Appendix D: Right Turn Slip Lane Design GuidelinesAnchor: #i1002995
Section 1: Introduction
Right-turn slip lanes are advantageous to motorists as they reduce delays by separating right-turning traffic from through lanes and allow higher-speed right turns. The right-turn slip lane channelizing island can also provide a refuge area for crossing pedestrians, reducing their exposure by allowing them to cross the roadway in two stages. Providing safe mobility for pedestrians and cyclists while reducing delays for motorists are potentially conflicting objectives. Accordingly, right-turn slip lane designs should create a balance between the safety and mobility of all roadway users.
This Appendix provides guidance on the design of right-turn slip lanes, including lane and raised island geometric layouts, pavement marking guidelines, pedestrian and bikeway guidelines, and accommodations for pedestrians with disabilities. Guidance is provided for urban, suburban, and rural roadway environments. Common issues at existing right-turn slip lanes have also been identified and treatment options for retrofitting are provided.