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 ainly 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.
Jacob Tsao and A Pratama. "Efficient Space Dedication to Bus Rapid Transit or Light Rail Systems" Journal of Public Transportation (2013): 79-94. doi:10.5038/2375-0901.16.3.5