If you hike the Hallmark Drive trailhead or let your dog off leash near the fishing lake below Ralston Avenue, you have probably heard at least three different versions of what is happening to the old college campus up the hill. Stanford was moving in. Stanford pulled out. The university is closing for good. Some version of the trail is getting fenced off. Most of that is either outdated or wrong, and the version that is actually true is more interesting than any of the rumors.
Here is the short version: Notre Dame de Namur University's 96.5-acre Belmont property changed hands in 2025, but not to Stanford, and not in the way most people assume. What changed and what didn't change split cleanly down a line most residents haven't drawn yet. The park is the sure thing. The mansion is the open question. That is almost the opposite of what the neighborhood grapevine has been saying.
Two Deals in One Year, and Only the Second One Closed
For nearly four years, the working assumption in Belmont was that Stanford would eventually take over the NDNU campus. Stanford entered into an option-to-purchase agreement with the university back in 2021, and the two institutions spent years developing a Conceptual Development Plan and an Environmental Impact Report with the city, exploring a project that could have brought 50 to 200 housing units to the Ralston Avenue property.
Then, in February 2025, Stanford walked away. The university cited factors that had shifted considerably since the original 2021 agreement, and Belmont City Council Member Gina Latimerlo pointed to a changed funding environment for research universities as part of the backdrop. The academic uses Stanford had envisioned would simply take longer to pencil out than the timeline allowed.
What happened next moved fast by university real estate standards. NDNU president Beth Martin has said she got a call from UC Investments, the University of California's investment arm, only a couple of days after the Stanford news broke. By May 27, 2025, the two sides had a signed agreement: UC Investments would acquire the entire 96.5-acre property, including the 46-acre academic campus and the 50.5-acre portion of Water Dog Lake that NDNU had owned since the Sisters purchased the land decades ago.
The Part That's Locked In
For residents, the single most consequential detail in the whole deal is the one that got the least attention when the sale was announced: Water Dog Lake stays a public park.
The preserve, which includes the stocked fishing lake and the trail network most people know through the John S. Brooks Memorial Open Space and Hidden Canyon Park, has been leased to the City of Belmont since 1965. That lease had roughly 40 years remaining at the time of the UC sale, and both UC Investments and the city have confirmed the arrangement continues unchanged. Trailheads at Hallmark and Lake Road, at 2400 Lyall Way, and at 2642 Carlmont Drive keep operating exactly as they have.
This matters because the property was genuinely at risk of a different outcome not long ago. The Stanford proposal excluded Water Dog Lake from its plans entirely, which means the current arrangement, where the lake is folded into the same sale but explicitly carved out of any redevelopment, is actually a better outcome for hikers than the deal residents spent years assuming would happen.
The Part That Isn't
Ralston Hall Mansion is a different story. The Italianate villa William Ralston built in 1868, later home to a girls' finishing school and then a private sanitarium before the Sisters of Notre Dame de Namur bought it in 1922, has been closed to the public since 2012 after an engineering assessment found the building couldn't be guaranteed safe in an earthquake on the San Andreas Fault. The docent-led tours, the weddings, the events in a ballroom modeled after the Hall of Mirrors at Versailles, all of that stopped over a decade ago, and estimates for the seismic and foundation work needed to reopen the building have run into eight figures.
The UC Investments deal includes a commitment to fund renovation of both Ralston Hall and its Carriage House. That is a real, meaningful change from the status quo, where the building had simply been sitting unoccupied while NDNU tried to raise money on its own. But a commitment to fund renovation is not the same as a construction schedule, and nobody involved in the deal has published one.
UC's own investment adviser, Dianne Klein, was candid about how open-ended the long-term picture still is. Asked about plans for the property beyond the initial lease period, she told the San Francisco Chronicle that the university envisions the site might eventually house "an institute or other such research center," language that describes a category of possible use, not a project.
So the honest answer to "when does Ralston Hall reopen" is that nobody has said, including the people who now own it.
What Five Years Actually Buys
The deal structure gives NDNU a leaseback of the existing campus facilities for up to five years, which is why nothing visible changed for students arriving for fall semester in 2025 and why nothing visible has changed for the neighborhood in the year since. The university's last remaining student housing closed in August 2025, a detail that matters more to campus operations than to anyone walking past the gates, since NDNU's enrollment has been almost entirely graduate and largely online since it ended undergraduate admissions in 2021.
The institution itself is not disappearing quietly. NDNU welcomed a new president, Dr. Leamor Kahanov, this year, and the Sisters of Notre Dame de Namur are marking their 175th anniversary in California, a milestone significant enough that Speaker Emerita Nancy Pelosi addressed the graduating class during the celebration. The university describes its own transition less as a closure and more as a long institution figuring out what a smaller footprint looks like after decades of shrinking on-campus enrollment, a trajectory that started well before the property changed owners.
What that means in practice: for the next several years, the campus looks the same from Ralston Avenue, classes continue in the same buildings, and the chapel and library stay in NDNU's hands as part of the sale terms. The bigger question, what a research institute or any other long-term use eventually looks like on 46 acres in the middle of a residential neighborhood, is a conversation that hasn't started in public yet.
The Quick Version, If You're Explaining This to a Neighbor
- Stanford is out. The option-to-purchase agreement from 2021 ended in February 2025 and was never exercised.
- UC Investments is in. The University of California's investment arm signed a deal in May 2025 for the full 96.5-acre property.
- Water Dog Lake's public lease continues unchanged, with roughly 40 years remaining as of the 2025 sale and the same trailheads in operation.
- Ralston Hall's renovation is funded but has no announced timeline or reopening date.
- NDNU keeps operating on campus for up to five years while it plans a smaller, likely San Mateo County location.
- No long-term redevelopment plan for the campus has been made public.
None of this is a reason to expect sudden change on Ralston Avenue. It is also not a reason to assume the story is finished. The most accurate way to describe where things stand today is that the part of the property everyone worried about is the part that's safe, and the part everyone assumed was settled is the one still being written.
If you've got questions about how developments like this touch specific streets or parcels near Water Dog Lake, or you're weighing a move in or around Belmont and want someone who tracks this kind of local detail closely, Debbie Livingston is happy to talk through what it means for your part of the neighborhood. Let's Connect — Start Your Home Search or Get a Free Home Valuation.
