Sunday, February 14, 2016

Electrification



On February 12, 2016 Metra, the Chicago area commuter rail agency, retired the last set of "Highliner" electric powered multiple unit rail cars.  In honor of this auspicious occasion Player With Railroads revisits the why and how of Chicago's only electric commuter rail service.

On July 21, 1919 the City of Chicago passed the "Lake Front Ordinance" providing for electrification of the Illinois Central Railroad's suburban commuter service by 1927, freight service north of Roosevelt Rd by 1930 and south between Roosevelt Rd. and the city limits by 1935.  The eventual goal was the electrification of both the IC's and the Michigan Central Railroads' freight and intercity passenger service by the 1940's.

Steam era image of IC's Randolph Street commuter terminal.
The impetus for the ordinance was the smoke generated by thousands of steam locomotives operating in and out of the city as well as the numerous switch engines working in yards and industries scattered around the city.  It was felt that eliminating steam locomotives along the lakefront would go a long way to improve the air quality in the city.  No other railroad was made a party to the ordinance.

Track elevation.
The scope of the project was enormous.  It was what today we might call an "unfunded mandate" as the majority of the costs were borne by the railroad.  The tracks between 67th Street and the end of the line in Richton were elevated above street level.  In some cases the fill used to construct the embankments came from other improvement projects the IC had undertaken along their route south of the city.  At grade crossings with other railroads were eliminated for reasons of both safety and efficiency.  The grade level crossing to the South Chicago branch was eliminated and replaced by a tunnel that ran underneath the freight and passenger main line tracks and descended to the grade level tracks of the branch.  The largest and most complicated of these grade separation projects was at Grand Crossing, dubbed "the most dangerous railroad crossing in the world".

Grand Crossing grade seperation project.
The right of way was widened and additional tracks added with provisions for even more tracks to accommodate future growth.  A massive modern classification yard called "Markham" was built between Harvey and Homewood, IL, and designed to replace a number of smaller yards in Chicago.  Markham, located far outside Chicago's city limits, remained a bastion of steam until the advent of diesel electric locomotives.

Markham Yard (click on image for a larger view).
The electrical distribution was achieved by a 1500 volt DC system delivered to the overhead wires that powered the trains via 7 electrical substations owned by Commonwealth Edison.  High voltage Alternating Current was fed into the substations where it was "rectified" to the lower voltage Direct Current.  The substations also provided for the low voltage AC needs of the railroad such as lighting for stations and facilities, wayside signals and electrically operated switches at interlockings.  Steel "cantenary" structures were erected every 300 feet to support the overhead wire system that delivered power to the cars.  The cantenary supported not only the wires for DC and AC systems, but also the new signals and circuit control systems and communication lines.

Brookdale Substation
Right of way near 43rd Street.
Many of the IC's Victorian stations used during the steam powered commuter days were demolished and replaced with more utilitarian structures more suited to urban rapid transit use.  The new cars were designed for high level platforms rather than ground loading.  Rather than having passengers climb steps into the cars, the high level platforms allowed for direct entry into the cars cutting down loading times and speeding up schedules.

The 22nd Street Station was one of many stations that disappeared after electrification.
There was minimal electrification of the freight yards in the downtown Loop business district and yards on the near south side.  There were also some nascent diesel locomotives employed on the South Chicago branch for switching online industries.  The rapid development of the diesel locomotive would bring an end to any idea of further electrification beyond the suburban commuter service as they satisfied the requirements of the Ordinance.

Electric freight locomotive near 35th Street.
The new multiple unit cars (MU), so called because coupled units of multiple cars could be controlled by the motorman from a single control cab, were built by the Pullman Company in their south side plant along the IC mainline.  The cars were designed as motor car and trailer sets, with pairs coupled into longer trains of up to 8 cars.  The motor cars were equipped with a pantograph that drew electricity from the overhead wires when raised.  The pantograph could be lowered or raised by the engineer in the cab, or with a special insulated pole in the event failure of the automatic system.  The cars were equipped with special couplers that carried the electrical connections for control as well as the air connections for brakes.  The cars could be coupled and uncoupled by the engineer in the control cab as well as manually outside the train.  Despite not being powered, the coaches had a duplicate control cab making the cars bi-directional without having to turn them.  The IC had briefly considered the idea of using electrically powered locomotives with unpowered coaches, but eventually chose the MU equipment.

Pullman Multiple Unit motor car and trailer.
What the new Pullman cars did not have was air conditioning and bathrooms.  When they were replaced by the new double-decked "Highliner" cars beginning in 1971 air conditioning was included, but not bathrooms.  Commuters would have to wait for the delivery of the latest version of the Highliners to have someplace to take care of business.

Electrification Day celebration.
August 27, 1926 was a day of celebration as electric service was initiated.  The massive civil engineering project that was undertaken brought fast, efficient and clean mass transportation to Chicago.  The retirement of the second series of equipment by Metra, successor to the Illinois Central, marks the ongoing improvement of a system that has served commuters from the the south side and southern suburbs for 80 years.  Much of the physical system remains in place and will continue to be upgraded as public funds permit.  This is a credit to the quality of design and construction built into the original project.