Robert C. Wunderlich, P.E.
|October 28, 2002|
City of Garland, Texas
Re: Proposed Accessible Public Rights-of-Way Guidelines
I have reviewed the proposed Accessible Public Rights-of-Way Guidelines prepared by the Advisory Committee and find that many of the provisions are impractical and unnecessary. Agencies such as ours work diligently to build new streets and reconstruct old ones in a way that provides accessible routes, but these guidelines will decrease the amount of accessible routes we can build by making it so expensive and onerous to build and reconstruct streets, particularly if an alternate circulation path must be provided during construction. How is it in the best interest of the public to reduce the amount of new construction that makes routes more accessible?
I also find it unfortunate that the Board seems to have adopted a philosophy that motorists cannot avoid striking pedestrians unless every movement is controlled by a device. This philosophy is particularly evident in the requirement for every turn lane at a signalized intersection to be independently signalized and for all roundabout movements to be signalized. The former increases delay and the latter requirement renders roundabouts useless as an alternative to signalized intersections.
Transportation engineers have proven their ability to provide safe and efficient movements for both pedestrians and motorists when given guidance and information about what the goal and needs are. These “guidelines” are too specific and contain hard and fast dimensions that will be impractical to implement. The public as a whole would be better served with a set of actual guidelines more in keeping with those in the Manual on Uniform Traffic Control devices which provide the information and flexibility that allow engineers to engineer practical, cost-effective solutions.
My comments about specific provisions are organized by the section numbering system used in the Draft Guidelines.
Section 1102.3 Alternate Circulation Path
It should be understood that this alternate path may not be immediately adjacent to the path under construction and that if no pedestrian route is provided during construction, an accessible route need not be established either. Streets are rebuilt each year in constrained right-of-ways. It is not practical or desirable to obtain additional right-of-way for temporary access routes. Agencies should be allowed to work with persons with disabilities to find access solutions, as they do now, rather than have a blanket requirement to provide an alternate path made for every project, whether a need is established or not. This provision will make street reconstruction impractical. The irony is that these reconstructions correct existing access deficiencies and implementation of these rules is likely to reduce the number of financially feasible projects.
Section 1102.6 Curb Ramps and Blended Transitions
The guidelines presume the existence of a marked crossing when, in fact, most street crossings are unmarked.
Section 1102.7.2 Informational Signs and Warning Signs
The guideline requires compliance with section 703.5, which specifically provides Braille standards, yet the Discussion of Provisions section states that Braille will not be required. Providing Braille on signs that are likely to be mounted a minimum of 7 (seven) feet from the ground is not likely to provide any useful benefit. The reference to Section 703.5 should be deleted.
Section 1103.4 Cross Slope
The 1:48 maximum cross-slope is impractical at driveways with grades steeper than 2%. This requirement essentially requires construction of a speed hump across every new or reconstructed driveway. The resulting inefficient vehicle maneuvers will increase rear-end collisions along roadways. The sidewalk/pedestrian access route will have to be taken onto private property to make this work at all, and that is not practical in the case of already developed land and, in the case of developing property, will have significant negative impacts on the configuration of the development.
Section 1102.13 Bus Stops
Sections 810.2 and 810.3 cannot be found in the proposed ADAAG guidelines. Perhaps these should be section 1002.2 and 1003.2.
Section 1102.14 On-Street Parking
There does not seem to be a basis for this requirement. Why should the requirement be vastly different for public right-of-way than for building sites? Many block faces have very few parking spaces in the first place and the requirement that each block face have at least one accessible space will result in an allocation of accessible spaces disproportionate to the demand for those spaces. This requirement penalizes motorists that cannot use the accessible spaces. This is particularly a concern in downtown areas where demand for parking outstrips the supply and the impact is exacerbated by the fact that each accessible space will consume two standard spaces. The Board’s assertion is that this will be easier to implement and enforce. This is certainly not the case for the agencies responsible for the right-of-way itself. A proportional requirement seems to be the only fair and practical way to provide accessible parking spaces and the agency should be allowed to determine how best to implement them, without disruption to the normal flow along pedestrian routes.
Are these requirements intended to apply only for areas with marked on-street parking? Surely the Board does not intend for every block face in a residential subdivision to have an accessible space. These should be handled as part of the building site requirements. Public agencies do not have the resources to maintain pavement markings and signs on every block face on every street, nor are they necessary to provide reasonable accommodation of persons with disabilities.
Section 1103.3 Clear Width
Why is the minimum clear width for a pedestrian access route greater than the requirement for accessible routes on sites? No explanation is given in the Discussion of Provisions although this discrepancy is pointed-out.
Section 1103.5 Grade
The specific requirements for ramp grades in Section 405 should be repeated here without having to look them up in another section.
Section 1104 Curb Ramps and Blended Transitions
The illustrations provided in the Discussion of Provisions indicate that actual curb return conditions have not been considered in the development of the Guidelines. All sidewalks are not built immediately adjacent to the street curb and the radii used on even the lowest speed roadways are considerably larger than those shown in the illustrations. Real work and research is needed to develop practical designs that provide accessibility without requiring vastly larger rights-of-way than are commonly required. This is especially critical for reconstruction projects when obtaining additional right-of-way is costly and likely to create disruptions for the adjacent land use.
Do the rules intend to prohibit the construction of a blended transition on a street with a grade greater than 2 percent?
Section 1105.2.2 Cross Slope
A careful and considered analysis of this requirement should be made to examine the consequences of creating “tabled areas” at each and every crossing of one street and another on street design and vehicular movement. On streets with steep grades, it may not be possible to provide a street with a consistent design speed and meet this provision.
Section 1105.3 Pedestrian Signal Phase Timing
It is not necessary to include the entire crosswalk width in the calculation of crossing time. It is sufficient to get the pedestrian to the middle of the last lane. The green signal is not a command to go to the motorist; rather, it is a signal to proceed as a reasonable and prudent person would, which does not include striking a pedestrian. Undoubtedly, a three foot per second walk pace will accommodate a broader range of pedestrians and a 2.5 foot per second would accommodate even more, but shouldn’t the rate be based on empirical statistics rather than the Board’s discretion, especially when the Board’s own committee recommended a speed of 3.5 feet per second? The MUTCD provides flexibility for engineers to tailor the timing to the specific circumstances at each particular location and the ADA requirements should mirror those instead of mandating more restrictive regulations that create more delay for all system users, even when there is no need to. The combination of additional length and slower walk speed can result in a 40% increase in the pedestrian clearance phase at a typical arterial street. When this time is not truly needed by a pedestrian, the extra delay is borne by the motorists.
Section 1105.6 Roundabouts
The provisions contained in these guidelines will ensure that no roundabout will ever again be built in the United States of America. Perhaps we, as a society, will eventually come to this conclusion due to accessibility issues, but it should come after a full and vigorous examination and discussion of the problems and potential solutions, not as a dictate from this Board. Alternatives to crossing at the roundabout exist and midblock crossings in advance of the roundabout should be considered as an alternative pedestrian path for all pedestrians. The requirement for barriers and signals negates any advantage the roundabout has in providing low-speed, low-delay traffic movement. All movements at all entries and exits will have to be stopped in order to allow a single pedestrian movement across any of the approaches, and this will cause the roundabout to operate more inefficiently than a signalized intersection.
Section 1105.7 Turn Lanes at Intersections
Requiring a traffic signal at turn lanes at intersections negates any possibility for yield control of that movement and will result in thousands of lost hours to delay. The only time a green will be displayed is during the green phase for the adjacent parallel movement. Aren’t motorists accountable and responsible for not running over pedestrians regardless of the traffic control or ability of the pedestrian?
Section 1106 Pedestrian Signal Devices
It is difficult to comment on the true impact of these guidelines because examples of the resulting devices are not provided. The guidelines only offer device specifications, not design guidance.
Why is it necessary to separate the two push buttons by 10 feet? Enough information in the form of arrows and cross street names is required to distinguish between the two push buttons. Making them 10 feet apart would seem to add to the confusion, not minimize it. Why not have both on the same pole with enough information provided to distinguish between the two, including the vibro-tactile feature to distinguish between the two directions. Requiring two poles clutters the intersection and makes compliance difficult. Most intersections already have a plethora of poles and other street furniture. Specifically prohibiting co-location of the indicators on a single pole contributes to the profusion of poles and other obstructions.
The distance requirements lack the flexibility necessary to deal with the varying conditions found in the field. A performance requirement or statement of intent would serve the public much better than the rigid dimensions in the Draft Guidelines. Specific circumstances may not allow strict adherence to these dimensions but good engineering could still allow the intent of the guideline to be met or even provide a better solution than strict adherence would allow. The guidelines should provide guidance to allow engineers to design an accessible system.
Robert C. Wunderlich, P.E.
Managing Director of Transportation,
Engineering, Streets and Stormwater
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