I’ve been wondering about this for years. In the movies, such as Teenage Mutant Ninja Turtles and Ghostbusters 2, some of the characters walked around in sewers. I was wondering how large of cities have sewers and storm drains where you can actually walk from one manhole to another underground. When I was a kid, I looked in one of the manholes in my hometown of Beckville (population 762) and it was just a hole with roughly a 4 inch pipe on each side. That was disappointing to say the least. Of course now I’m old enough to know that such a small town obviously wouldn’t have an explorable sewer system, but what about smaller cities? Do they just have holes in the ground with larger pipes or do they have tunnels and stuff? Or is that only found in the metropolis cities? If I accidentally fall into a puddle of mutagen, I need to know where to go hang out.
Sewer pipes can vary from 1.5" (for a small force drain) to 36" or more for a major outlet storm sewer. As a boy, I used to go exploring with some friends through a storm outlet near the home of a friend, in search of dinosaurs. (Well, I was a kid!) As I recall the sewers were about 30" diameter.
(We never found any dinosaurs, unfortunately.)
You can take a sewer tour of Paris - they’re famous. I’ve never been, but it’s like the sewers you see in movies, you know, beautiful stonework, huge tunnels, etc. Can’t speak to other cities.
I suggest you do a search on “infiltration explorer buildings sewers” in different combinations. You can find pictures of where people have been.
There are big storm sewers underneath Detroit. You can walk upright in them. There’s a narrow ditch in the middle where small amounts of water drain when it’s not raining, so you have to walk sort of spraddle-footed. A girl named Linda took me through an entrance where the water emptied out into a lake and showed me through those sewers one night, a long time ago…
“Michigan seems like a dream to me now…”
My college in upstate New York had extensive tunnels to deliver steam heat through the campus, and some students explored those. If you google the subject, you’ll find that it wasn’t done just at my school.
Large storm sewers can be found in many towns. In mine the kids had made out an “adventurers map” that showed them all, showed how large they were, where the manholes and entrances were, etc. A few of them had small but odd underground rooms, one I was personally in was large enough for 7 or 8 people, and even in retrospect seemed to serve no real purpose.
A local shopping mall nearby has a drain large enough to safely drive a small car into.
I have not figured out the Google™ mojo to show the relationship betwen sewer size and city size. (I know the metro areas larger than 1,000,000 people are quite likely to have sanitary sewers that are over 84" in diameter (a few much larger) or the newer square crossform sewers that are even larger, but I cannot find a chart or list that shows sewer sizes dropping with population.) On the other hand, I have found a few cases of anecdotal evidence for moderately large sewers in rather small towns. For example, Herriman UT (pop. 1500) had a plastic sewer line ignited by kids building a fort and the sewer had a 42" diameter.
'Have them in Dallas.
I reckon that maximum sewer size might be more a function of the number of houses/businesses and their expected effluent versus the number of sewage treatment plants. And the age of the city as well…
Maximum sewer size for carrier or interceptor lines has way more to do with the population served and the grade within a particular area. Sewer design, in part, is based on a per capita flow per person for the area being served. By definition, “sewers” are gravity flow conduits which must also take into account such factors as “inflow and infiltration” (I&I) and most Metro areas have large (greater than 54-inches in diameter) sewer lines. In some cities, like New York, the competition for available (elevation or depth) space finds City utility lines 800 to 900 below ground level. Since most of NYC drinking water comes from reservoirs in upstate New York and these are gravity lines the depth below ground level in the City can get staggering.
I know about the Paris ones. Victor Hugo devoted an entire chapter to the Paris Sewer System(Circa 1832) in Les Miserables.
Unfortunatly, ever since then I’ve always hated the sewers in the movie versions. They always seemed too clean and well lit.
I’ve been on the Paris Sewer tour, sort of. They were mostly closed *when I went but were selling the “tour” at the same price (of course, it is France) and all you got to see were a couple of large rooms of “artifacts” found and a display with a diorama or three. No actual sewers.
- You know, like when you go to the Louvre and find out so many people are on strike that 2/3 of the museum is cordoned off with velvet ropes and guards…
When my dad was a teen he found a good sized one of those under Nimitz Hwy in Honolulu. They brought some down some old chairs and couches into and had parties there. This would have been back in the 60s. Then a big rain storm came and washed everything away. Luckily no one was there at the time but still, word of note, those places can be very dangerous.
Aren’t you talking about sanitary sewers?
All of the sewers I’ve ever explored were storm sewers, a completely separate system from sanitary sewers.
And don’t be fooled by the name, sanitary sewers are very very dirty
Some small town’s have large drainage systems to handle peek water drainage, because it’s a yearly water threat. Wisconsin Dells used a cave system originally and it’s still part of the system. Some building used caves accessed through their sub-basements for storage. There’s a salt company that dug out salt from a lower level with some tunnels only a couple feet square, under the neighborhood.
Paris tunnels include chalk mines, caves, sewers, catacombs, and war installations. The people that took pictures of these adventures, have gone where only a skinny person who’s never been a touch scared of the pitch dark, tight places, or vast depths could go.
If you google “urban exploration” you will find several websites devoted to infiltrating and documenting not only sewers, but abandoned buildings, old subway tunnels, and so on.
Great sewer chases in films include “The Third Man,” filmed in late 40s Vienna, and “The Italian Job” (though I’ve only seen stills of the latter).
I can tell you from first-hand experience this is true.
I can also tell you (from first-hand experience) that if you get caught you will get in BIG trouble. By the way, you will get caught. Steam tunnels are booby trapped with silent alarms, and the campus police are generally not happy about having to go down there to fish you out.
Most of SF’s lines are pear-shaped in cross-section - it’s a fairly efficient, if cramped, shape for a person to walk through. Here’s a scan fron 1875 showing the shape.
A recent episode of Dirty Jobs featured SF sewers. They were portrayed as cramped, claustrophobic spaces with plenty of running nasties - sewage, bugs and rodents. Certainly explorable, but* yeesh!* who’d want to?