Efficient Space Dedication to Bus Rapid Transit and Light Rail Systems

Dedicating two lanes and passenger platforms to transit typically requires taking the same space away from general use. This may affect public support. This paper proposes efficient geometric configurations for a two-dedicated-lane BRT or light rail system that requires a minimum amount of right-of-way along a busy commute arterial. In many current busy commute corridors, a significant part of the street median is underused or unused for traffic purposes. The efficiency is achieved mainly by using the street median between a left-turn lane and its counterpart located at the intersection on the other end of the same street section and slanting part of the two dedicated lanes with respect to the longitudinal direction of the street. Instead of the three-lane or even four-lane conversion required of the prevailing configurations, the proposed configurations require conversion of only two lanes from general use, even for a section equipped with passenger platforms. Introduction Public transportation is perhaps one of the few sustainable transportation solutions for urban or suburban areas. Most, if not all, cities have public transportation systems. However, relatively few provide rapid transit systems. An urban rail or light rail system is the classical and conventional transit system used in most developed countries as well as in some cities of emerging economies (New Delhi, Beijing, Shanghai, etc.) while bus rapid transit (BRT) is a relatively new mass-transit concept that has been adopted by both developed countries and emerging economies Journal of Public Transportation, Vol. 16, No. 3, 2013 80 (Levinson et al. 2002; Jarzab et al. 2002; Diaz et al. 2004; Miller et al. 2006; Kittelson & Associates et al. 2007). The operational concepts and geometric configurations proposed in this paper are applicable and beneficial for both BRT and light rail. For ease of discussion, we address BRT explicitly in the rest of the paper and provide geometric sketches and justification only for BRT operations. To minimize travel time and its variability for BRT, traffic lanes together with spaces required for the concomitant passenger activities along a street median can be dedicated to form a dedicated transitway (Li et al. 2009). In addition, transit signal priority (TSP) and other technologies can be adopted to improve system performance. However, the current vehicular traffic of many cities is dominated by automobiles. Such cities include perhaps most U.S. cities, with few exceptions (New York City and Chicago), and many cities in other developed nations or emerging economies. Dedicating two lanes in the street median and the additional spaces needed for bus stops often requires taking the same space away from use by automobiles. In prevailing geometric designs for dedicated BRT systems, passenger activities at a bus stop are accommodated with either two physically-separate passenger platforms (one for each direction) or one dual-use platform. In either case, the width of the required space is approximately the width of two traffic lanes. This kind of lane conversion could lead to heavy congestion during peak commute hours unless parallel streets or even corridors have sufficient capacity to accommodate the redirected traffic. In addition, the possible low bus-traffic volume on such a dedicated transitway before the demand for bus services can be gradually built up could lead to the impression of space underutilization; such impression is sometimes referred to as the “empty-lane syndrome.” Such possible congestion and syndrome could lead to strong motorist resentment against implementation of BRT on a dedicated transitway. An alternative to such lane conversion is right-ofway purchase, but the cost may be prohibitively high and land-owner resentment may be strong. These may be primary reasons why few such dedicated systems have been implemented in North America. Phase I of the Viva BRT system, designed for the York region of Ontario, Canada, was opened in 2005, and its Phase II, featuring several dedicated transitways accommodated on the street median called “rapidways,” is being implemented with a full funding commitment of $1.4 billion Canadian by the Province of Ontario (York Region Rapid Transit Corporation 2012). Much of the required additional right-of-way was purchased. Although the Orange Line of LA Metro has recently been implemented almost entirely on exclusive lanes (except for several blocks