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27 automated methods of gap and yield detection. It should be order to make most efficient use of project resources and to noted that, although considered in the internal survey, auto- allow for a direct comparison using the same participants. mated gap and yield detection capabilities of the type that have undergone preliminary field evaluation in the NIH/NEI proj- Channelized turn lane: The team recommended instal- ect (NIH 2010) are beyond the scope of what are consid- lation of sound strips and lane delineators to provide addi- ered off-the-shelf treatments available for evaluation by tional auditory information to blind pedestrians about NCHRP Project 3-78A. Such treatments, while promising, traffic patterns in the CTL and to distinguish that traffic are too experimental at this point to be considered as avail- from adjacent through movements. The team further able treatment options for state DOTs. The concept of a sur- recommended testing the sound strip and lane delineator face sound-strip treatment showed potential in prior research treatment in isolation and supplemented with a pedestrian- (Inman et al. 2005) and was considered for further study at actuated flashing beacon. The latter was intended to test the single-lane roundabouts and CTL crosswalks. effect of enhancing pedestrian visibility to the driver and the Signalization treatment options generally showed mod- effect of the treatment on increased yielding behavior. This erate to high potential for reducing delay and risk for blind proposed approach provides a measurable effect of three pedestrians. As might have been expected, vehicle delay was possible CTL treatments: the effect of sound strips, the effect judged to be negatively affected for signalized treatments. of sound strips in combination with a pedestrian-actuated Of special interest was the PHB, an innovative signalization flashing beacon, and the flashing beacon alone (derived strategy that reduces vehicle delay through unconventional from the net difference between the two installations). The phasing while still providing a red vehicle display and associ- use of lane delineators was a fixed addition, assuming that ated walk phase for pedestrians. they would be necessary to ensure proper functionality of Initial estimates of potential treatment effectiveness were also the sound strips. obtained for crosswalk geometry modifications and showed Single-lane roundabout: The team recommended the same moderate potential in the ability of blind pedestrians to detect treatments used for the CTL, but for obvious reasons with- gaps and yields. Lastly, grade-separation treatments were rated out the lane delineators. Proposed treatments were sound as having the highest potential impact on behavioral param- strips in isolation and sound strips supplemented with a eters and performance measures. However, the applicability pedestrian-actuated flashing beacon. The same assumptions of modified crosswalk geometry and grade separations as treat- and control factors applied since two different approaches ment options to be considered under this research effort was of the roundabout were recommended with similar geome- low due to the high costs and permanent nature associated tries and traffic volumes. with the treatments. Two-lane roundabout: The team recommended installing two different treatments at two approaches of the same two- lane roundabout: A raised crosswalk (RCW) intended to Treatments Recommended for Installation slow traffic and increase yielding, and a PHB intended to The results of the team treatment survey were used to stop traffic at a red signal display and to provide additional develop recommended treatments or combinations of treat- audible information to the blind pedestrian. The team con- ments for installation at the test locations under consideration cluded that installing these two significant treatments was of the project scope and budget. Each installation required reasonable given the perceived challenges at two-lane cross- cooperation from a municipality, was associated with instal- ings and the draft PROWAG language. lation cost, and required substantial team resources for data- collection planning, execution, and analysis. Treatment rec- Additional details on the specific treatment installations ommendations were chosen based on the perceived level of are provided after the discussion of site selection and along effectiveness in producing a measurable impact on the occur- with the overview of the test sites. rence of yielding events or utilized gaps. Recommendations also considered the level of cost associated with installing Site Selection the treatment and the expected benefit to travelers. Due to the relatively low number of available sites willing to install treat- The research team evaluated a list of potential study sites and ments, as well as budget constraints that limited the number selected those that were deemed suitable for further field inves- of sites for which data could be collected, combinations of tigation of the proposed treatments. Criteria for site selection treatments were considered a plus. Based on these factors, the included: team recommended installing two treatment installations. The team recommended testing these treatment combina- Feasibility of implementing one or more of the desired treat- tions concurrently at two CTLs of the same intersection in ments at a given site within project schedule and budget;