FHWA's MUTCD guidance (Part 4E) on pedestrian signal timing is problematic and should be revised. When FHWA published the 2009 guidance and moved to using 3.5 feet per second, you relied on two studies to support that change: 1) Transit Cooperative Research Program (TCRP) Report 112, Improving Pedestrian Safety at Unsignalized Crossings and 2) Institute of Transportation Engineers, The Continuing Evolution of Pedestrian Walking Speed Assumptions. Both articles show that although many people do walk or wheel at 3.5 feet per second or faster, people with disabilities walk significantly more slowly. The TCRP report, in particular, showed that mean walking speeds for people with various types of disabilities are much slower than 3.5 feet per second. For example, mean walking speed for a person with a walker was 2.07 feet per second (and remember this is just the mean). Moreover, while the MUTCD includes a provision recommending use of a lower walking speed where people walk more slowly, the guidance is confined to locations where disabled pedestrians "routinely use a crosswalk." This is absurd. Pedestrians who are disabled have the right to use any crosswalk, regardless of how many other people "routinely" use it. Similar issues exist with respect to the minimum "walk" time of 4-7 seconds recommended by FHWA. Not everyone is able of leaving the curb during that short a period of time, especially if drivers are allowed to turn right on red at the intersection, since many drivers fail to stop and yield before turning. FHWA also should revisit its guidance on minimum "walk" times, or at least mandate that, where engineers provide only this minimum walk time, right on red must be prohibited.
The solution to this problem is not to just keep lowering the mean walking speed -- that will never make street crossings accessible to everyone -- but to address the issue with technology that can reliably detect when any pedestrian is still in the crosswalk and extend the signal timing until they finish the crossing. This approach also would be far more consistent with historic court decisions holding that people who begin crossing with a "walk" or green signal have the right to complete the crossing. See, for example, Quaker City Cab Co. v. Fixter, 4 F.2d 327, 328 (3d Cir. 1925); Griffith v Slaybaugh, 29 F.2d 437 (App. D.C. 1928); Riddel v. Lyon, 213 P. 487 (Wash. 1923); see also Peck v. United States, 195 F.2d 686, 688 (4th Cir. 1952) ("The pedestrian's right of way extends from one side of the street to the other. It does not begin at any particular point in the intersection, nor does it end at any particular point. It begins on one side of the street and extends until the pedestrian has negotiated the crossing.")