[Under University of California, Berkeley]

April 29, 1999

A chronicle of our exploration of the Main Campus Steam Tunnel at the University of California, Berkeley

``Walking across campus at night, the air is quiet yet full of noises: the spray of sprinklers on the grass; the muffled roar of ventilation systems; the whine of electric motors in the night campus shuttle bus; the hiss of leaking steam. Steam. It was because of the steam that I was to meet a friend at one o'clock in the morning in west central campus. The Campanille's great clock above indicated the decided-upon time; I found my friend locking up his bike nearby and walked towards him. An owl flew overhead; raccoons scavenged in the grass: the campus slept...''

This web site is part of the Urban Explorers Network.


Dev Chatterji, a Daily Cal columnist this summer recently wrote a column (``Berkeley Underground'') describing a journey through the tunnels he undertook with friends as a relief from boredom. I think he's more interested in developing his own personal conspiracy theory than the actual facts of the steam tunnel. For instance, he asserts: ``They were initially created as a means of transportation between the original buildings'' and ``You can use the Tunnels to enter just about any building you want.'' To the best of my knowledge niether of these statements is true, but B and I are nonetheless interested in verifying/debunking them. Perhaps more interesting is the official response by a vice chancellor, ``Campus Steam Tunnels Are Not Toys'' asking the Berkeley public to please stay out of the dangerous tunnel environment. Links to both articles are available below. If you can provide any insight, feel free to email me.

More to the point, Agents of Splorg still in Berkeley report that casual (eg, unauthorized) tunnel access is now impossible, as all the known gratings have been secured. Moreover, the ``not toys'' statement provides an explanation: gratings were left unlocked in the past to provide escape routes for tunnel workers in the case of emergency, but now the gratings have allegedly been equipped with some kind of locking mechanism making them easily openable from inside but not outside.

Related: a look inside the cogeneration plant

Achtung! Warning!

One shouldn't go into the steam tunnels without a guide from physical plant services. Dangers lurk in the tunnels. The most pressing are hot steam and the probable presense of asbestos. Other possible dangers include but are not limited to heat exhaustion or physical injury, exposure to radon gas, caustic chemicals, and a multitude of other possibilities.

Campus documents indicate that ``Asbestos was formerly used extensively as a building material, and large quantities were incorporated into campus buildings and underground utilities.'' The EPA maintains that there is no safe level of exposure to asbestos.

UE Related articles from the Daily Cal

``Where is the entry point?'' I asked, after the usual greetings.

``See that grating sixty feet ahead?'' Brandon replied. I acknowledged, then Brandon continued: ``That's it. Our entry point.'' Soon we arrived. There was nothing particularly unique about this grating; it was identical in appearance to scores of other such gratings across campus, but with an important distinction: this one was not welded closed or locked. Like a scene from a Bond movie, we scoped out the surroundings. After waiting for some pedestrians to leave the field of view, Brandon quickly lifted the grate, and directed: ``Go in.''

I jumped into the dark abyss beyond the grating, stumbling down a ladder I couldn't see, into the thick Venusian atmosphere. My boots hit concrete, and I moved out of the way for Brandon to come down after me, swinging the grating closed. Now in the seclusion of the tunnel it was time to reconfigure. With some flashlight illumination, it was clear: we were now in the UC Berkeley Steam Tunnels. It was exciting.

Why are there tunnels, anyway?

Steam is generated at in the Heating Plant on Cross Campus Road, just northwest of Harmon Gym. The steam pressure is used to generate electricity, which supplies the energy needs of the UC Berkeley Campus, and then the steam is piped to buildings on campus, where it is used for heating and cooling. How is steam used to cool buildings? We speculate that the steam pressure is used to drive the air conditioning compressors. In order to get to each building in campus, the steam is directed under pressure through a network of pipes in a corresponding network of tunnels under the campus. After the steam fulfills its function in a particular building, it is returned through another pipe through the same tunnels to the Heating Plant, where it is recycled. This is why there are steam tunnels on campus. The steam tunnels are also used to route network and phone cable, and electrical conduits. However, the hostile environment (high temperature and ambient moisture) makes the steam tunnels an undesirable location for such services, and so when possible they are routed via other means. The steam system is very old, and there are many leaks. This leaking steam can be seen in many places on campus where it visibly vents from gratings and man-holes in the ground. (No, contrary to popular misconception, the steam does not vent from the sewer.) Currently the steam tunnels are undergoing renovation; when the project is complete, in approximately a year, there supposedly will be no leaks, a boon to the steam-tunnel traveler.

The Physical Plant, the network of infrastructure that makes a campus or a city work, providing electricity, heat, water, transportation, and so forth, has always fascinated me. When considering attending Cal Berkeley for undergraduate studies, I checked into the steam tunnel culture at Cal, already aware of the almost canonical culture of legend at MIT and at Caltech, the origin of the word ``hack.'' Even UCLA has the famous underground bridge, and maps of tunnels at many institutions are widely available, published by enthusiasts on the Internet.

I was dismayed to find almost no reference to the steam tunnels at Berkeley, save for an article in the Daily Californian some years ago, and the web pages of campus information services, describing how and where ethernet is routed between buildings, and how the ethernet is to be upgraded in the future, taken out of the hostile steam tunnels. This, I was to find out, is only one incongruity in the ethos of the Cal student body -- on the one hand, historically rebellious, progressive, inventive, home of an ideology that crowned a decade, and the technology that crowned an age, and on the other hand, the sons and daughters of middle class California, conformant in their own way to an unacknowledged culture-less homogeneity. But that's another story.

``The steam as it leaves the gas turbines is high-temperature, but low-enthalpy,'' Brandon explained, citing his knowledge of Thermodynamics. ``Circulating it through campus cools it, which is necessary before it is recycled.'' Or something to that effect; I don't remember his exact words, but they made me want to take a class in thermodynamics.

The first thing we did, after looking around with flashlights, was to take off our jackets. The campus above is usually fairly chilly (by our Southern California standards, at least) at night, especially during the winter, but the steam tunnels are always a toasty 100-degree-Farenheit or more in particular sections, with close to 100% humidity to boot.

It was time to explore. We began heading East, up campus, away from the power plant. To our left ran three large insulated steam pipes. To our right, a periodic line of industrial-looking fluorescent lamps created an X-files-esque landscape, leading one to almost expect to see the dull green fluorescent lamps come on all at once, illuminating the way for a stream of big-eyed grey aliens to run past, through the 8'x4' tunnel to a clandestine facility deep in the salt mines. We walked along. The tunnel was clean and our progress uninhibited. We stopped under a grating adjacent to Dwinelle Hall to enjoy the fresh, cool air filtering down.

All at once there was this tremendous racket, a thunderous rumbling noise. ``The light!'' exclaimed Brandon. The beam revealed nothing unusual in either direction. Our hearts pounding, we saw a car drive overhead, over the grating. Now with an explanation as to the cause of the noise, we were much relieved, but it took some time for the adrenaline to wear off. The car had driven over large steel accessway up ahead in the tunnel, creating the noise. More excited than ever, we pressed onward.

Soon we encountered a T in the tunnel, branching to the right and left. We chose the left, carefully stepping over a hot steam pipe and a cooler return pipe. The tunnel was smaller than the main tunnel; we were increasingly aware that we were in an enclosed space with no nearby exit, with aging pipes carrying hot steam under high pressure -- which, of course, made it all the more exciting, yet we were aware of the danger.

This branch of the tunnel soon terminated at a secured grating. Peering upwards through it, we made out what we believed to be the eaves of California Hall, where the next day, disgruntled ethnic studies majors would launch a hunger strike. Brandon marked it on the map, and we reversed course. We intended to take the other branch of the fork, but hot water spurting from a joint in a pipe in that direction influenced our decision to see what lay in the other direction in the main tunnel -- we'll go back and explore that fork later.

Once past our original entry point and moving away from it, towards the steam plant, the tunnel sloped slightly downwards and angled slightly to the left. We encountered another grating where we paused briefly, enjoying the respite from the heat and stale air. Looking up into the moonlit sky through the welded-shut grating, a la Les Miserables, we watched a pedestrian walk overhead. Refreshed, we continued.

In this section, the tunnel lights were on, and the tunnel ahead seemed to be full of a dense fog. Before getting to the fog, we found a tunnel off to the right, which we took. This branch was much cooler than the main tunnel, which was refreshing -- but it was still hot. The lights were on, and the tunnel took several turns. Eventually we encountered a short staircase, and came up in a room full of machines with red and green lights, making whirring and churning noises -- in what could only be the basement of the Valley Life Sciences Building. We sat down in the dark to update our map. Behind Brandon lay a large tank, upon which I noticed a sign. I diverted the flashlight to read the sign: ``CAUTION: Hydrochloric Acid''. Yikes! What does anyone need with twenty five thousand liters of hydrochloric acid in the basement?

Finished updating the map, we got up to explore further. A resounding grinding noise flooded the room, resounding from one of the big machines. We nearly fell over in surprise. This machine emitted these bursts periodically for the duration of our visit, maybe every five minutes or so, each time disabling us with surprise.

On one side of the room, doors led to an open area, with a grating twelve or sixteen feet above us, leading to the secured bike-rack area between VLSB and VLSB-addition. We rested for a few minutes in this area, enjoying the relative quietude and the cool, fresh air from above. Also attached to this outdoor room, and North of the room with strange machines and caustic chemicals, lay an electrical room; the buzz of transformer emanated from the door, and peering through the slats in the door revealed a 20,000 volt conduit. All of the doors into the electrical room were locked.

A hole in the wall of the machine room revealed what might be described as a ``crawl space'' of vast proportions, with a 6 or 8 foot ceiling. My remark: ``And they say we have a housing crisis?!'' Brandon called it a ``foundation room.'' Signs indicated such things as the direction to ``SF 25 Filters''. (Although meaningless to us at the time, we later learned that ``SF'' stands for ``Supply Fan'' and ``EF'' stands for ``Exhaust Fan''.) We walked under the electrical room, the buzz and more twenty thousand volt conduits indicating its presence.

Walking back into the machine room, we found an ``EXIT'' door, leading to stairs up to a door into VLSB -- with an alarm. We noted it on the map, and noted the room numbers we could see across the hallway. A clipboard attached to the inside of the door noted, ``door found unlocked on these days:'' with dates penciled in. Apparently, ``they'' are quite security conscious.

Back in the machine room, we discovered another tank, equal in size to the HCl tank, this one bearing the notice: ``SODIUM HYDROXIDE''. These tanks dismayed me far more than the high-pressure steam pipes. HCl burns, and NaOH dissolves the lipid molecules that hold people together. Fun stuff.

Having sufficiently explored this VLSB basement, we went back into the steam tunnels, retracing our steps to the branch in the main tunnel. Re-entering the main tunnel was like penetrating a wall of heat. We turned right, heading once again towards the steam plant. Ahead, the tunnel sloped down. We would later discover that the steam tunnel was actually traveling through the Cross Campus Road bridge over Strawberry Creek, South Fork. The temperature and moisture was almost unbearable. Throttles in the steam pipes created a tremendous noise. Ahead, the lights of the tunnel disappeared into opaque fog. We pressed onwards. Finally, we reached a latched gate. Aha! probably the entrance to the steam plant, which is in all likelihood the hub of the tunnels, our gateway to evermore locations on campus. Satisfied with our discoveries, weary from the unrelenting heat, humidity, and noise, we decided to call it a night -- we turned around and headed East, towards the Entry Point.

Once sufficiently far away from the noise of the throttles, I remarked to Brandon: ``this is why I do not live in Florida,'' referring to the environmental conditions in the tunnels. Once at the entry point, Brandon swung the grating open, sprang out, closed the grating, and ran off. I stood perched on the ladder, wondering about the situation topside. Sure enough, soon Brandon came back and opened the grating for me, explaining: ``when I came out, I saw headlights up ahead.'' Back in the terrestrial world, we retraced our steps on the surface, figuring out the lay of the tunnels we'd explored, and found a new entry point to explore next time.

``Where is the steam tunnel culture here? This is Berkeley! You would think that, of all places, there would be a culture here,'' I pondered verbally to Brandon.

``I don't know. But that's only one way in which Berkeley isn't what it seems. I guess they're just into other things. Protests.'' Brandon speculated.

``I suppose, then, that it's up to us.''

``Yes. There is a lot we need to do here before we leave.''


Date: Thu, 13 May 1999 20:50:14 -0700
From: Cliff Stoll 
To: Tobin Fricke
Subject: Re: Steam Tunnels

>Hello Cliff,
>I was reading through the archives of alt.college.tunnels and I came
>across a post by you.  I was wondering if you made any forrays into the
>underground during your time here at Cal.  I've discovered the main steam
>tunnel leading up Cross Campus Way and under Wheeler Hall, and am looking
>for other tunnels, and like minded individuals.  Incidently, I very much
>enjoyed your book.

Hi Tobin,

Yow!  I'm amazed -- that posting must be ancient.  I've only once been
in the UCB steam tunnels, and that was legally (we were checking out
paths for some ethernet links way back in 1989).  Most of tunnelling
was at the State Univ. of NY at Buffalo ... long ago, before all the
tunnels were alarmed.

Date: Tue, 16 Jan 2001 16:58:21 -0600
From: anonymous coward
To: tobin@splorg.org
Subject: UnderCal web site

Cool site!

BTW, I don't know about doco, but Cal definitely has had a strong
old-school hacker community going back a long ways. I did the steam-tunnel
tour in my first *week* there in 1981. It just was the thing to do in our
hall back then. I suppose that no one wrote much down because everyone
knew, and, more importantly, doco was evidence that we were doing
something very non-honors-society.

Date: Tue, 16 Jan 2001 09:32:53 -0800 (PST)
From: Erik 
To: tobin@splorg.org
Subject: Those old steam tunnels

I just read an article on Salon.com about
those-who-explore-old-tunnels, and I couldn't help looking around for info
on UCB's steam tunnels.  A link on the Urban Explorers Network led me to
UnderCal, which, of course, led me to you.

My friends and I explored the steam tunnels around 1991-92.  At that time,
the Life Sciences Building was closed for renovations, but we discovered
that we could get in through the tunnels.  The building looked like
something out of a post-apocalyptic movie-- a frame of a building, looking
bombed-out, lacking most interior walls, with a huge courtyard-like space
in the center.  We used to climb the stairs to  the roof and watch the
cops drive by on patrol.
Following the tunnels east took us to the basement of a building somewhere
near the RSF, filled with what looked like temperature-regulating
equipment.  As it was rather well-lit, we hoofed it back into the tunnels.

We also found ways into California and Wheeler, but Doe eluded us.  Also,
near Durant there was a room filled with about three feet of water-- we
gave that a pass.

Anywho, it's great to see that someone has been carrying on the
tradition.  Good luck, and happy tunneling.


From: Casey
Date: Sat, 7 Apr 2001 16:42:57 -0700 (PDT)

Hi Tobin,
    your website was actually what prompted me to try out the steam tunnels.
It was one of the only local UE sites, and the only site (that I remember)
that mentioned the steam tunnels under UCB. As far as my exploits in
Berkeley, I discovered a (probably) previously unexplored section of steam
tunnel. Unfortunately, the only reason that I say that it probably hasn't be
explored is because it's about 50 meters long and goes nowhere. Other then
that, I went down the steam tunnels mentioned in your website. I found the
entrances by using the map on your website and the description of the
journey. I also found another entrance, a locked grate to the right the
Physical Services plant that can be picked. If you're interested in the
place that I found, it's around the back of the building with the cast iron
pelican on the lawn. I nicknamed it Pelican's Perch, because the tunnel goes
directly under the statue. It's probably not worth you're while though, as
it's pretty tiny. But then again, the grates always unlocked, and the tunnel
is fully lit.

PS Thanks so much for putting up your website. It was really useful to have
a local resource for UE info.
Date: Sat, 07 Apr 2001 22:54:33 -0700
From: Casey 
To: Tobin Fricke 
Subject: Re: Seattle WA

Dear Tobin,
    if you're interested in finding more to explore on UCB campus, there is
one thing which I couldn't check out, but that I'm pretty sure is bona fide.
Near the Hearst Mining Building (Now undergoing renovation) there is
supposed to be an actual stretch of mining tunnel, complete with mine car
tracks and a mine car. Here's the address of the website where I found out
about it. Attached to this email is also a good picture of the mine.
Unfortunately when a friend and I went to the hearst mining building, it had
been raining, and due to the construction, there was a lake sized puddle
directly in front of what I believe to be the entrance.

Anyways, about my own minor discovery. Nope, it sure doesn't connect to
anything. It is a pretty neat tunnel. I don't know how much of a nerd you
are, but when I saw the grate I was immediately reminded of Zork. Don't know
why, probably the locked grate in the woods. Anyways, if you go at night,
and the lights in the tunnel are on, it's really very pretty. In a shadowy
corner of the building it's just a grate pouring out light. Ahhh...
Ahem, other then that it's not too spectacular. There are working lights
along the whole length that are operated by a switch down a little ways and
on the left side after you enter. The tunnel gets hotter and more humid the
farther you progress down it, and there are small puddles at the end.

    Happy Vadding,

Date: Mon, 30 Dec 2002 17:37:34 +0100
From: Michael Binzer 
To: tobin@splorg.org
Subject: those expeditions...

Hi Tobin,

BTW I from germany and my english is not very well, so dont be amazed about my mistakes...

I found a link to your website by searing facts about Linus Torvalds, which was about a meeting with him. I looked aroung at the root-directory and found the link to your other projects. All of them were interesting but one was especielly: the steam tunnel project.

Wow, its very cool, i thought. last summer something like that happend to me, too:

many years ago in the 60s and the 70s a beer factory was at m city. then in the early 90s it became insolvent. it was a very great builnding, but only a little part was pulled down. the area was closed and nobody used this area, only a small buliding of the "department of order" [they r something like the police but they wear civil clothes.

Now, 10 years later, some of my freinds and i found these buldings and the area. now i want to describe what we found out: We only entered the buldings at night or at sunrise, when the civil-police-department was closed.

There are two ways to get into: 1. the stupid way -climbing over the fence- because of the cameras many of ignorant kids were captured by the police. 2. the heavy-brainablated-crazy-most stupid-way- you had to walk through a path, there are often aggressive dogs. Then you come to bulding, it might be the 'holiday-house' of thw owner. Its full of plants and grass. You had to climb along a swimming pool and now you've got a great view over the whole area. Beside yourself there are big pipes. U stand on a wall, about 15 meters over the floor. Now you have to balance of a rotten trunk. If u fall, your neck will be broken :). If you passed this dangerous situations u'll have to jump on a hill of little stones -about 3 meters away. The trunk is still 10 meters over the floor. after this test -run! now you are able to enter the main bulding. There is a cafeteria it looks a bar after the ypocalyps. the ceiling brought down on the floor. but the greatest thingh is the celar. its 10 m! eter under the surface. U had to climb down by using a cable. its completly dark, but u can here some noises -very scary! sometimes u think somebody is behind u. at the deepest level u can find the big turbines, a rooms, which walls are full of cristals, even in summer at this room it under 10 degrees. We opened a strongroom but there were only some dociments inside. there are some albores too. [halflife *eekkk*] then you can go to the top of the bulding. the roof is broken. so you can walk over it. Its just cool, when u came out of the dark and then you have a great view over the city *sigh*

I hope a gave you a little piece of the feeling, which affects this beer factory...

greeting from germany, Your M. Binzer

there is a great area of woods and grass, its very hard to get through that vegetation.

From: John Peterson <jpeterson@wba-arch.com>
Date: Tue, 4 May 2004 15:24:00 -0400
Subject: Steam tunnels

Saw your website on a search for steam tunnels and found the article by the joker that claims they were originally used as a means of transportation between buildings.Tunnels like those you explored have been there solely to transport and maintain the steam systems for the buildings. They are dangerous and I have even seen a man's hardhat melted on the top of his head when he tried to sprint under a leak in Washington DC. If water gets into the steam piping it will act as a hammer on the system, tearing pipes from the walls and thrashing them about like plastic straws.

Have fun, but be aware that every time you visit you are taking a risk.


John Peterson
Mechanical Engineer
LEED Accredited Professional
44 Canal Center Plaza
Suite 100
Alexandria, VA 22314

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