The Other Side of the Creek: The Atomic Age at Stanford

Editor’s note: “The Other Side of the Creek” is a series designed to capture the life and spirit just beyond San Francisquito Creek — the shared landmark separating Menlo Park from more southern communities.

Introduction

There are corners of Stanford where the ground has held more than one kind of future. The Ryan Lab is a prime example. Originally established in 1926 for spectacular high-voltage electrical testing, it was later retrofitted in the 1950s to house a small pool-type nuclear training reactor. Today, the site serves a much quieter purpose as the Ryan Court residential community.

Stanford had broader atomic-age interests during the mid-twentieth century, but this article is narrower. It follows the physical site and documented history of the Harris J. Ryan High Voltage Laboratory: its first life as an electrical-testing landmark, its later use as a nuclear teaching-and-research facility, and its eventual removal from the campus landscape.

First Life



The site’s first future began in fire-white voltage and later — briefly, quietly — shifted into the blue-glow vocabulary of the Atomic Age.

In its first life, the Harris J. Ryan High Voltage Laboratory was built for spectacular electrical work. Named after a Stanford engineering pioneer who shared the Edison Medal ranks with Nikola Tesla and Alexander Graham Bell, it opened in 1926 as the world’s largest university electrical facility. Its primary mission was ambitious: to solve the massive engineering challenges of transmitting electricity over hundreds of miles to power the booming American West.

The sheer power of the facility demanded an industrial, cavernous, hangar-like structure, simply to give its giant transformers enough clearance to prevent millions of volts from accidentally arcing into the walls. At its dedication, Stanford proved the lab’s capabilities by staging a stunning public demonstration around its 2,100,000-volt test station, generating an artificial lightning bolt across a 20-foot gap — a world record for commercial-frequency voltage at the time.

Transformation To Atomic Campus

By the mid-1950s, Stanford’s Mechanical Engineering Department had begun building a nuclear program under Professor George Leppert. In 1958, the old high-voltage lab — a space originally scaled for artificial lightning — was remodeled to support nuclear teaching and research. The program started with a subcritical assembly, captured in a 1958 university centennial photo of Leppert and graduate student Gary Vliet, marking a profound period of transformation.

The detail that still surprises Peninsula readers is not the concept of a teaching reactor — it’s the location. This was not a distant, heavily guarded test site in the desert. It was right on Stanford’s campus near Palo Alto, housed in a building that already held decades of electrical history.

Tapping into the region’s emerging commercial atomic industry, the reactor was manufactured just down the road by General Electric’s Atomic Power Equipment Department in San Jose. The design also belonged to a familiar midcentury research-reactor category: a pool-type reactor built for training, experiments, and hands-on nuclear-engineering instruction rather than commercial power generation.

The licensing timeline matters. In November 1959, the Atomic Energy Commission issued Construction Permit No. CPRR-46, authorizing construction of a 10-kilowatt pool-type nuclear reactor facility on Stanford’s campus near Palo Alto. After the reactor was completed and inspected, the AEC issued Facility License No. R-60 on September 28, 1961, authorizing Stanford to possess and operate the 10-kilowatt reactor facility.

A pool reactor is exactly what it sounds like: the core is submerged in a deep tank of water. This specific design helps explain why the government allowed a nuclear core on a college campus. The Stanford Pool Type Reactor, or SPTR, was not a power-generation reactor. It was a small teaching-and-research reactor, operating at a maximum of 10 kilowatts thermal — roughly the thermal output of a few household electric ovens. It required no pressurized containment dome or massive cooling tower. The pool provided cooling through natural convection and served as an effective radiation shield, creating a low-power environment designed for student training and research.

By the mid-1960s, this was not just a novelty bolted onto campus; it was part of Stanford’s evolving engineering footprint. The 1926 structure now held labs, classrooms, and offices for the Nuclear Division. It also hosted a curriculum that is astonishing by modern standards. In 1965, Professor Paul Kruger launched Stanford’s first course in nuclear civil engineering, funded through a training grant from the Public Health Service and the AEC. He brought in scientific figures such as Edward Teller and Nobel laureate Willard Libby as guest lecturers. In the context of the federal Project Plowshare initiative, Kruger’s civil engineering students studied the feasibility of using peaceful nuclear explosions for large earth-moving projects, including artificial harbors and canals.

That point should be kept narrow. This article documents the Ryan Lab reactor site, not every atomic-related activity or theoretical nuclear-engineering discussion connected with Stanford. Some oral histories have associated Kruger’s Plowshare teaching with high-explosive row-cratering demonstrations in the nearby foothills. I have not independently verified those reports in official university records, and they should not be treated as evidence of additional reactor activity on campus.

Stanford’s facility fit a wider national pattern that reads as almost unbelievable today: midcentury America placed training and research reactors on college campuses to build a nuclear workforce. The Stanford Pool Type Reactor operated for a relatively brief period before Stanford sought authority to dismantle the facility in the 1970s.

The Quietest Ending

During the atomic optimism of the 1950s and 1960s, it was common for major research universities to house small-scale nuclear reactors for training students and running experiments. Over the following decades, many of those campus reactors were shut down and dismantled.

Maintaining aging nuclear infrastructure became expensive. As the federal government pushed to remove highly enriched uranium from civilian sites, the costs of converting fuel, managing security, and meeting regulatory obligations made many campus reactors harder to justify. While a few institutions, such as MIT, adapted and kept their reactors running, Stanford’s facility joined the broader wave of closures.

The end of the Ryan Lab was not simply a matter of tearing down an old building. Stanford applied in September 1973 for authorization to dismantle the Stanford Pool Reactor and terminate Facility License No. R-60. The Atomic Energy Commission authorized dismantling in 1974, subject to decontamination, radiation-survey reporting, and inspection. The later NRC license-termination notice stated that the facility had been dismantled and decontaminated, that the component parts and fuel had been satisfactorily disposed of, and that NRC inspection and radiation surveys confirmed the area was available for unrestricted access.

Publicly discussed records also indicate that residual radioactivity was not spread broadly across the property but was limited to a small area beneath the old reactor tank. In 1988, Stanford reported a low-level radioactive patch of concrete, about three by three feet, beneath the tank floor. Before demolition proceeded, crews removed the top two inches of concrete from that specific area and disposed of the material as radioactive waste.

That detail matters because it closes the logical gap between reactor and residence. The former reactor site was not simply converted into housing without a cleanup step. The building and site went through regulated decommissioning, testing, and license-termination review before the land passed out of nuclear-facility use.

And what is there today? Housing — specifically, Stanford’s on-campus residential fabric in the Ryan Court area. Stanford’s own housing listings show the quiet community here: “Ryan Court (Stanford Rental Homes).” The creek corridor is still the geographic tell, but the lab structure is gone; the facility was demolished in the late 1980s. There is no monument, no dramatic marker, and no historic plaque — just daily domestic life where high voltage once arced and, later, a small licensed reactor once operated.

That is the quietest ending: a hangar-like building that held 2.1 million volts, then a 10-kilowatt pool-type teaching-and-research reactor, entirely replaced by a campus neighborhood most people pass without a second thought. If you have memories — an open house, an old professor’s aside, a parent who worked nearby, or a half-remembered line about “the reactor pool” — that is the material local history depends on. The Peninsula’s past often is not loud. It is found in the things that hummed quietly, hidden inside buildings whose functions everyone assumed they understood.

Photo notes

Top photo: “Stanford University, 9-18-26, Dr. H. Ryan’s Electrical Laboratory” typed on the back.

Second photo: “E 178 Condenser connections at the laboratory looking directly at the building” typed on the back. The hangar-like electrical engineering facility was built for very large high-voltage experiments. Contemporary Stanford descriptions note that it was located near “Frenchman’s Dam” on or along Stanford Avenue, on the campus edge toward the foothills.

Third photo: A rare view of Stanford’s Nuclear Technology Laboratory, in the former Harris J. Ryan High Voltage Laboratory in 1961.

Fourth photo: Engineering professor George Leppert, right, and graduate student Gary Vliet take measurements in Stanford’s subcritical nuclear assembly, 1958. The apparatus operated like a reactor but could not sustain a chain reaction. It was located in Stanford’s Nuclear Technology Laboratory.

All photos courtesy Stanford University Libraries, Department of Special Collections and University Archives.

Sources and related records:

Disclaimer and Legal Notice: This piece reflects independent research and historical commentary. The content was researched and revised with the assistance of artificial intelligence tools, including support for fact-checking. AI assistance serves as an editorial aid and does not replace human authorship or independent judgment. No guarantee is made regarding the accuracy or completeness of the data, and content is subject to updates. This article does not constitute professional advice or an official institutional statement.

To request corrections or updates, please contact the author, Ardan Michael Blum, at https://links.ardanmichaelblum.com.