# Why is the Chicago El elevated? **URL:** \ **Category:** Factual Questions\ **Created:** [December 12, 2011, 4:05pm UTC](https://boards.straightdope.com/t/why-is-the-chicago-el-elevated/605916 "2011-12-12T16:05:52Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![wittysobriquet](https://avatars.discourse-cdn.com/v4/letter/w/e95f7d/32.png) [@wittysobriquet](https://boards.straightdope.com/u/wittysobriquet)\ **Post date:** [December 12, 2011, 4:05pm UTC](https://boards.straightdope.com/t/why-is-the-chicago-el-elevated/605916/1 "2011-12-12T16:05:52Z")
My (admittedly pretty weak) Googlage has been fruitless. Why are the choo-choos upstairs instead of in the basement? ---
**Author:** ![constanze](https://avatars.discourse-cdn.com/v4/letter/c/f9ae1b/32.png) [@constanze](https://boards.straightdope.com/u/constanze)\ **Post date:** [December 12, 2011, 4:15pm UTC](https://boards.straightdope.com/t/why-is-the-chicago-el-elevated/605916/2 "2011-12-12T16:15:07Z")
Cost? Running a train above ground is cheaper than digging a tunnel. It could also depend on how good the technology to build a tunnel was at the time when it was built. ---
**Author:** ![wittysobriquet](https://avatars.discourse-cdn.com/v4/letter/w/e95f7d/32.png) [@wittysobriquet](https://boards.straightdope.com/u/wittysobriquet)\ **Post date:** [December 12, 2011, 4:20pm UTC](https://boards.straightdope.com/t/why-is-the-chicago-el-elevated/605916/3 "2011-12-12T16:20:40Z")
> [@constanze](#): > > Cost? Running a train above ground is cheaper than digging a tunnel. But is it? Is steel above ground cheaper than building a hole? > [@constanze](#): > > It could also depend on how good the technology to build a tunnel was at the time when it was built. The Boston “T” built their subways (1897) before their elevated railways (1901). So the tech was, I’m guessing, available in 1892 when the El began. ---
**Author:** ![Great\_Antibob](https://avatars.discourse-cdn.com/v4/letter/g/e47c2d/32.png) [@Great\_Antibob](https://boards.straightdope.com/u/Great_Antibob)\ **Post date:** [December 12, 2011, 4:29pm UTC](https://boards.straightdope.com/t/why-is-the-chicago-el-elevated/605916/4 "2011-12-12T16:29:58Z")
Doesn’t Chicago have a very high water table? And pretty much only dirt under the ground? This is the same reason skyscrapers were harder to build in Chicago than New York. I’m not sure the technology actually did exist in the 1890s, or if so, that it was cost-effective compared to a Boston or New York. ---
**Author:** ![spifflog](https://avatars.discourse-cdn.com/v4/letter/s/c5a1d2/32.png) [@spifflog](https://boards.straightdope.com/u/spifflog)\ **Post date:** [December 12, 2011, 4:30pm UTC](https://boards.straightdope.com/t/why-is-the-chicago-el-elevated/605916/5 "2011-12-12T16:30:18Z")
It’s called the El. You can’t call it that and then bury it! :dubious: 😃 ---
**Author:** ![Musicat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/musicat/32/20189_2.png) [@Musicat](https://boards.straightdope.com/u/Musicat)\ **Post date:** [December 12, 2011, 4:30pm UTC](https://boards.straightdope.com/t/why-is-the-chicago-el-elevated/605916/6 "2011-12-12T16:30:51Z")
Underground can be expensive. Here’s an example of some of the problems encountered at the [Manhattan 2nd Ave subway:](http://en.wikipedia.org/wiki/Second_Avenue_Subway) > [@](#): > > The tunnels and stations will be up to approximately 30 meters (98 ft) below street level. Of the below-ground obstacles, Arup director of construction David Caiden says: “It’s a spaghetti of tunnels, utilities, pipes and cables – I’ve never seen anything like it.” Additionally, the project must go over, or under, subway lines, Amtrak railway lines, and the Queens-Midtown Tunnel linking Manhattan and Queens. > > There are geological anomalies along the way. Manhattan’s geology changes along the subway’s length, passing through rock and soft ground, consisting of sands, silts, and clays over Manhattan schist, and there are faults and shear zones as well as fractured rock. Hard-rock Tunnel Boring Machines 6.7 meters (22 ft) in diameter will tunnel during the first phase, progressing at anticipated rate of about 20 meters (66 ft) per day. At least for overhead construction, you can see what it is the way. Underground, not so much. ---
**Author:** ![gotpasswords](https://avatars.discourse-cdn.com/v4/letter/g/c57346/32.png) [@gotpasswords](https://boards.straightdope.com/u/gotpasswords)\ **Post date:** [December 12, 2011, 4:34pm UTC](https://boards.straightdope.com/t/why-is-the-chicago-el-elevated/605916/7 "2011-12-12T16:34:14Z")
The water table in downtown Chicago is pretty high, which greatly complicates tunneling. A few years ago, basements in many Loop buildings were flooded after some bridge piling maintenance cracked a service tunnel. I don’t think engineers had figured out underwater tunneling 120 years ago. Also, the El is seriously old -it started operation in 1892 or so with steam locomotives, and steam locks and tunnels are not a good mix unless you intend to asphyxiate your passengers. ---
**Author:** ![Skammer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/skammer/32/143_2.png) [@Skammer](https://boards.straightdope.com/u/Skammer)\ **Post date:** [December 12, 2011, 4:38pm UTC](https://boards.straightdope.com/t/why-is-the-chicago-el-elevated/605916/8 "2011-12-12T16:38:46Z")
Chicago has a subway - the Red Line. So any problems with the geology or water table or steam power were apparently solveable by the time it was built. However I wouldn’t be surprised to learn if it was built much later than the El. ---
**Author:** ![pulykamell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pulykamell/32/3166_2.png) [@pulykamell](https://boards.straightdope.com/u/pulykamell)\ **Post date:** [December 12, 2011, 4:50pm UTC](https://boards.straightdope.com/t/why-is-the-chicago-el-elevated/605916/9 "2011-12-12T16:50:09Z")
> [@Skammer](#): > > Chicago has a subway - the Red Line. So any problems with the geology or water table or steam power were apparently solveable by the time it was built. However I wouldn’t be surprised to learn if it was built much later than the El. Also, parts of the Blue Line. (And it’s only parts of the Red Line, as well). And, also, the colored line names and routes are all fairly new (early 90s, I think, is when the lines became known by their colors.) [The history of the Chicago subway can be found here](http://www.chicago-l.org/history/unification.html). Ground was broken in 1938. The State Street tunnel opened in 1943, and the Dearborn Tunnel in 1951. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [December 12, 2011, 4:55pm UTC](https://boards.straightdope.com/t/why-is-the-chicago-el-elevated/605916/10 "2011-12-12T16:55:08Z")
> [@wittysobriquet](#): > > But is it? Is steel above ground cheaper than building a hole? Generally, yes. In the New York system, it’s mainly the lines in Manhattan and Brooklyn, where population is densest, where the lines are underground. Lines in the outer boroughs, especially towards the ends of the lines, are mainly above ground, either elevated or sometimes at ground level. ---
**Author:** ![wittysobriquet](https://avatars.discourse-cdn.com/v4/letter/w/e95f7d/32.png) [@wittysobriquet](https://boards.straightdope.com/u/wittysobriquet)\ **Post date:** [December 12, 2011, 5:05pm UTC](https://boards.straightdope.com/t/why-is-the-chicago-el-elevated/605916/11 "2011-12-12T17:05:19Z")
All good points, and thanks for the replies! But, does anyone know why they built it that way? I mean, according to the engineers of the project at the time? Both ways have plusses and minuses, but it seems that most of most other systems are subways. Wondering if there’s some kind of, like, documentary evidence about why the El was chosen in Chicago. I know in NYC, steam trains prevented the use of subways until electric trains came along, at which point much of the trains were put underground. But that didn’t seem to happen here. Was it just a matter of inertia - leaving well enough alone? An artifact from the steam age? ---
**Author:** ![friedo](https://avatars.discourse-cdn.com/v4/letter/f/8edcca/32.png) [@friedo](https://boards.straightdope.com/u/friedo)\ **Post date:** [December 12, 2011, 5:10pm UTC](https://boards.straightdope.com/t/why-is-the-chicago-el-elevated/605916/12 "2011-12-12T17:10:52Z")
> [@Colibri](#): > > Generally, yes. In the New York system, it’s mainly the lines in Manhattan and Brooklyn, where population is densest, where the lines are underground. Lines in the outer boroughs, especially towards the ends of the lines, are mainly above ground, either elevated or sometimes at ground level. The Brighton Line in Brooklyn is mostly open-cut once you get out of downtown. Sucks when it snows. As for other lines, the Flushing Line is elevated from the Queens side of the Steinway tunnel all the way to Shea Stadium, the Astoria Line is elevated for its entire length, the Canarsie Line is elevated between downtown Brooklyn and New Lots, and the northern ends of much of the IRT lines are elevated in the Bronx. And interesting exception is the massive Queens Boulevard trunk, which is underground for all of its run in Queens and Manhattan, despite running amongst some of the lesser populated areas of the city. ---
**Author:** ![Kent\_Clark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kent_clark/32/105_2.png) [@Kent\_Clark](https://boards.straightdope.com/u/Kent_Clark)\ **Post date:** [December 12, 2011, 5:18pm UTC](https://boards.straightdope.com/t/why-is-the-chicago-el-elevated/605916/13 "2011-12-12T17:18:44Z")
Going backl even further in \*\*pulykamell’s \*\*[timeline](http://www.chicago-l.org/history/4line.html), the original lines were built as elevated lines using steam locomotives. This started in 1869. At some points, the transit companies were building lines in the alleys (which were owned by and under the control of the city), because they couldn’t get property owners’ permission to build on the streets. Looks like engineering might not have been the only problem with digging big holes in the center of town. ---
**Author:** ![Tastes\_of\_Chocolate](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tastes_of_chocolate/32/3232_2.png) [@Tastes\_of\_Chocolate](https://boards.straightdope.com/u/Tastes_of_Chocolate)\ **Post date:** [December 12, 2011, 5:21pm UTC](https://boards.straightdope.com/t/why-is-the-chicago-el-elevated/605916/14 "2011-12-12T17:21:01Z")
Actually, Chicago has one line that has underground, at grade and elevated sections, all on the same line. The Blue Line runs from O’Hare Airport to downtown and then west to Forest Park [Chicago Blue line](http://en.wikipedia.org/wiki/Blue_Line_(Chicago_Transit_Authority)) ---
**Author:** ![Svejk\_1](https://avatars.discourse-cdn.com/v4/letter/s/ea666f/32.png) [@Svejk\_1](https://boards.straightdope.com/u/Svejk_1)\ **Post date:** [December 12, 2011, 5:27pm UTC](https://boards.straightdope.com/t/why-is-the-chicago-el-elevated/605916/15 "2011-12-12T17:27:11Z")
To add to Colibri’s point, the New York Subway system used to rely much more heavily on elevated trains. A lot of them are now[defunct](http://en.wikipedia.org/wiki/List_of_New_York_City_Subway_lines#Defunct_lines) and have been demolished though, presumably as a result of better technology coming along. At any rate, it would seem that it’s not the case that around 1900 or so Chicago was building elevated trains when all sorts of other cities were building underground systems. ---
**Author:** ![wittysobriquet](https://avatars.discourse-cdn.com/v4/letter/w/e95f7d/32.png) [@wittysobriquet](https://boards.straightdope.com/u/wittysobriquet)\ **Post date:** [December 12, 2011, 5:35pm UTC](https://boards.straightdope.com/t/why-is-the-chicago-el-elevated/605916/16 "2011-12-12T17:35:30Z")
> [@Svejk\_1](#): > > At any rate, it would seem that it’s not the case that around 1900 or so Chicago was building elevated trains when all sorts of other cities were building underground systems. But (not to be a broken record) why? ---
**Author:** ![wittysobriquet](https://avatars.discourse-cdn.com/v4/letter/w/e95f7d/32.png) [@wittysobriquet](https://boards.straightdope.com/u/wittysobriquet)\ **Post date:** [December 12, 2011, 5:43pm UTC](https://boards.straightdope.com/t/why-is-the-chicago-el-elevated/605916/17 "2011-12-12T17:43:09Z")
Oops. Just saw that “not.” Skip the previous. ---
**Author:** ![Dead\_Cat](https://avatars.discourse-cdn.com/v4/letter/d/9fc29f/32.png) [@Dead\_Cat](https://boards.straightdope.com/u/Dead_Cat)\ **Post date:** [December 12, 2011, 5:50pm UTC](https://boards.straightdope.com/t/why-is-the-chicago-el-elevated/605916/18 "2011-12-12T17:50:46Z")
I don’t know the answer, but all those hypothesising that underground/underwater railways were not feasible in the 1890s may wish to note that the first London Underground railway opened in 1863, and the Severn Tunnel (which runs for 4 miles under one of Britain’s largest estuaries) was constructed between 1873 and 1886 - Wikipedia has more details, of course. So those mentioning geological conditions peculiar to Chicago would seem to be more on the right (heh) track. ---
**Author:** ![Spoke](https://avatars.discourse-cdn.com/v4/letter/s/a88e57/32.png) [@Spoke](https://boards.straightdope.com/u/Spoke)\ **Post date:** [December 12, 2011, 5:55pm UTC](https://boards.straightdope.com/t/why-is-the-chicago-el-elevated/605916/19 "2011-12-12T17:55:24Z")
I seem to recall that [The Devil in the White City](http://en.wikipedia.org/wiki/The_Devil_in_the_White_City) went into some detail about Chicago’s sandy, saturated soil (as contrasted with New York’s close-to-the-surface bedrock). ---
**Author:** ![Skammer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/skammer/32/143_2.png) [@Skammer](https://boards.straightdope.com/u/Skammer)\ **Post date:** [December 12, 2011, 5:57pm UTC](https://boards.straightdope.com/t/why-is-the-chicago-el-elevated/605916/20 "2011-12-12T17:57:42Z")
> [@pulykamell](#): > > Also, parts of the Blue Line. (And it’s only parts of the Red Line, as well). And, also, the colored line names and routes are all fairly new (early 90s, I think, is when the lines became known by their colors.) Formally, perhaps, but when I attended Northwestern in the late 80’s they were usually referred to by color even though the official names were “Evanston Express” or “Ravenswood” or whatever. I guess they finally gave up and went with the color names since that’s what everyone used anyway. [Next page](https://boards.straightdope.com/t/why-is-the-chicago-el-elevated/605916.md?page=2)