CTA "L" Curves and Jogs

[chicagopcclcar]

The north side main jogs through the diagonal property lines at North Clack St.

With the CTA's plans for the Brown Line Bypass, some attention has come to the many curves and jogs in the CTA "L". The northside "L" structure from Graceland (Irving Park) to Willow Sts. basically follows the alley east of Sheffield Ave. This almost three mile stretch has more kinks, shifts, jogs, than anywhere else on the city's "L"...... especially north of Diversey because the tracks constantly adjust to the alley location and constantly adjust to varied property lines when the alleys are perpendicular. Plus, throw in the lot lines aligned to the diagonal Clark St. near Roscoe.

Unlike East Coast cities.... New York, Boston, Philadelphia were most lines were over the streets; three of the four elevated railroads chartered and constructed in Chicago; The South Side, The Metropolitan West Side, and The Northwestern were required by their franchise ordinances to only build "through the blocks." They could buy, lease, rent, a private right of way, but they could not build over streets or alleys. They could cross them, of course.

If the half block streets and their accompanying alleys parallel the route, the cheapest way to go was to usually buy the back 25 ft of backyards next to the alley. The northside "L" needed 50 ft. to accommodate the four track mainline. If the alleys were perpendicular to the elevated, a more expensive purchase of entire lots was needed and the lots had to all be in a row. Usually the "L" selected lots at the quarter points of the block so that if the next subdivision was oriented at right angles, the "L" easily slid across the boundary already positioned next to the alley.

The Northwestern laid out a four track main line, featuring express and local tracks patterned after New York City. The entire structure used tower bents, which by 1900 had become the standard engineering style...... North Main, Ravenswood, Engelewood, Stockyards, Kenwood yard only. But making room for the Northwestern's four track elevated at the rear of lots left little room for buildings on the remainder of the lot.

Between Diversey and Wellington the alleys run east-west. The "L" had to line up the property lines before resuming its path north. Again property lines declared the limits of the right-of-way when the "L" crossed the diagonal Clark St. The final block before the right angle turn at Sheridan Rd. finds the alley and street running east and west....the ''L" makes a correction and turns to line up with the old Milwaukee Road railroad.

In the old days the "L" motormen only shut off while running through some jogs. Air brakes stayed at release. Even the PCC 6000s could coast through. Even the jogs near Diversey; in the middle of a good speed run where they could get to 45 mph with motors humming, LOL. But the high performance cars with their 55 mph was too fast, so the signals had to be cut and 35 mph was the only indication available. That meant a 2nd point brake application.

In Chicago, the only exception to the "build through the blocks" was the politically connected Lake Street Elevated. The charter specified "build along and upon" and the elevated was constructed using the street as a right of way and no signatures were ever solicited. But neither the city nor the railroad was bold enough to build east of Market St. so proper signatures were gathered and the over the street elevated won a charter east as far as Wabash Ave.

A SB Purple line train encounters the street alignments near Sheridan.

The crowd at Sheridan is waiting for a charter train.

[strictures]

Sorry, but according to one of Carl Condit's books on Chicago architecture, the reason for the alley L tracks in Chicago was the disgust of the property owners on Wabash, who hated the L over the street.

So a law was passed in the General Assembly, I believe in 1904, but possibly before the Metropolitan System was built, that banned building tracks over any street, without the permission of a majority of the adjacent landowners.

The Northwestern Elevated Rail was built in 1906-07 & was forced to use the alleys, thus all the jogs. I've seen photos of the Sheridan S turn under construction & there's not a building in sight in 1906.

[chicagopcclcar]

Sorry, but according to one of Carl Condit's books on Chicago architecture, the reason for the alley L tracks in Chicago was the disgust of the property owners on Wabash, who hated the L over the street.

So a law was passed in the General Assembly, I believe in 1904, but possibly before the Metropolitan System was built, that banned building tracks over any street, without the permission of a majority of the adjacent landowners.

The Northwestern Elevated Rail was built in 1906-07 & was forced to use the alleys, thus all the jogs. I've seen photos of the Sheridan S turn under construction & there's not a building in sight in 1906.

The Alley "L" was built in 1892. The Metropolitan was opened by 1895. True, Sheridan was built through vacant land, but the Northwestern opened in 1900. The Southside had a changed charter that permitted the line over E. 63rd St. and the entrance to the Columbian World's Fair. The line opened in 1893. I don't find any of your dates correct.

[chicagopcclcar]

Six companies built Chicago's original "L". Two were only associated with building the downtown elevated. We started with the fourth, the Northwestern, because the interest in the Clark Junction. In the last decade of 1890 the Northwestern Elevated could build and build, until they reached the city limits. Just do it all on private land. The Northwestern laid out a four track main line, featuring express and local tracks patterned after New York City. Because of the interest of the bypass at Clark Junction, we looked at the "L" north of Diversey because the tracks constantly jog and curve adjust to the alley location. Not to be overlooked, are other Northwestern highlights like the curves near North Ave. and Halsted St., long rumored to be caused by property owners who demanded too much money and the "church curves" where the Northwestern swung its right of way around St. Joseph's Church, just south of Division. While it was the last "L" built, the Northwestern it has kept its original structure. From Chicago to Wilson, it has five 90 degree turns...two at Sheridan, two at North Ave., one at Sedgwick; lesser curves like Montrose, two along Clybourn, the Church Curves at Division. No other elevated sports such cuvrature in track degrees.

In the first installment, we mentioned how Chicago's "L"s got next to alleys or on private property, unlike the East cities where their els are almost all over streets. Chicago over-the-streets will be talked about later.......Lake Street and the Loop "L".

The South Side R. T. "L" got the "official" name first. The name "Alley 'L'" has many origins depending on who's telling the story. Some say the name is because the route was built over the alleys. Wrong! It was built next to the alley. The Alley 'L' actually had the name before the first steel beam was raised. In 1888 there was a second company that preceded the South Side R.T., the Consolidated Rapid Transit & Elevated Railroad and they said they had enough signed consents to comply with state law to build an elevated railroad over south State St. from downtown to the city limits. They also had an ordinance from the Town of Hyde Park, south of 39th St., specifying a right of way along the alley east of Prairie Ave. from 43rd to 63rd; then east to St. Lawrence and south to 83rd St. where the line would split with one branch going all the way to South Chicago. Proponents and supporters of each elevated proposal witnessed a Chicago style brawl in the city council and in the courts over petition signatures that came to be known as the "State St.'L' road" versus the "alley 'L' road". Thus the name was coined identifying the comparison between the two, just as much as the location of the latter. It's not necessary to ask, "Who won?"

Two state laws figured in where the "L" were located....the Cities and Villages of 1872 and the "Adams Law ". The laws said that property owners had to give their 51 percent to permit the "L" build over the streets. Without that, three of the four elevated railroads chartered and constructed in Chicago; The South Side, The Metropolitan West Side, and The Northwestern were required by their franchise ordinances to only build "through the blocks." They could buy, lease, rent, a private right of way, but they could not build over streets or alleys. They could cross them, of course. If the half block streets and their accompanying alleys parallel the route, the cheapest way to go was to usually buy the back 25 ft of backyards next to the alley. If the alleys were perpendicular to the elevated, a more expensive purchase of entire lots was needed and the lots had to all be in a row. Usually the "L" selected lots at the quarter points so that if the next subdivision was oriented at right angles, the "L" easily slid across the boundary already positioned next to the alley.

The first "L", the South Side R. T. broke ground next to the alley at 25th St., just east of State St. The right of way for the most part was straightforward, north and south with small jogs where alleys jogged like at 18th, 21st, 25th, 26th, 35th, 37th, and 39th.... strung out on the west side of the alley, except in between 14th and 12th Sts. where the line crossed to the east side of the alley.

Although the franchise stipulated that 39th St. was the end terminal, before the tracks reached that point the Jackson Park Worlds Fair site was selected as the new end point. 39th St. was the city limits when the original charter was granted, but the new city limits had leaped to 138th St. in one fell swoop. The South Side chose the alley east of Prairie Ave. probably because the alley east of State was built up almost all the way to 63rd whereas the Prairie alley south from 44th St. was mostly vacant. Plus to go behind State St. would encounter two large cable car buildings.

Trivia question......most south side section street are odd numbers. Why the city limits a even street....East 138th St.?

The "L" crosses from the west side to the east side of the alley in the 4800 south block. My thinking is they did that to avoid jogs to match up with shifts in the alley locations south from that point. Between 51st St. and 56th St., there is no alley. The east orientation also made the 61st St. yard a simple fit. Only one jog was needed to match a shift in the alley....at 57th and 58th Sts. A half block center track just north of the only island platform was put in at 58th St. Approved branches south to 71st and west into Englewood would have to wait, the first goal was getting the line to Jackson Park and the charter specified building through the blocks anywhere between 60th St. and 67th St. The South Side discovered building over 63rd St. to be a bargain....there was little development west of Woodlawn Ave. except for the thoroughbred race track.....Washington Park. Property owners easily gave their consent, and the city agreed allowing the "L" to build a three track structure that included the spidery steel work over the raised embankment of the Illinois Central railroad. The entire extension from 40th St. to Jackson Park was built in under ten months. The east-west alignment alongside the Chicago Junction railroad would easily connect with two future extensions: to Kenwood and to the Stockyards.

In 1893, the exception to the "build through the blocks" was the politically connected Lake Street Elevated opened. The charter specified "build along and upon" and the elevated was constructed using the street as a right of way and no signatures were ever solicited. But neither the city nor the railroad was bold enough to build east of Market St. so proper signatures were gathered and the over the street elevated won a charter east as far as Wabash Ave. Along most of Lake St., the cross beams were wide enough to allow an express third track to be added. When the street is your right of way, there is not much that can intervene in planning your route. Had the Lake Street built any of its chartered branches, they would have been built on private land conforming to a "build through the blocks" clause.

In 1895, the third company on the scene put together the largest operation to date, a main line and three branches and all of it was built on private land. The Metropolitan West Side even brought their four track mainline to the edge of the Loop. The Met's four track main was constrained by Jackson and Congress east of Halsted; Van Buren and Harrison from Halsted to Sacramento Blvd.; and Adams and Polk from the boulevard west to the city limits.

Because of the extra number of blocks in the sections of land between Madison and 12th Sts. going west of State to the city limits in 1890, the blocks were more square than the typical rectangular city blocks with some lots having depths so deep that the "L" modified the customary "back of the lot right of way" and went through backyards with the garages on one side and the houses on the other. I would love to see photographs of those "L" structures. In 1950s The Congress Superhighway obliterated all traces. The extra wide blocks gave the Met room enough to put their shop building and powerhouse in between the two pairs of the four track main.

The four track main ended at Marshfield station, a half block west of Ashland AV and branches broke off in two directions: the Douglas Park directly south and the Logan Square directly north. The Garfield Park, now only a two track main continued straight to the west. But at Sacramento the two track main shifted its east-west alignment two blocks to the south for reasons I haven't found yet.

Both the Douglas Pk. and the Logan Square branches to the south and north were located in the typical back of the lot, along-side the alley, right of ways, along with 1/4 block land purchases when the alleys ran perpendicular. Several railroad crossings utilized masonry and concrete structures beneath the iron "L" structure and the branches crossed already raised steam railroad with majestic truss bridges. On the Douglas branch was an exception: where it went over the Burlington railroad on a tight acute angle crossing that simply used extra long reinforced bent beams in a design so strong it was left unchanged in the Pink line rehab a few years ago.

The north-south alignment of the Logan Square branch is almost all gone north of the overhead crossing of the Lake Street elevated near Paulina. I say almost because the 1894 era bridge that carried the "L" over the C&NW railroad tracks still stands today because the railroad has signals mounted on the structure. Not only is it the oldest surviving "L" truss bridge, it or the South Side Jackson Park east 63rd truss bridge was probably the longest ever built in the city. When the Logan Square reached the diagonal Milwaukee Ave., the "L" followed a course parallel to Milwaukee, alongside the alley, a routing distinguished by a speed reducing kink at North Ave. where the "L" adjusted to property lines. Just beyond this kink the now demolished Humbolt Park branch went west, again, alongside an alley but it never reached its franchised end point of the city limits.

North main at Sheridan.

North main at Halsted.

South main at 40th.

South main at 40th.

South main at 58th.

South main at 43rd or 61st.

South main at 63rd.

South main at 63rd.

Lake St. "K" town.

Met Logan Sq connector.

Met Douglas Pk Q bridge.

[chicagopcclcar]

So far we have examined four elevated operations. Three followed the "build though the blocks" as listed in their municipal charter. It was more economical to buy the strip of land at the rear of lots or purchase full lots then to bribe owners for a consent to use public streets or alley. But close to the downtown areas, it became more difficult, especially for two of the elevated companies.....the South Side and the Northwestern.

The first "L", the South Side broke ground next to the alley at 25th St., just east of State St. The right of way for the most part was strung out on the west side of the alley, except in between 14th and 12th Sts. where the line crossed to the east side of the alley. The South Side was stymied trying to purchase needed land north of 12th St. The property owners did however agree to sign consents for the "L" to build over Victoria, an alleyway with a name, known today as Holden Ct., so the city agreed to modify the charter.

Several plans for getting to the downtown over private property proved impossible and the Northwestern petitioned property owners for permission to use streets. With consents in hand, the elevated received new franchises allowing an "L" structure over N. Franklin and N. Wells, and a block east and west on present-day W. Hubbard St., continuing onto Fifth Ave. (Wells Ave.), but only allowing two tracks.... not the four tracks built to Wilson Ave. the north terminal which would continue to be a bottleneck down through history. This right-of-way included two 90 degree right angle curves on Hubbard, eased somewhat in the 1920s.

The two other elevated companies have little trouble get to the downtown. The politically connected Lake Street Elevated was constructed using the street as a right of way and no signatures were ever solicited and its tracks turned south Market St. south to W. Madison St. The Metropolitan West Side put together the largest operation to date, a main line and three branches and all of it was built on private land all the way to Fifth Ave. between W. Jackson and W. Van Buren Sts. The Met included a four track main from just west of Ashland Ave. to Fifth Ave downtown. All traces of the Met tracks east of Ashland are gone by the 1960s.

By 1895, three elevated had downtown terminals but that didn't put elevated passengers where they wanted to be so a plan developed creating a circuit of track around the downtown area. I did not use the term "loop" because there is a trivia question about that term. The Chicago "Loop".... comes before or after the "Loop" elevated?

The plan for distribution of elevated passengers became a four sided Loop and was completely constructed over streets, sometimes after bitter fights for consent from property owners. The Lake St. 'L' was built into the downtown first, receiving a franchised extension of the Lake St. charter; east from Market St. as far as Wabash. In a like manner, the Fifth Ave. side of the Loop was built as a franchised extension of the Northwestern Elevated. Two new franchises would complete the Loop elevated: the Union Elevated responsible for the Wabash Ave. side and the Union Consolidated Elevated responsible for the last side on Van Buren. That last Van Buren side was built using a ruse of chartering a mile long elevated from Halsted east to Wabash, but only building between Market and Wabash. It was easier to get consent signatures from industrial frontage owners in the west half of the mile than from the residential, commercial and retail owners in the east half. A simple majority, 51 percent approval from all the property footage along the entire mile as a whole was all that was needed. Perhaps to validate this ruse, the downtown "L" was numbered using the "proposed" Van Buren elevated as the origin. Number 1 would be the connection between the single track and the Met just east of Halsted St. Then whatever stations that were proposed; number 5 to the River crossing, number 6 to the second Met connection, number 7 for Franklin/Van Buren station, Tower 8 for Wells and Van Buren. When the numbering got around to Lake & Wells, Tower 18 was named. The Consolidated "L" west of Market St. was only going to be one track, located in the middle of Van Buren with single upright columns in the middle of the street. Of course this portion was a ruse and was never built.

The downtown elevateds used a lattice design called "open web" for stringers to let in more light at street level. While "urban legend" claims that opponents with the strongest objections would hold out for street uprights to prevent three and four tracks... curb line upright supports are included too, like along Van Buren and along Franklin St..... they were included in the franchise ordinances because they might have been the only option. Van Buren is only 66 ft wide, Franklin is 67 ft wide. Compared to the 80 ft. wide Wells and Lake Sts. and the 100 ft. wide Wabash, there may not have been room for "L" supports in the middle of the street. The location of in-the-street supports was usually defined as a certain distance outside of the streetcar tracks in the pavement.

When the Northwestern opened in May, 1900, several years behind schedule, this early stage of the Chicago "L" system still had much expansion ahead. Another trivia.... the was the first ever "L" station closed? We know the CTA was closed plenty!!!!

A SB charter rounds the eased curves over Hubbard St. at the Mart.

A SB runs on the connector at W. Chicago Ave. spanning the street track over Franklin St. and the private property trackage.

A test trip looking for problem areas brought the CTA Historic Cars 4271-4272 seen here as the cars rounded a toight 90 degree curve on the famed Loop "L".

Even Santa has been known to ride in the curves in the Loop.

The 2200 Charter comes off the South Side connection built over the alleyway in 1892.

A Brown line train is seen on the Van Buren St. leg of the Loop.

Three 3200 series trains are in this shot on the Wabash of the Loop.

Two trains use the 21st century engineering track easement that straighted the two curves at Harrison and Wabash on the South Main connector.

Does any rapid transit junction come close to have the complexity of Tower 18?

[TripleTransit1]

Does any rapid transit junction come close to have the complexity of Tower 18?

Tower 18: The best junction on the CTA.

[MTRSP1900-CTA3200]

I like the 40th curve. I remember going through it on the Snowflake Special and how the trains tilted on the curve. While I was sitting in one of the seats, all I could see was the sky out of the other window!

[BusHunter]

I like the 40th curve. I remember going through it on the Snowflake Special and how the trains tilted on the curve. While I was sitting in one of the seats, all I could see was the sky out of the other window!

I like the section of the englewood branch between the ex Wentworth station and Harvard station. There's really some good views in those 4 blocks and down by 63rd there's trains on three levels. The red, Green line and the freight. don't know what line that is.

[chicagopcclcar]

Tower 18: The best junction on the CTA.

Thanks.

Thanks to Kevin too!!

[MTRSP1900-CTA3200]

I like the section of the englewood branch between the ex Wentworth station and Harvard station. There's really some good views in those 4 blocks and down by 63rd there's trains on three levels. The red, Green line and the freight. don't know what line that is.

I've only been there once, but I think that's cool anyways.

Another curve I like is Harrison Curve. I remember the Orange Line Shuttle back when the curve was being straightened, and the Green Line trains only saying "Loop". I was downtown over the weekend, and I was telling my friend about the curve as we passed underneath it. He was quite surprised that it used to be two 90 degree turns.

[chicagopcclcar]

I like the 40th curve. I remember going through it on the Snowflake Special and how the trains tilted on the curve. While I was sitting in one of the seats, all I could see was the sky out of the other window!

The two "L" are on the Harrison curves, not the Green curves at 40th St. Note that the ties on the curves are milled from a single piece of wood. Most curve ties are two pieces to give the elevation that raises the outer rail. A SB train usually can get a 35 mph signal.

[MTRSP1900-CTA3200]

Tower 18: The best junction on the CTA.

No arguments there, although I did enjoy a private tour of Clark Tower/Junction once. It's amazing how many trains still go through Tower 18, even on the weekend.

[chicagopcclcar]

I like the section of the englewood branch between the ex Wentworth station and Harvard station. There's really some good views in those 4 blocks and down by 63rd there's trains on three levels. The red, Green line and the freight. don't know what line that is.

Norfolk Southern....in the old days, it was the Pennsylvania....then Penn-Central....Conrail.

[MTRSP1900-CTA3200]

The two "L" are on the Harrison curves, not the Green curves at 40th St...

Oh, I was recalling a memory, not referring to one of the pictures. Sorry for the confusion.

[BusHunter]

i wonder where on the system is the steepest bank angle. One would think on the fastest curve section of track if thinking scientifically on the basis of centrifugal force. Like maybe the bryn mawr curve on the blue line but personally it seems to me to be at Sheridan/Red line but the newer Harrison curve marries speed with those elevated curves so it could be there. There may also be the issue of deeper banks on a tighter turning radius which makes me think of the Halsted/North Avenue elevated curve.

[cta5658]

What about that Curve on the Dan Ryan portion on the red line between 69th and 63rd? even though it's not elevated, does that count?

[BusHunter]

What about that Curve on the Dan Ryan portion on the red line between 69th and 63rd? even though it's not elevated, does that count?

sure, I just didn't mention it. That would be comparable to the Bryn Mawr turn, you could also mention the turn at Bessie Coleman Drive outside O'Hare

[strictures]

I like the Orange Line turn as it goes from SW to S around 54th & Kilbourn. I've been there on trains when maybe 500 feet away are planes landing parallel that are lower than the train.

Very cool!

[Busjack]

What about that Curve on the Dan Ryan portion on the red line between 69th and 63rd? even though it's not elevated, does that count?

sure, I just didn't mention it. That would be comparable to the Bryn Mawr turn, you could also mention the turn at Bessie Coleman Drive outside O'Hare

Same at 47th. However, if one is using the expressway median, then I supposed someone would have to explain why the expressway jogs at those two locations.

[strictures]

Same at 47th. However, if one is using the expressway median, then I supposed someone would have to explain why the expressway jogs at those two locations.

I've assumed it jogs to go around the Rock Island's 47th St. shops.

North of there, it made sense to run it along the shared Rock Island; Lake Shore & Michigan Southern ROW, as it neatly split between IIT & Sox Park.

[chicagopcclcar]

BusHunter, on 13 May 2014 - 00:10, said:

i wonder where on the system is the steepest bank angle. ....... the fastest curve section of track if thinking scientifically on the basis of centrifugal force. Like mayb..... the bryn mawr curve on the blue line..... at Sheridan/Red line but the newer Harrison curve marries speed with those elevated curves .......f the Halsted/North Avenue elevated curve.

cta5658, on 13 May 2014 - 03:49, said:

What about that Curve on the Dan Ryan portion on the red line between 69th and 63rd? even though it's not elevated, does that count?

Curves and jogs started as a project showing how the way the elevated lines were buiit in the 1890s effect today's lines. They thought nothing about stringing 90 ft. curves around street corners. Of course the Loop has them on each corner. The South Side had three and a another pair when their Loop connector on Wabash was tied in. The Northwestern had two on Hubbard, two at North, and one at N. Water. The Lake put in one at Market. The Met West Side had two at Halsted and pair at the Loop Market connector. The South Side eased the two at 40th St. in 1907 while installing a three track. The Northwestern eased the Hubbard curves in the 1920s. The South main was reworked in 2003.

Some new discussions have surfaced. Look at some of the photos in this series and you will see curve construction .....new and old curves. New construction like in Hubbard, tracks 2 and 3 East at Sheridan, Harrison.

Wide curves seem to be some favorites but most have cab signal restrictions. Motormen were told in years past that the Dan Ryan's back to back curves between 63rd and 69th were the system's fastest. Had the "L" used the 70 mph, the superelevation curves are engineered for the job. Each track was laid out separately. Even the third rail was off-set. I don't know if the Ryan trackwork last year has changed it. Chicago "L" best curve for forty years!

I will said one thing for the Blue curve at Bryn Mawr....I think remember a 70 mph cab signal through stretch on a charter run. That was a good run. Of course the cab signal was to permit the "L" train to run without a penalty for exceeding 55 mph.

Protopype 5000 series on the Red line south on the reverse curve between 63rd and 69th Sts.

On the elevated structure the crown goes the Harrison curves on the Green/ Orange lines south of the Loop. I have heard the tracks can handle 55 mph. With the new interlocking machines setup is faster and 35 mph lineups go through much quicker.

A NB approaches Tower 12 on S. Wabash.

Speaking about the hardest curves, for years.....no!!! it wasn't on the "Loop." Motormen knew the tight curve was in the old Howard yards where the subways turned back. Of course that was removed when the new yard was built in. Trivia....how loops does the new Howard yard have?

[chicagopcclcar]

Same at 47th. However, if one is using the expressway median, then I supposed someone would have to explain why the expressway jogs at those two locations.

Strictures has expained the jog west of Wentworth. The Ryan west to State St., of south 67th, used land that was mostly vacant almost to 99th St. I remember a car dealership, numerous wholesale stores around 71st.