Y2K and WNRO: Implications for transportation

The Year 2000 (Y2K) problem stems from the fact that many computing systems use a two-digit format for the year instead of four digits. On January 1, 2000, computing systems may shut down or recognize 2000 as 1900, creating f urther problems with other dates. The week number rollover (WNRO) problem o f the Global Positioning System (GPS) will occur less than four-and-a-half months prior to the end of the century, on August 22, 1999, This is caused by the GPS timekeeping system, designed with a 1,024-week cycle beginning o n January 6, 1980, which will roll over from 1,023 to 0. The WNRO problem, not directly related to the Y2K problem, will affect GPS receivers that are not programmed to take this GPS week cycle into account. This article addr esses the implications of these two problems on transportation systems. It defines the Y2K and WNRO problems and discusses their impacts on various mo des of transportation and related systems. An action plan to deal with thes e problems is presented, The plan presents current efforts and proposes a c onceptual Y2K model that calls for a quick, effective, and partnership-base d effort. The model was applied to the public transit sector to illustrate how it might be implemented in practice, Useful information exchange tools and contingency planning (key elements of the action plan) are described. I mportant aspects related to legal and community issues are also briefly add ressed.