair Robert Gooyer agreed and noted that "the most child-friendly and imaginative thing is the sign outside."

"Once you get past the sign, it's a bland box," Gooyer said.

Museum officials hope they can make the needed adjustments and win the board's approval in the next few months. According to the recent announcement from the Friends group, the group expects the council to sign off on the project this summer and for groundbreaking to take place in spring 2018. If things go according to plan, the new museum would reopen its doors in 2020.