The Bay Area Rapid Transit District (BART) opened to serve the San Francisco Area in early 1972. After World War n, busses were replacing the extensive, but deteriorating light rail systems in the area. The need for a modem rail transit system was conceived at this time. BART began as a commuter system providing a way to work for those living in the communities East of the San Francisco Bay. Since that time, BART has grown into an integral part of the Bay Area. Ridership demands have expanded from rush-hour commuting to include heavy non-commute usage. The original system began with 71 route miles, 148 track miles and 271 turnouts. The system has now expanded to 97 route miles, 210 track miles with 452 turnouts. Soon with the extension to the Airport in San Francisco, BART will gain and additional 15 track miles and 47 turnouts.Turnouts represent a major maintenance concern for BART's track maintenance forces. Inspection and maintenance of turnouts and switches are critical to safe and unrestricted operations of trains. The components that make up a switch have little tolerance for wear before reaching a point where they fail or create a derailment hazard. Replacement of these components is expensive, time consuming and resource intensive.Limited track occupancy time is a major challenge in performing maintenance. Track time availability for maintenance is limited at BART; some locations as little as two hours a night. The longest windows available for switch maintenance are on Sunday mornings. That one day a week has only six hours available. Another challenge is added by the design of BART's automatic train control system. It does not allow maintenance of switches during revenue operations. Excessive delays to train operations resu which is not an option on our system. Switches are not the only devices requiring maintenance and competition for the limited track time is stiff. Capitol improvement programs, contractor support, structures maintenance, electrical distribution systems, automated train control and other track items also require track occupancy to be completed.Track occupancy is only guaranteed at BART with adequate advance planning. To forecast when switch maintenance is required, a defined maintenance criteria is needed. The original standard was modeled from 213.135(h) of the Federal Railroad Administration's Track Safety Standards. This, in part, states that "Unusually chipped or worn switch points must be repaired or replaced". With the limitations of the BART system, this standard became unacceptable for maintenance. Track Inspectors and maintenance planners needed definite limits for deciding when switch points and stock rails require replacement.Quantitative methods and standards used for maintaining switch point and stock rails were developed. These processes, integrated into the track inspection and maintenance program, provide the tools necessary to guide inspectors and maintenance planners. This has provided BART with a more economical maintenance program and safer operations; in challenging maintenance environment. Definite standards help maintain the fine balance between safety, economy and efficiency, without compromising safety; our customers will accept nothing less.
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