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.
Sincerely,
Robert C. Wunderlich, P.E.
Managing Director of Transportation,
Engineering, Streets and Stormwater