William B. Wilson, P.E.
|
October 28, 2002 |
MEMORANDUM
Subject: 36 CFR Parts 1190 & 1191 {Docket No. 02-1] RIN 3014-AA26, Draft
Guidelines
Americans With Disabilities Act
We thank you for this opportunity to comment on this draft of the long awaited
accessibility guidelines for public rights-of-way. We appreciate the challenge
in attempting to develop these guidelines. The Wyoming Department of
Transportation is committed to the task of providing accessibility throughout
our facilities and the comments which follow come from many years of attempting
apply standards and guidelines to new facilities and the more challenging
existing infrastructure.
AASHTO "Comments and Recommendations on the Draft Guidelines for Accessible
Public Rights-of-Way":
The Wyoming Department of Transportation strongly endorses AASHTO's
comments and recommendations and although not
duplicated herein, should be considered a part of our official response.
General Comments:
It is difficult to review this document when it repeatedly makes reference to
other sections of ADAAG using a numbering system which currently does not exist.
We don't take issue with the new numbering system, but cannot fully
cross-referenced guidelines from other sections.
The overall structure of Chapter 11 is more difficult to understand and
interpret than previous versions. The preceding text "Draft Guidelines for
Public Rights-of-Way: Discussion of Provisions" was very helpful to understand
portions of the technical sections and as a minimum should be included as a
commentary with Chapter 11 unless Chapter 11 is re-written. Far more
illustrations need to be added to Chapter 11 as well.
Blended Transitions (1104.2.3):
Blended transitions need to be defined to better understand their purpose.
Minimum Clear Width (1103.3):
A 48" minimum clear width for a pedestrian access route should be desirable
(actually, 60" as AASHTO recommends is better) however there are numerous
existing facilities where site infeasibility makes this difficult to achieve and
the previous standard of 36" provided an acceptable threshold. Perhaps language
should be provided for an exception to 36" in existing facilities.
Curb Ramps (1104):
Although the commentary discusses the importance of dual wheelchair ramps at
intersections, Chapter 11 only provides technical requirements for curb ramps.
We believe there are strong merits for separate ramps, not only for disabled,
but for queuing other pedestrians as well. Chapter 11 should strongly recommend
dual perpendicular ramps, but permit diagonal ramps when compelling reasons or
site infeasibility dictates a lesser standard. Building a single diagonal ramp
rarely takes more right-of-way than dual ramps, but there may be factors such as
drainage features, light poles, etc, which may make a single ramp work better.
Previous versions of this chapter preferred perpendicular ramps vs. parallel
ramps as well they should for drainage problems. Again, Chapter 11 only gives
the technical requirements, and not the warrants for use of parallel ramps.
Furthermore, there should be discussion of whether a single parallel ramp should
be provided vs. two parallel ramps which might have disabled persons going down
and up and down and up going around a corner. Chapter 11 needs to give guidance
on good design in altered facilities and not just serve as a set of inflexible
standards.
Detectable Warnings (1104.3.2):
This issue stands in major controversy and needs to be resolved before
widespread use of such features is required. The temporary suspension for such
devices needs to be reinstated. Currently, the 1991 standard is back in force
after July, 2001. Although the proposed standard is a vast improvement over the
1991 standard, technically the 1991 standard is in force since the proposed
standard is yet to be adopted. This currently puts transportation authorities at
risk of building infrastructure which may be detrimental to one portion of the
disabled community and not help the visually impaired to the extent desired. The
visually impaired community is split on this issue, with many feeling it is not
a cost effective treatment.
Detectable warnings have always been a concern to northern states which
experience snow and ice conditions. Snow and ice removal, tripping, difficult
wheelchair movement, construction tolerances, long term durability are among the
areas of concern. Although the Access Board issued a report "Detectable
Warnings: Synthesis of U.S. and International Practice" this document fails to
alleviate fear of operational and maintenance problems once widespread use of
these devices is achieved.
To be effective, these devices must be constructed to some demanding tolerances.
Too shallow they may not serve as detection to visually impaired. Too aggressive
and they may become tripping hazards or wheelchair impediments. Although there
are many pre-constructed devices, if they are not of the appropriate type or
design, they may not endure in the environment and deteriorate and even further
impede pedestrian traffic. Choosing the right treatment and insuring it is
installed correctly may be problematic for widespread use. DOT's need better
assistance in writing good generic specifications to address these issues. The
fact that there are now many products available may increase the likelihood the
wrong treatments are used or improperly installed.
Cross-walks ( 1105.2):
The width of 96" may be excessive and encourage motorists to encroach more into
crosswalks. This should be made desirable criteria. If this is changed, it needs
to be changed in the MUTCD.
A minium cross-walk cross-slope of 1:48 may be very difficult if not impossible
to achieve particularly in existing facilities. The cross slope of the crosswalk
becomes the longitudinal slope for the adjacent roadway. Forcing a 2% (1:48)
cross slope may cause geometric problems for the roadway. This should be made
desirable criteria.
Missing Driveway Criteria:
Discussion of driveway cuts through sidewalks should be included with viable
options presented as in previous drafts of the guidelines.
Pedestrian Overpasses and Underpasses (1105.5):
The requirement for elevators when the elevation changes for underpasses and
overpasses exceeds 60 inches is desirable, but not practical and in most cases
is technically infeasible. In rural states such as Wyoming and in other
environments as well, these structures would become totally infeasible, not only
because of the additional cost to construct but more fully due to the fact that
these elevators couldn't be properly maintained. This could pose a serious risk
to the users of those elevators.
Many underpasses are constructed as part of a bicycle facility (shared use
path). With this restriction, grade separated paths would become impractical in
many cases. Often drainage facilities are modified to accommodate bicycles since
the cost of new structures is not feasible.
If this restriction leads to the reduction in grade separated pedestrian ways,
this adversely affects those disable persons who could make use of such
facilities.
Roundabouts (1105.6):
The requirement for barriers or similarly distinct elements at prohibited
crossing areas at roundabouts seems unnecessary and may actually result in other
problems. If a crossing is not desired, a vertical curb would be present to
discourage pedestrian crossings, as is the case for many other street
situations. Visually impaired pedestrians should have some kind of awareness of
the areas in which they travel and know they are in the area of a roundabout
where unauthorized crossings should not be attempted.. The use of detectable
warnings should be provided in these situations for curb ramps.
Accessible Pedestrian Signal Systems (1102.8, 1106):
We are aware there are conflicts by different groups with disabilities which
should be resolved before establishing these guidelines.
Detectable Warning Surfaces (1108):
See comments for Detectable Warnings (1104.3.2) made earlier in this document.
Again, our main concern is with the constructability and maintainability of
these features so they perform their intended function without causing reduced
accessibility or hazardous circumstances for others.
On-Street Parking (1109):
ADAAG requirements for accessible parking require a maximum slope in any
direction of 1:48. There is no specific mention of that requirement in this
section. This is interpreted to mean that this requirement does not exist due to
the problems in providing a level area when the street grade is steeper than 2%
or the cross-slope of the roadway is greater than 2% (usually caused by pavement
overlays). Specific language should express this exception so others do not
interpret the 2% (1:48) to be a mandated requirement would be technically
infeasible to provide in many cases.
William B. Wilson, P.E.
Standards Engineer
Wyo. Dept. of Transportation