Harold Lasley
|
October 28, 2002 |
Subject: Draft ADA Standards for Public Rights of Way Accessibility Guidelines
Multnomah County Land Use Planning and Transportation Division appreciates the
opportunity to comment on proposed ADA guidelines for Accessible Public
Rights-of-Way. We appreciate the importance and necessity for these guidelines
in making the street environment safer and more accessible for persons with
disabilities
We have reviewed the draft standards and considered how they would affect the
programs and services that our Agency provides. We do not want to overemphasize
the financial impact of the proposed standards; however, the financial impact
cannot be ignored. For some projects, the additional cost imposed by the
standards would be minimal. However, the cumulative effect of some aspects of
the guidelines will result in substantial increases in project costs and fewer
projects being performed within current funding levels. We provide examples of
such situations in the comments that follow.
As a general comment, we believe it would be very useful to professional
designers, if the standards and guidelines were delineated in a manner that
utilized and differentiated the terms standard, guidance, and option.
To this end, we recommend that the Access Board consider The Manual on Uniform
Traffic Control Devices (MUTCD) as a model for this approach. By differentiating
between standard, guidance, and option, the MUTCD provides standards and
flexibility to the professional design community that promote uniformity on key
elements of the system, yet allow for innovative solutions to specific site
conditions. Without additional flexibility, the draft ADA standards run the risk
of being too prescriptive, inhibiting innovative and cost-effective solutions to
accessibility issues.
Flexibility needs to be maintained because local topography presents unique
design challenges that cannot be fully envisioned and addressed when preparing
general design standards. If flexibility is too narrowly constrained, then
applying the guidelines will be extremely challenging because of the variety of
site conditions encountered.
Letter/Access Board
Page 2
Following are several additional comments and suggestions we recommend for
consideration of the Access Board. In some cases, we have presented these as
statements and recommendations. In other cases, we have presented these as
questions that we ask for the purpose of clarification.
Existing Public Rights of Way (1102.2)
The guidelines seem to divide improvements into “additions” and “alterations.”
We suggest that additional guidance be provided on the differences between
additions (new construction) and alterations and when certain provisions apply.
1102.2.2 states, “Where existing elements or spaces in the public right-of-way
are altered, each element or space shall comply with the applicable provisions
of Chapter 11.” The addition of the word “space” causes some additional
confusion. We offer the following situations and ask whether these are
interpreted to be “alterations” or “additions.”
• Example A: A corner is proposed to be reconstructed to install curb ramps.
Ramps can be constructed at appropriate grades and widths.
o Suppose the landings will be too small unless the signal pole and pushbuttons
are relocated. If the signal pole cannot be relocated without right-of-way
acquisition, does that constitute “technical infeasibility?”
o If the signal pole and push buttons are relocated to allow appropriate ramps
and landings, do provisions of 1106.3 Pedestrian Pushbuttons apply because the
signal was altered?
o Does the alteration of the corner (arguably a “space”) require meeting the
provisions of 1106.3 even if the poles and signal system are not otherwise
altered?
• Example B: A new intersection is created where a subdivision street is
designed to intersect with an existing arterial street. The existing grade of
the arterial street is 6 percent. Given that the existing arterial has a grade
of 6 percent, sidewalks along the arterial can match that grade. However, the
new subdivision will create a new intersection and new crosswalks.
o Are the new intersection and the new crosswalks required to meet the 1:48 (2
percent) slope requirements for both cross slope and running slope?
o If “yes,” how do we deal with the steeper section along the arterial caused by
flattening the intersection?
o Does the answer change if the arterial street has an underlying grade of only
4 percent?
We support the exception for alterations based on a determination that they are
“technically infeasible.” We suggest that there should be exceptions for new
construction based on “technical infeasibility.” We are not, however, suggesting
that the standards for determining feasibility should be the same for
alterations or additions.
Letter/Access Board
Page 3
Alternate Circulation Path (1102.3, 1111)
We support the provision of a signed alternate circulation route during
maintenance and construction activities. However, we would like to see a degree
of flexibility and a provision for exceptions to this requirement where it is
not feasible for safety reasons.
Multnomah County has many roadways with five motor-vehicle lanes, bike lanes and
five-foot curb-tight sidewalks. When we repair or make improvements to the
sidewalk, we often have to close the curb lane for the construction activity.
The lane is occupied by backhoes, dump trucks, concrete trucks, etc. When space
behind the sidewalk is not available, the alternate circulation path would have
to be moved into the second motor vehicle lane. With sufficient barricades and
markings, this could be made safe, but it could not be easily re-established
each workday and would have to stay in place from the beginning of the project
its end. The resulting closure of two lanes in the same direction would require
shifting the on-coming traffic to a single lane. Even if this proved feasible in
mid-block locations, it would be especially difficult at intersections. Shifting
motor-vehicle traffic two lanes to the left would likely put them out of the
cone of vision for the existing traffic signals and could potentially require
flaggers for the operation of the intersection. Such changes in traffic
operations would significantly reduce intersection capacity and quite possibly
make it impossible to give pedestrians access to push buttons to actuate the
WALK signal. In this example, providing an adjacent alternate circulation path
could create a public safety problem for both pedestrians and motorists.
The draft guideline is too prescriptive in our opinion. We suggest the standard
be the provision of a safe alternate circulation path and the guidance should
give preference to a route that does not involve a shift to the opposite side of
the street or other circuitous route. Reducing adverse impacts to persons with
disabilities is an important consideration during construction and maintenance
activity. However, in some cases, a short-term interruption of access may be
safer and more prudent than an alternate circulation path for an extended
period. The proposed guidelines do not allow design professionals or even policy
makers,who are ultimately responsible for balancing the needs of all
transportation system users, to make that decision.
Section 1111.5. This also makes reference to a “disrupted pedestrian access
route.” We are uncertain of the meaning of this. Does a “disruption” refer to an
alternate circulation path, a closure, or something else entirely?
Protruding Objects (1102.5). This section limits the protrusion to 4 inches for
any object between 27 and 80 inches above the surface. We note that the MUTCD
provides for traffic signs to be mounted 7 feet above the pavement and for
supplemental signs to be mounted up to one foot lower. Multnomah County makes a
special effort to ensure that our signs meet these mounting heights. The typical
supplemental sign mounted as little as 6 feet above the sidewalk is a 12-inch by
18-inch “NO PARKING” sign. Since the nominal 4x4 post on which we mount signs
measures only 3-½ inches, our signs protrude 4-¼ inches into the sidewalk area.
For agencies that use 2-inch channel or pipe, the protrusion would be 5 inches.
We recommend that the protrusion standard be reviewed to see, if slight
modifications would be appropriate to allow sign-mounting practices allowed in
the MUTCD to continue.
Letter/Access Board
Page 4
It appears that the protrusion aspects of the guidelines would allow
downward-sloping guy wires that run parallel with the sidewalk, but would
clearly preclude them from crossing a pedestrian access path. Is it appropriate
to allow downward-sloping guy wires anywhere along the pedestrian path?
Pedestrian Access Route (1103)
Clear Width (1103.3). This section specifies a minimum clear width of 48 inches.
We agree with this specification, but suggest it should be modified to increase
the minimum to 60”, where bollards or similar devices are installed specifically
to restrict motor-vehicle entry.
Surface Gaps at Rail Crossings (1103.7). We support the concept of minimizing
gaps at rail crossings. We suggest the Board consider the implications of
crossings that occur at angles other than 90 degrees. This may be more important
than the gap measurement itself.
Detectible Warnings (1103.7.1). We find this confusing. Does this section mean
that a sidewalk adjacent to a road does not require a surface warning treatment
at a rail grade crossing? Or is “detectible warning” something different in this
context?
Pedestrian Crossings (1102.8, 1105)
Crosswalks (1105.2). The running slope and cross slope requirements may result
in a significant increase in road maintenance costs for pavement overlays and
strengthening. A widespread pavement overlay technique is to place a greater
asphalt depth in the center of the road and a lesser depth at the gutter. This
technique increases the strength of the pavement where traffic loads are
greatest and avoids the cost of removing pavement at the pavement edges where
adequate curb exposure must be maintained. However, since this technique
increases the crown of the road, it could cause a road to exceed the proposed
slope requirements. The more expensive and time-consuming method involves
grinding and removing the existing pavement surfaces. Grinding and removal of
existing pavement can result in pavement damage that must be repaired, reduced
pavement strength, and more frequent pavement treatments. The guidelines as
drafted will have this effect.
We recommend that slope requirements specified in the proposed rules apply to
new construction only and that a slightly greater slope be allowed on existing
roadways in way that allows some flexibility for road maintenance overlays.
Communities located in areas with steep topography will not be able to meet the
proposed cross slope requirements without extensive alteration of existing
roadways. We recommend that topography and slope of the underlying terrain be
specifically mentioned as exceptions, based on a finding that compliance is
technically infeasible.
Pedestrian Signal Phase Timing (1105.3). We believe it is overly restrictive to
require the pedestrian clearance time be calculated using a pedestrian walk
speed of 3.0 feet per second. We fully support the use of that speed where the
need is apparent and we currently use such a speed in our calculations where we
have observed or had requests for an extended clearance time. We
Letter/Access Board
Page 5
have found that longer pedestrian change intervals can completely disrupt signal
timing progression in major corridors and can cause substantial increases in
delays for both major street and minor street traffic. These factors can reduce
overall system efficiency and increase air pollution. Longer cycle lengths may
also increase the incidence of running red lights by motorists and decreases in
safety.
We recommend that 4.0 feet per second be retained as the standard, but that
guidance be provided with a lower walking speed (3.0 feet per second) where
conditions warrant that based on engineering judgment.
Surfaces (1104.3). The proposed guidelines prohibit gratings, access covers,
and/or other appurtenances in curb ramps, landings, blended transitions, and
gutter areas within pedestrian access routes. We agree with this in concept, but
find there are so many conflicting needs at corners that our options are
severely limited with regard to placement of traffic signal junction boxes at
signalized intersections. We suggest that leeway be allowed to place access
covers in landings, if it is not practical to locate them elsewhere. We support
the prohibition of such items in ramps, transitions, and gutter areas.
Pedestrian Overpasses and Underpasses (1105.5). The guidelines propose
requirements for an elevator where the rise of ramped approach exceeds 60
inches. We find this far too restrictive and believe it will be a deterrent to
constructing under- and overpasses for improved pedestrian movement.
There appears to be an inconsistency between section 1105.5.2, which specifies
that the running slope shall not exceed 1:20, and 1105.5.3, which applies when
the slope exceeds 1:20. We suggest this inconsistency be resolved or explained.
We also question whether 48 inches is an adequate minimum width for an approach
unless it is for a very short length.
Roundabouts (1105.6). The proposed requirements for pedestrian activated signals
severely compromises use of a roundabout as a means of accommodating traffic at
an intersection. We urge further research and evaluation be conducted. We
suggest that different treatments may be appropriate depending upon the number
of approach lanes and the design speed used for individual roundabouts.
Accessible Pedestrian Signal Systems (1102.8, 1106)
There are many conflicting requirements and site conditions at intersections
that the professional designer must address to provide safe and convenient
pedestrian crossings. The proposed guidelines significantly restrict the ability
to optimize a design that best meets the constraints encountered. While we
understand the rationale for most of the elements individually, we are concerned
about their interrelation and our ability to meet all of them simultaneously,
especially in situations where topography and right-of-way limitations severely
limit the options.
Letter/Access Board
Page 6
Location (1106.2.1). The concept of separating the individual signal access
buttons by a distance of 120 inches is questionable based upon local
observations. We think this will be very difficult to achieve at any
intersection where there is significant grade on either road approach. The
proposed guideline of separating the signal access buttons on individual
pedestals 120 inches apart is not uniformly endorsed by the disabled community
as an enhancement for coping with crossing a congested intersection. We
recommend that the Board carefully review this guideline and solicit additional
input from the disabled community. The single-pedestal design standard currently
being used in Multnomah County appears to be very functional and provides good
service to the disabled community.
This section also requires that the control face of the device face the
intersection and be parallel to the crosswalk it serves. We prefer this location
and orientation, but find this requirement to be very limiting. We recommend
that the side-mount orientation (perpendicular, rather than parallel) also be
permitted as long as visual and tactile explanations are provided for that push
button. Our concern is that terrain and other space limitations may preclude the
prescribed orientation when combined with the required size and slope of
landings and ramps.
The requirement that the push buttons be located between 30 inches and 120
inches behind the curb will be problematic, especially where a street has a
considerable grade. The 120-inch maximum gives little leeway, especially when it
is combined with the required button orientation. A seven-inch curb requires a
ramp with a minimum length of 84 inches. Adding a 48-inch landing allows only 12
inches within which to locate the button. Due to conflicts with underground
utilities and other immovable obstructions, we find it difficult to place our
signal poles with this level of precision. We recommend that this spacing
requirement be softened to a recommendation status rather than a requirement
implied by the word “shall.”
Volume (1106.2.3.2). The requirement for the volume to be responsive to ambient
noise-level changes may be problematic. We suggest the requirement be softened
from the mandatory “shall” to the suggested “should.”
Multnomah County is supportive of the effort to improve accessibility to the
transportation system for all our citizens. We support the effort to standardize
the systems to make it easier for persons with disabilities to navigate our
community. We applaud the Access Board’s efforts to provide guidance. We ask,
however, that the Board give more consideration to the difficulties of
implementing some of these concepts, especially as they relate to the
variability of terrain with which we have to work. We specifically ask that the
Board revise the guidelines to clearly differentiate between standards that must
be achieved and those areas where a little flexibility can be granted.
Sincerely,
Harold Lasley, P.E., Director
Multnomah County Transportation Division