Chicago Transit System Capacity Enhancements, USA

The Chicago Metro has a long-standing history as part of the US city's lifestyle, and is now as much a landmark as a transit system. It transports more than 1.5 million passengers every day across a network that spans 355km (222 miles) serving businesses and local communities alike.

The metro dates back to 1892, and its raised tracks have seen the system become known as the ‘L’ – for elevated – following in the footsteps of the complex New York elevated railway. Chicago’s transit system is the second largest in the USA, but capacity is restricted by its age and is a major issue for the operator, the Chicago Transit Authority (CTA). It is investing to improve track speeds and capacity on three of major routes, together with rebranding the route to the University and adding a city centre loop.

THE PROJECT

Modern railway operating practices and high-spec equipment have placed heavy demands on the infrastructure of the Chicago Metro. The network has 151 stations, with 18km (11.25 miles) of route underground, 62km (38.75 miles) on elevation – mostly in the city centre, which itself has 89 stations. Both airports are served by the metro.

A layout of eight lines is operated alongside an extensive network of bus routes (also part of Chicago Transit Authority's remit) and the extensive Metra suburban rail services. Route improvements will allow for capacity increases on three of the major routes – Blue, Red and Brown. In total over US$1.25bn is being invested in infrastructure.

INFRASTRUCTURE

Red Line opened in September 1969 and accounts for more than 63 million passenger trips per year. The infrastructure is now reaching its limit, and CTA is investing US$282.6m in refurbishment.

The aim of the project is to bring more reliable and efficient operation involving power, signalling and communication upgrades on 14km (9 miles) between Cermak-Chinatown and 95^th Street. Major station renovation is also taking place at several locations.

The power upgrade is required to meet the needs of a modern Chicago. The route was designed for a 5–7 minute train frequency with six-car trains, but in 2006 eight-car trains run at 3–5-minute intervals in peak times. Modern cars draw more power, making the upgrading of air-conditioning units a further drain. Two sub-stations are being upgraded and the third-rail used for current collection is to be replaced. Seven stations are being refurbished with new floors, rebuilt canopies, lighting and improved signage.

Brown Line is one of Chicago's main transport arteries, serving the residents and businesses in the north west of the city. It is one of the earliest to be built, and in 2006 has been one of the CTA's busiest routes with 66,000 passengers each weekday between its 19 stations. There has been massive passenger growth – 83% since 1979 and 27% since 1998.

Brown Line is one of only two routes of the Chicago Metro that cannot accept eight-car trains, and US$530m is being invested in the line to increase capacity and improve accessibility.

Longer platforms are being built to accommodate eight-car trains instead of six, and stations are being equipped with modern facilities, including wider stairways, extra entrances and exits, and more turnstiles to improve passenger flow at peak periods.

The third line to be tackled by the CTA is the Blue Line, which has deteriorated to the point that half its length is subject to speed restrictions of 24km/h (15mph). Full line speed is 88km/h (55mph). US$482m is being invested in this line, which runs on a 100-year-old elevated route.

Specifically, six elevated stations will be rebuilt, along with two ground level stations. New foundations are being installed on 80% of the elevated route and rails are being re-laid throughout, together with more train storage and a washing plant, two new substations, signalling and improved communications.

ROLLING STOCK

CTA operates a fleet of 1,200 metro cars. They are generally formed into eight-car sets, although the Purple and Brown Lines can only accommodate six-car trains.

The most recent to enter service are the 3200 Series cars for the opening of the Orange Line and replacement of older cars on the Brown and Yellow Lines.

A new order was placed with Bombardier in May 2006 for 406 new cars, with an option for a further 300. The first delivery will be 206 cars from 2010, worth US$577m. They will be used to replace older 2200 Series Budd Cars dating from 1969–70 and 2400 Series Boeing-Vertol cars procured in 1976–78.

The new cars will feature aisle-facing seats to allow more passengers to board, alongside improved security. The use of AC traction motors is a change from the traditional DC equipment currently in use, but the new trains will operate from the same 750V DC third rail supply.

SIGNALLING AND COMMUNICATIONS

Red and Blue Lines are both receiving major signalling and communications upgrades. This comprises a new two-way in-cab signalling system, together with on-track equipment and new control rooms. Fibre optic communication cables are being laid to connect all stations with the CTA centre.

THE FUTURE

The issue of capacity is being addressed by the CTA on its three major routes – Red, Brown and Blue – which together with the fleet of new cars from Bombardier will bring great changes in the system's ability to cope with growing passenger numbers.

Extensions planned include taking Orange Line (opened 1993) from Midway Airport to Ford City, and Red Line south to 130^th Street. There is also a proposal for a new loop line around the outskirts of the city.