As the name suggests, transit-oriented development (TOD) is anchored by some form of public transportation, typically a train line. It has been widely accepted as an important planning paradigm to create attractive, livable and sustainable urban environments. The purpose of TOD is to concentrate housing and commercial development close to existing (or occasionally, extended) transit infrastructure, thereby providing an alternative to automobile trips. Most TOD development radiates roughly a half mile – or less than 10 minutes walking distance – from its anchoring rail station.
In the Chicago region, potential sites for TOD are plentiful. The CTA has 142 stations on its seven rapid transit lines along 100 miles of rail, while Metra's suburban service comprises 239 existing stations, with plans for 33 more potential stations through Metra's four current New Starts projects (UP-W Upgrade, UP-NW Extension and Upgrade, new SouthEast Service Line, and new STAR Line), on 11 existing commuter rail lines along 489.2 route miles. TODs can also be anchored by bus stations or terminals, or near major stops along Bus Rapid Transit (BRT) systems.
The remainder of this section describes the general features of TOD and provides local examples of its applications. A systematic assessment of existing and potential TODs in the region is planned to be added to this section at a later date.