exist, but the line's right-of-way was destroyed by developments in the area. Early 21st century upgrades Automation and post-automation The Canarsie Line is one of only two New York City non-shuttle subway lines that hosts only a single service and does not share operating trackage with any other line or service; the other is the IRT Flushing Line, carrying the . Because of this, it was chosen as the location of the first fully automated line of the New York City Subway. The automation project was among the first in the world to use a radio frequency-based system. The plans for installation were laid out between 1999 and 2002. Communications-based train control (CBTC) was installed in pieces between 2003 and January 2006: the elevated section of the line south of Broadway Junction was completed first, followed by the underground section north of Broadway Junction. The project cost $340 million, with $78 million of it used to upgrade track interlockings on the line. In spring 2005, the current CBTC-enabled R143-class equipment was expected to run under full automation with a single operator (known as OPTO, or One Person Train Operation) acting as an attendant to monitor the train's operation and take over manual operation if necessary. However, technical mishaps including the test train rolling away by itself delayed the start of automatic train operation. The project caused numerous service disruptions on the L at night and on weekends. Frequently, service was shut down in separate sections of the line, usually from Eighth Avenue to Lorimer Street, Lorimer to Broadway Junction, or Broadway Junction to Rockaway Parkway. During this time, shuttle buses served suspended areas. This project also required the temporary closing of some stations, either in one direction or both directions, and for the line to be operated in two sections. In June 2005, the Canarsie Line ran full-length trains with a single operator on weekends. However, as this was a violation of union contracts – which stipulated that there must be one operator per of train – the MTA was ordered to resume two-person operation at all times. The system became operational . Automation was achieved with the R143s assigned exclusively to the L, but since the R160As were not CBTC-compatible until August 2010, some trains were manually operated alongside automatically driven trains. The L fully began automatic train operation in early 2012. The CBTC installation increased the train capacity