According to the late George Krambles although the concept a multi modal transportation corridor is an old one Chicago was the first city to apply the concept of integrating use of right-of-way for both an automobile expressway and heavy rail rapid transit line. The idea of using the median of expressway for transit was born of necessity. Congress Expressway plans called for 550 feet of right of way west from the central business district to the city's western boundaries and beyond. In the path of the preferred alternative was the track and structures of the former Metropolitan West Side Elevated Railway by then part of the Douglas Garfield CTA Lines. The railway’s right-of-away was as wide as 75 ft. in some places and in the end this transit right-of-way was “the most important single land acquisition needed for the highway” in George’s estimate. For about 6 miles the median was used to replace the old Garfield elevated route while the last 3 miles the transit line ran along the south edge of the highway essentially sharing space but not tracks with the Soo Line Railroad. One result of the transit being immediately adjacent to the expressway in this area was the left hand expressway access and egress at Harlem and Austin Avenues. The new Congress Transit Line opened in stages between 1958 and 1960.
CTA studies showed that the transit system installation and construction costs were only about 20% of the cost of the expressway. More over they calculated that the number of transit passengers in the peak period exceeded those of the highway with substantially more capacity available than the highway. Ten years after it opened the Congress line, with relatively modest density transit routes serving it, carried over 100,000 riders per weekday. George Krambles noted that ” an incidental benefit was the elimination of about 6 1/2 miles of obsolete steel L structure with its costly maintenance and esthetic objections”.
The successful effort to preserve the Garfield CTA Line by using the median was not the same as that experienced by the Chicago Aurora & Elgin interurban. This well built interurban had 80 pound rail, with rock ballast and concrete structures. More importantly it was the only interurban in the region that used the third rail for electrical pickup and in 1907 began to run on the Garfield line into Chicago. The line had seven stops between downtown and Wolf Road, servicing both Aurora and Elgin, although its major boarding occurred in Wheaton. As the Congress was being planned in 1953, the Chicago Aurora & Elgin dropped downtown service leaving their riders without the desirable one seat ride to the loop, necessitating a transfer to the Garfield line at Forest Park. In 1957 despite only a few miles of the Congress Expressway carrying commuters the Chicago Aurora & Elgin had run out of passengers and money. On June 3 at midday the commuter service was permanently terminated leaving hundreds of returning commuters stranded at Forest Park and causing a near riot when they realized that that was as close to home as they were going to get. In a rare note of transit optimism, that same summer the Chicago Aurora & Elgin bridge over the Des Plaines River was moved (rather than destroyed) slightly north to accommodate the expressway and remain available for the resumption of service. The re located bridge was never used to carry scheduled passenger traffic over the river.
Although the use of the median of the Congress for transit was in response to the need to replace an existing line the idea was quickly perceived as a means to expand transit as the other expressways were planned and built. When the decision was made to incorporate transit into the medians of the other expressways much of the planning and right-of-way had been purchased and the city decided that little or no additional right of way should be acquired beyond what was on hand. Since much of the right-of-way for the Congress, Northwest and South had already been purchased that would suggest it was a problem. But in many cases that did not pose a major problem since the logical width of the right-of-away (from street to street on a straight north-south east-west orientation) left some unused property. Also the expressway planning generally called for a 50 ft. buffer between opposing traffic streams. This was enough to generally accommodate the minimum 43 feet needed for a double track rapid transit line and the station platforms.
On portions of the Northwest Expressway the need to squeeze more into the right-of-way was a bit more complicated than some of the other locations. Agreement had already been reached on the use of reversible express lanes from Ohio Street to the Northwest / Edens junction. Some of the original proposals had the Logan Square CTA line extend east to the Northwest Expressway at Logan Boulevard. This would have resulted in a conflict with the ramps that provided access and egress for the express and regular lanes at Diversey Avenue. The final plan had the transit line emerge from subway onto the median near Kedzie Avenue between the express and the out-bound regular lanes.
West of this area the Northwest was and is noted for the extensive landscaping on the perimeter of the expressway. This is partly the result of needing to squeeze as much into the right-of-way as possible. The county chose in many areas to leave a steep slope rather than build retaining walls. In order to hold the slope and because it was too steep to be mowed the county's landscape architects led by Morrie Cherner designed and installed plantings. The result turned out to be practical as well as pleasing to the eye.
On the South Route the state said they would not pay for the extra right-of-way to accommodate the CTA in the median. For much of the South Route and especially on the state section this was not a major problem because it was straight North South and the right-of-away went from block to block leaving enough to accommodate the transit line. But at the bridges, to accommodate stations, an additional 50 feet was needed. The state paid the extra local match and Marshall Suloway (at the time the Expressway Engineer for the state) negotiated a 1.2 million dollar reimbursement from the city. But the city never paid and when Marshall became the Commissioner of Public Works one of first call's he got was from Roger Nusbaum, now Chief Engineer for the state, reminding him of the debt. He doesn't think it was ever paid meaning that despite the agreement the state and the county probably paid, not the city or CTA for the extra transit right-of-way. Mike Hartigan noted that as the planning for the South Route intensified it became clear a decision on the federal participation in the extra cost of the right-of-way for the CTA needed to be resolved. He said a big meeting with lots of staff and much show and tell was held for the benefit of Joe Barnett from BPR. During the course of the meeting Joe reiterated the Bureau's position that they could not participate in the cost of the extra right-of-way. After the meeting Barnett went to lunch with Bartelsmeyer, Mortimer and Dement. Later that day it was announced that BPR would agree to pay 78% but not 90% of the cost of the additional right-of-way.
When the Northwest and Dan Ryan expressways opened they had the right-of-way but not the transit extensions. Several things happened in the next several years to make the extensions a reality. In 1964 Congress passed, inspired by President Kennedy, the Urban Mass Transportation Act. For the first time federal funding was available for the purchase of transit equipment and the construction of transit facilities. Two years later Mayor Daley as part of a major infrastructure improvement program proposed a transit bond issue. The transit funds were approved in a citywide referendum and the city began to immediately plan for the transit lines. Subsequently Chicago received a 50% grant from the Urban Mass Transportation Administration to build and equip the two extensions. Chicago's clout with the Johnson administration was apparent from the large percentage of the available UMTA money that went for the two Chicago projects. By the fall of 1969 the Kennedy Expressway (now named for the assassinated president) transit line was open to Jefferson Park, while the Dan Ryan opened as far south as 95th Street four months later in February of 1970.
Planning and construction of the Southwest Expressway included provisions for transit southwest of Damen Avenue. Although the Southwest does not have a transit line in the median it was one of the first to be considered for transit use in earlier plans. The construction of the two extensions in 1969 and 1970 did not end the planning and construction of transit in the expressway medians. After several years of study and debate the extension of the Kennedy CTA Service (The Chicago and Northwestern Railroad still a private enterprise feared the effect it would have on somewhat adjacent service) to O'Hare Airport became a reality. Several studies were done to look at the feasibility of running transit further south than 95th Street using the available right-of-way on the Calumet Expressway. This extension has not happened. In the 1980’s studies were begun to look at transit service to the Southwest side of Chicago and Midway Airport. The Orange Line was the result, although it does not use the Stevenson median, it does run parallel to the expressway as far as 35th Street then south mainly on old railroad property. During the planning for the Crosstown Expressway a variety of alternatives were proposed for both the roadway and the transit line. Although the roadway appears to be dead after many resurrections in various forms over the years, the transit line is alive in the current regional plan in the form of the Mid-City Transit-way.