Nathanael T. Wales
|September 23, 2002|
I have reviewed the Board's Draft Guidelines on Public Rights of Way (Sections 1100 through 1111). Having reviewed them, I am e-mailing the following comments to you in advance of my attendance at the Board's public meeting on October 8 in Portland, Oregon. I will also bring a written copy of these comments to the meeting.
I am blind and am a member of the National Federation of the Blind. Professionally, I graduated from the University of California at Davis in 2001 with a Bachelor of Science degree in civil and environmental engineering, and I have worked full time for a little more than the past year as a water resources engineer for the State of California. I am commenting on these draft guidelines as a blind person living in and traveling independently throughout the Sacramento, California, area; as an engineer who has taken civil engineering planning and design courses at the university level and who has worked in the field specifically doing planning work on civil engineering projects in collaboration with other governmental agencies; and as one who has professionally reviewed thousands of pages of public comments on engineering projects and their guiding policies (and who is therefore sensitive to the volume of comments of which these are a part).
Overall, I believe that the draft guidelines will greatly improve access for the disabled to public rights of way. In general, I believe that regulating new and altered public rights of way to these standards will improve not only access to the disabled but also overall pedestrian safety and will heighten the regard that the general public holds towards walking as an alternative to driving. I do, however, wish to comment on and express my concern about two general areas of the draft guidelines that are directed at improving access for blind pedestrians: the use and design of detectable warnings on curb ramps (1104.3.2, 1105.4.2, and 1108) and the use and design of accessible pedestrian signals (1106). In short, I believe that the draft guidelines are unnecessarily broad and sweeping in scope and far too restrictive and prescriptive in design. These portions of the draft guidelines are precisely the sort of regulations that frustrate planners and engineers and may ultimately cause local governments to decide not to make safety improvements at intersections--even at the most dangerous intersections--because of the substantial expense of following these prescriptive and inflexible guidelines.
First, I believe that the scope of requiring detectable warnings on curb ramps and pedestrian refuge islands (1104.3.2 and 1105.4.2, respectively) is unnecessarily broad. I appreciate the Board's invitation for public comment on this specific matter, and I am pleased to provide mine. It is my experience as a blind pedestrian using a white cane that curb ramps are very accurately detectable because I am able to detect with my cane and underfoot the change in slope on the ramp in combination with other clues indicating that I am approaching the intersection (such as cross traffic, idling cars, the corner of a building on the block, and the presence of a perpendicular sidewalk). Only the most shallow curb ramps and blended curbs (generally a bad idea in almost every case because of dangerous turning traffic and more difficult drainage) are more difficult to detect precisely. Generally, I and most other blind pedestrians use other environmental clues (such as those I mentioned above) to accurately locate the intersection and find the location of any shallow curb ramp or blended curb safely. It is therefore my opinion that detectable warnings should only be used on the most shallow curb ramps (those with a slope of 1:15 or shallower) and on blended curbs, if at all. I believe that these principles also apply to the use of detectable warnings on pedestrian refuge islands, and I note in particular that pedestrian rights of way cut through a refuge island without any curb ramps are easily detectable because of the obvious presence of the edges of the cut made through the elevated and often landscaped island.
My experience traveling throughout Sacramento is the basis of my opinion. The city, as part of the settlement of a lawsuit, is rebuilding thousands of very poorly designed and constructed curb ramps. As part of the plan the city council adopted from the public works department, detectable warnings are only being used on curb ramps with a slope of 1:15 or shallower. Many new curb ramps have been built or re-built within a few blocks of the Capitol and my state office building. None of these newly constructed curb ramps have detectable warnings, yet other blind pedestrians and I have accurately and safely detected them because of their moderate slope (between 1:15 and 1:12, by the prescription of the plan that the city adopted), their distinct edges parallel to the direction of travel, and their obvious proximity to cross traffic.
Further, I believe that the design prescribed for detectable warnings (1108) is overzealous, inflexible, and impractical. The draft guidelines require 2 feet (ft.) of detectable warning tiles wherever they are used. 2 ft. is far more length along the pedestrian right of way than is necessary; a much shorter length such as 6 inches is in my experience fully adequate and more economical. The requirement that detectable warnings must be and only must be plastic tiles of truncated domes fails, in my opinion, to allow the use of other detectable surfaces that may easily and provably provide equivalent facilitation (such as scoring of the concrete, use of additional aggregate in the concrete mix used, and a smoothed cobblestone design). Finally, plastic tiles of truncated domes may be impractical in many situations because they are difficult to clean with standard street sweeping equipment (a particular problem in the often leaf-blown streets of Sacramento) and because they pose a tripping hazard to pedestrians such as women wearing high heels (that is, they may be a personal injury lawsuit waiting to happen and a trial lawyer's dream).
Secondly, I believe that the draft guidelines regarding the use of accessible pedestrian signals (APS's) (1106.2) are equally as broad and overreaching. Because I and other blind pedestrians, whether we use a white cane or a guide dog, determine when we have the walk interval and it is safe to cross based on a number of factors including not only traffic patterns in the intersection but also whether other pedestrians and bicyclists are crossing in our desired direction, APS's are generally unnecessary. These techniques work well and very safely in the vast majority of intersections, including four way intersections and intersections between one-way streets. It is only at a relatively small number of intersections in very specific cases that I and other blind pedestrians have found that APS's are needed. Such specific cases include intersections between a street with a high traffic volume and a street with a very low traffic volume (and at such intersections an APS is only needed for crossing the high volume street), T-intersections (and at such intersections an APS is only needed for crossing the through street), intersections with one or more left and right turn slip lanes (and at such intersections an APS is only needed to cross the one or more turn slip lanes), and roundabouts (cases that may prove less favorable for traffic flow because of the need for pedestrian activated signals for all pedestrians).
Further, the requirement that an APS have both an audible indication of the walk interval (1106.2) and a locator tone (1106.3.2) is unnecessary in all cases for me and other blind pedestrians. The vibrotactile indication of the walk interval is completely sufficient. In fact, an audible indication will not only add to noise pollution but also mask audible clues in the environment (such as other traffic) that we use and will further potentially disorient those of us mistakenly using the audible indication from the APS to find the way across the intersection. In addition, locator tones on APS push buttons are entirely unnecessary, especially in consideration of the draft guidelines' specific requirements for the location of pedestrian crossing push buttons. Rather, locator tones will add greatly to noise pollution at the intersection during every second of every minute of every hour of every day of every week of every month of every future year, will be difficult to distinguish on channelizing islands at intersections with turn slip lanes (which may require up to three locator tones within a few square feet) and may further cause blind pedestrians to become disoriented on such islands, and may finally mislead blind pedestrians crossing an intersection away from their destination corner.
In conclusion, on these two broad matters I believe that the current draft guidelines' broad scope and extraordinarily restrictive and prescriptive approach to intersection safety and public rights of way accessibility will frustrate engineers looking for innovative and tailored solutions to the specific design situations with which they work. These draft guidelines will provide engineers with little flexibility in implementing more effective detectable warnings less prone to such problems as leaf cover in Sacramento or less likely to be the cause of a personal injury liability for their local government. The overzealous implementation of APS's may result in noise pollution from up to 12 audible walk indications beeping at once and up to 16 constant locator tones at four way intersections with right turn slip lanes; such four way intersections with right turn slip lanes are very common in Sacramento and Davis. Finally, the associated expense of detectable warnings on curb ramps and accessible pedestrian signals may discourage local governments from improving sidewalks and installing new traffic signals at intersections altogether, leading to continuing danger to automobile traffic and pedestrians alike in locations where sidewalks and signals may be most needed.
Again, I believe that, overall, these draft guidelines will provide much needed access for the disabled to pedestrian rights of way. I believe that they will implement positive change. I do believe, though, that the scope and restriction of the guidelines regarding detectable warnings and accessible pedestrian signals must be carefully re-considered. Finally, I thank the Board for this opportunity to comment on these guidelines and for taking the time to read my comments carefully and thoughtfully.
Nathanael T. Wales
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