Brant Williams, P.E.
|
October 28, 2002 |
Comments of the Draft Guidelines
Portland Office of Transportation
Brant Williams, P.E.
Director
1101 Application and Administration
1102 Scoping Requirements
1102.1 General. All areas of newly designed and newly constructed facilities in
public rights-of-way and altered portions of existing facilities in public
rights-of-way shall comply with Chapter 11.
1102.2 Existing Public Rights-of-Way. Additions to existing public rights-of-way
shall comply with 1102.2.1. Alterations to existing public rights-of-way shall
comply with 1102.2.2.
1102.2.1 Additions. Each addition to an existing public right-of-way shall
comply with the applicable provisions of Chapter 11. Where the addition connects
with existing construction, the connection shall comply with 1102.2.2.
PDOT COMMENT: Recommend that this term be deleted because it does not add any
clarity to the draft regulation. Keep just two terms in this section: NEW
CONSTRUCTION and ALTERATIONS.
1102.2.2 Alterations. Where existing elements or spaces in the public
right-of-way are altered, each altered element or space shall comply with the
applicable provisions of Chapter 11.
EXCEPTION: In alterations, where compliance with applicable provisions is
technically infeasible, the alteration shall comply to the maximum extent
feasible.
PDOT COMMENT: Both “technically infeasible” and “maximum extent feasible” need
to be clearly stated in 1101.3 Defined Terms.
1102.5 Protruding Objects. Protruding objects on sidewalks and other pedestrian
circulation paths shall comply with 1102.5 and shall not reduce the clear width
required for pedestrian accessible routes.
PDOT COMMENT: The end phrase of the above sentence should be corrected to read "
... pedestrian access routes."
1102.5.2 Post-Mounted Objects. Free-standing objects mounted on posts or pylons
shall overhang circulation paths 4 inches (100 mm) maximum when located 27
inches (685 mm) minimum and 80 inches (2030 mm) maximum above the finish floor
or ground. Where a sign or other obstruction is mounted between posts or pylons
is greater than 12 inches (305 mm), the lowest edge of such sign or obstruction
shall be 27 inches (685 mm) maximum or 80 inches (2030 mm) minimum above the
finish floor or ground.
PDOT COMMENTS: The proposed standard for a 4 inch projection of a sign from its
post will have significant impact on communities across the country. The MUTCD
standard for parking control signs are 12 inches wide signs mounted on a 2-3/8
inch diameter sign pole. This results in a 4.81 inch projection from the outside
of the pipe to the outer edge of the sign. The draft rule will require the
modification of the current industry standard because the projection is a little
over ¾ inch too wide. All future signs would need to be manufactured to be not
wider than 10-3/8 inches wide. The new standard sign, 1-5/8 inches narrower than
the current industry standard, will have consequences than extend to
manufacturing of aluminum, steel, and plastic sign blanks. Existing silk screens
used to paint signs would need to be discarded. Reflective sign legends that are
applied with a contact glue to the sign blank will also need to be redesigned by
manufacturers of this material. PDOT recommends that a 5 inch projection
standard be considered.
The second sentence is not clear in its application. We assume that the Board
means that where signs have multiple posts or pylons that are spaced more that
12 inches apart, this configuration should not be detrimental to blind
travelers. The Board should follow the PROWAAC recommendation and require a
detectable horizontal element set at 15 inches above the walking surface between
the multiple posts or pylons. If the multiple post configuration is cane
detectable, signs could be mounted at any vertical location between the posts or
pylons.
Some agencies utilize a vertical sign structure consisting of vertical,
horizontal, and diagonal elements that are attached together to form a truss or
frame. Signs can be mounted from the walking surface to the top of the
structure. If this vertical sign structure is detectable, it should not be a
problem for blind travelers.
EXCEPTION: This requirement shall not apply to sloping portions of handrails
serving stairs and ramps.
1102.14 On-Street Parking. Where on-street parking is provided, at least one
accessible on-street parking space shall be located on each block face and shall
comply with 1109.
PDOT COMMENTS: This requirement means that at least one accessible on-street
parking space be provided on every single newly constructed block face. This
requirement is problematic for several reasons. First, using the measurement of
“block face” as its basis will result in an inconsistent application of this
requirement. The City of Portland typical block face is 200 feet. However, we
also have super blocks where the length of the block face may be 3 or 4 times
the typical block. Also, block sizes can vary greatly from city to city. Block
faces are an inappropriate unit of measurement for determining the number of
accessible on-street parking spaces. We would recommend that a more appropriate
unit of measure be used such as the total number of on-street parking spaces or
possibly lineal feet of street.
Secondly, given the small block sizes in Portland, the number of accessible
parking spaces compared to the total number of spaces on the block face is
excessive. Best case scenario in our downtown, we can provide 9 on-street
parking spaces per block face. However, on average, this number is significantly
less due to driveways, loading zones, curb extensions at corners, etc. The
average is more likely to be around 6 spaces per block. Providing one accessible
space for every 6 on-street spaces is again excessive. We would recommend that
this rule be consistent with the requirements for private parking areas; i.e. a
similar proportion of accessible on-street spaces to the total number of
on-street spaces for both off-street and on-street parking areas.
Thirdly, as it reads, this rule includes all residential streets as well as
other classifications of streets. This appears to be an oversight in writing the
draft guidelines.
And lastly, the original Section 14 and the recommendations of PROWAAC limit
this requirement to central business districts of cities. We recommend that this
requirement be revised to include the provisions identified both in Section 14
and the PROWAAC report.
1103 Pedestrian Access Route
1103.8 Changes in Level. Changes in level shall comply with 303. Changes in
level shall be separated horizontally 30 inches (760 mm) minimum.
PDOT COMMENT: This proposed standard needs to be more clearly defined in its
application. Consider changing the term “changes in slope” because all surfaces
in the public right-of-way are actually built on sloping surfaces. Very rarely
in the outdoor environment would one encounter a truly “level” situation.
We assume that the Board is attempting to regulate the frequency of slope
changes or “grade breaks” ( a more common term ) in the longitudinal Pedestrian
Access Route.
EXCEPTION: The horizontal separation requirement shall not apply to detectable
warnings.
1104 Curb Ramps and Blended Transitions
1104.1 General. Curb ramps and blended transitions shall comply with 1104.
1104.2 Types. Perpendicular curb ramps shall comply with 1104.2.1 and 1104.3;
parallel curb ramps shall comply with 1104.2.2 and 1104.3; blended transitions
shall comply with 1104.2.3 and 1104.3.
1104.2.1 Perpendicular Curb Ramps. Perpendicular curb ramps shall comply with
1104.2.1, and shall have a running slope that cuts through the curb at right
angles or meets the gutter grade break at right angles.
PDOT COMMENTS: PROWAAC spend countless hours with the issue of directionality
and it was discussed in 2 pages of the report to the Board. It was not fully
resolved because the needs of the wheelchair users and blind travelers were at
odds. The question that could not be resolved was as follows:
1. Should a perpendicular ramp be aligned with the direction of travel and
benefit the blind and sighted travelers and create a potential problem for
wheelchair users. OR
2. Should a perpendicular ramp be aligned at a right angle to the radius of a
corner to the benefit of wheelchair users and lose a directionality for blind
travelers.
There are many arguments for both cases depending upon which group is being
viewed as receiving preferential treatment. The draft regulation gives
preference to wheelchair users and has the following undesirable impacts:
• Ramp alignment at a right angle to the radius forces the ramp to be skewed
from the direction of travel
• Blind travelers lose directionality that could have been provided if the ramp
were aligned in the true direction of travel. [ We continuously receive comments
from members of our blind community that ramps should be build to align with the
straight direction of travel. ]
• Sighted travelers lose the benefit of the ramp and will encounter a portion of
the curb on the ramp flare if they chose to travel in a straight line. This
creates a tripping hazard for both sighted and low vision pedestrians.
• Ramp alignment on the radius creates a very complicated design and an extreme
construction challenge and contributes significantly to the design and
construction cost of each ramp.
• Ramp alignment on the radius calls for shifting the ramp a few feet left or
right of the true direction of travel. This realignment does not improve
cross-slope and warping problems. Most ramps will have some warping between the
level landing and the street gutter because the outdoor environment is rarely
level.
• Ramp alignment on the radius has a poor architectural appearance and violates
“form” without contributing to improved “function.”
• Wheelchair users need to take an out of direction travel path upon leaving the
landing to proceed down the ramp and enter the crosswalk. They then need to make
another direction change to align with the crosswalk direction of travel. This
path of travel resembles an “S.”
• Persons with limited mobility skills that tend to shuffle as they travel, will
need to follow an “S” path of travel to utilize the benefit of a curb ramp and
avoid the vertical rise of the curb in the flare section of a ramp when it is
aligned on the axis of the radius
We feel that the Access Board should abandon the right angle with radius
alignment requirement or better yet, support the ramps being aligned with the
direction of travel. The very worst thing that could happen is that wheelchair
users would make the smaller “S” path of travel as they proceeded down the ramp
to allow the wheelchair to align the front caster wheels at a right angle with
the street gutter. All other users, blind, low vision, persons with limited
mobility skills, and sighted pedestrian would benefit from the ramp being
aligned with the direction of travel.
1104.2.1.4 Flares. Flared sides with a slope of 1:10 maximum, measured along the
curb line, shall be provided where a circulation path crosses the curb ramp.
PDOT COMMENT: The term slope is erroneous because in infers that one of the
components is dead level. This does not happen in the public right-of-way
because unlike the building environment where dead level is common, it rarely
happens in the street area. PROWAAC discussed this issue extensively and came to
the conclusion that the curbed portion of the flare needed to transition from
the curb ramp base [ zero curb exposure ] to the top of the full curb [typically
6 inch exposure] over a ratio of 1 foot vertical to 10 foot horizontal. For a
typical six-inch curb, the length of the flare at the face of the curb would be
sixty-inches, regardless of the slopes of the street or the cross-slope of the
ramp.
This provision can be rewritten as follows: “Curb ramp flares adjacent to curb
ramps that are provided where a circulation path crosses the curb ramp, shall
have the curb exposure, as measured along the gutterline, rise from
zero-exposure at the ramp to full curb exposure on a ratio of 1 foot vertical to
10 foot horizontal regardless of sidewalk or gutter grades.”
1104.2.2 Parallel Curb Ramps. Parallel curb ramps shall comply with 1104.2.2,
and shall have a running slope that is in-line with the direction of sidewalk
travel.
1104.2.2.4 Diverging Sidewalks. Where a parallel curb ramp does not occupy the
entire width of a sidewalk, drop-offs at diverging segments shall be protected
with a barrier.
PDOT COMMENT: It would be far better to not allow this type of curb ramp design
at intersections rather than require a continuous barrier. Since “barrier” is
not defined, we will assume that it means a fence, handrail, roadway guardrail,
raised landscape planter, or any other type of acceptable barrier. A schematic
drawing would be helpful to understand this parallel ramp concept.
At a typical corner where a parallel ramp is used, this regulation would
essentially divide the pedestrian area in half running parallel to the curb as
it curves around a corner. Persons wanting to cross at the intersection must
make a decision on the approach to the corner to chose the “low road” to the
ramp or the “high road” to stay on the sidewalk and avoid the crossing. Those
persons choosing to cross at the intersection must utilize the parallel curb
ramp to reach the crosswalk. This means that all “crossers”, disabled or not,
will need to descend the ramp to the crosswalk.
The divided sidewalk will certainly cause problems for blind travelers because
if they miss the parallel ramp, they could not reach the crosswalk because of
the barrier. Likewise, if the blind traveler did not want to cross the street,
the barrier could divert them down to street level at the crosswalk where they
did not want to go.
This design is also unsafe in that it removes any means of escape for
pedestrians in the event a vehicle cuts too close to the ramp. Without the
barrier, pedestrians that recognize the danger of an approaching errant vehicle
could move to the back of the sidewalk to avoid being injured. With the barrier,
the pedestrian could not move out of harm’s way. In fact, they would be trapped
between the oncoming errant vehicle and the barrier.
In tangent areas, where isolated parallel ramps are the best design solution,
such as access to an on-street disabled parking space from sidewalk level, it
could be beneficial to utilize a barrier. There certainly other examples where a
barrier would be helpful. However, the Access Board must answer the question:
What persons are you attempting to protect? Blind persons using long canes will
likely find the ramp and the adjacent curb and not be in danger. Sighted
persons, including mobility device users, will see the ramp and the adjacent
sidewalk. So who really needs the barrier? The fall into the parallel curb ramp
would be the same as a fall from the curb at sidewalk level to the adjacent
street level. But the Board is not recommending barriers between sidewalk level
and street level.
1104.2.3 Blended Transitions. Blended transitions shall comply with 1104.3, and
shall have running and cross slopes of 1:48 maximum.
PDOT COMMENT: As we understand a blended transition, it is simply a large
landing that runs parallel to the curb radius. This landing more resembles the
landing used on a parallel curb ramp, only that is probably larger and is not
necessarily served by a parallel ramp. It more typically models the street
surface extended into the corner pedestrian area with a drainage slope pitched
to the street.
Because of the running and cross slope limitations, this blended transitions
could only fit if the street gutter grade were 2% or flatter. Further, because
of drainage issues, this type of landing would rarely be used. This blended
transition would afford little protection to pedestrians because it is level
with the roadway and excludes barrier curbs.
We question why the Board would offer this as an accessibility improvement when
it has so many limiting and detrimental characteristics.
1104.3 Common Elements. Curb ramps and blended transitions shall comply with
1104.3.
1104.3.4 Grade Breaks. Grade breaks shall not be permitted on curb ramps,
blended transitions, landings, and gutter areas within the pedestrian access
route. Surface slopes that meet at grade breaks shall be flush.
PDOT COMMENT: The PROWAAC report specifically recommended that where a curb ramp
meets the street surface at the gutter, the two sloping surfaces must be flush
so that there is not a vertical "lip" on the curb ramp. This may be implied in
either 1104.3.4 or in 1104.3.5, but it is not clearly stated.
1104.3.7 Clear Space. Beyond the curb line, a clear space of 48 inches (1220 mm)
minimum by 48 inches (1220 mm) minimum shall be provided within the width of the
crosswalk and wholly outside the parallel vehicle travel lane.
PDOT COMMENT: We understand that this requirement will provide a 4’ X 4’ refuge
area on the street pavement beyond the curb ramp where a pedestrian would not be
struck by parallel traveling vehicles and bicycles. However, geometrically, this
will not always work. Take the case of a small corner radius of 10’ and a
sidewalk built adjacent to the curb. A parallel ramp design is the only possible
alternative. The bottom landing of the curb ramp is centered on the diagonal of
the radius. It is then mathematically impossible to create the refuge area on
the pavement and be wholly outside the parallel vehicle travel lane.
Since a parallel curb ramp already has a level landing / refuge within the
sidewalk and adjacent to the street, we suggest that the clear space requirement
be removed for all parallel curb ramps. If this condition is not removed, the
Board will have automatically excluded parallel curb ramps at corners with a
radius of less than 15’.
1105 Pedestrian Crossings
1105.1 General. Pedestrian crossings shall comply with 1105.
1105.2 Crosswalks. Crosswalks shall comply with 1105.2.
1105.2.1 Width. Marked crosswalks shall be 96 inches (2440 mm) wide minimum.
1105.2.2 Cross Slope. The cross slope shall be 1:48 maximum measured
perpendicular to the direction of pedestrian travel.
PDOT COMMENTS: This one sentence provision potentially has more impact that any
other part of Chapter 11. Without directly stating it, this regulation will
require that all future intersections be essentially flat. Construction of flat
intersections and steep intersection approaches and departures are technically
infeasible, extremely expensive, environmentally unsound, and are in conflict
with safe roadway design.
The outdoor environment, all formed at the whim of Mother Nature, cannot be made
to conform to the indoor environment that man builds. In Portland, as well as
many other cities across this nation, we build streets with centerline grades
that range from 0.5% to as much as 22%. We do this to make the developable land
with the confines of our urban growth boundary available for its highest and
best use. The Tualatin Mountains, within our city limits, rises more than 1000
feet above City Hall and are less than 2 miles from the center of the city. With
terrain like that, it is almost impossible to construct roads that would satisfy
the cross slope criteria of 1105.2.2.
Even if the excessive cost factors were ignored and construction to meet these
standards were attempted, the environmental damage would be staggering. To
create a tabled or flat intersection in hilly terrain, calls for major
excavations into uphill slopes and massive fill sections on downhill slopes. The
combined work for a single intersection could involve the clear cutting of all
vegetation and earth disturbances on at least 2 acres [ 87,120 square feet ] of
land to create one intersection. The resultant “flat intersection” would have
street slopes far steeper that if the roadway were build to conform to the
natural grade of the existing terrain. Disabled persons could certainly be able
to use the intersection but would not be able to get to the intersection or
leave it because the roadway / sidewalk slopes would be too steep.
Flat intersection design requires the use of long vertical curves to smooth out
longitudinal grade breaks. These curves are a function of the roadway speed,
safe stopping sight distance, and roadway running slopes. The length of
smoothing out one intersection will exceed the distance to the next
intersection. This means that the next intersection must be moved farther away
to make the running grades work with the flat intersections. In some cases, this
flat intersection requirement has the effect of eliminating subdivisions on
steep terrain because the land area cannot be reformed to fit the platting of
lots and blocks because “accessible” intersections cannot be designed.
Roadway designers must take into consideration multiple variables that affect
the safe usability of the facilities. These variables include, but are not
limited to: horizontal alignment, vertical alignment, safe stopping sight
distance, existing terrain, environment, design speeds, maximum grades, critical
length of grades, and many others. Roadway alignments with numerous breaks
because of successive intersections is poor design. Although it may be
beneficial to reduce grades at intersections, attempting to make them “flat”, is
flawed design. The Green Book points out that “… the gradeline of the major
highway should be carried through the intersection, and that of the crossroad
should be adjusted to it. This design requires transition of the crown of the
minor highway to an inclined cross section at its junction with the major
highway.” In other words, even on local streets, one street follows the natural
gradeline downhill, and intersecting streets are warped to fit.
EXCEPTION: This requirement shall not apply to mid-block crossings.
1105.3 Pedestrian Signal Phase Timing. All pedestrian signal phase timing shall
be calculated using a pedestrian walk speed of 3.0 feet per second (0.91 m/s)
maximum. The total crosswalk distance used in calculating pedestrian signal
phase timing shall include the entire length of the crosswalk plus the length of
the curb ramp.
PDOT Comment: This requirement could have severe consequences regarding the
timing of signals, vehicular delays, overall congestion, and pollution levels.
In Portland, an intersection that is 60 ft wide (curb to curb) would provide a
pedestrian 15 seconds total clearance interval (flashing don’t walk + yellow)
based upon a crossing rate of 4.0 fps. Under the draft proposal, the same
crossing would need to include the length of the curb ramps (assumed to be 2 @ 5
ft), increasing the crossing distance to approximately 70 ft. If a crossing rate
of 3 fps is assumed, the pedestrian clearance interval would need to be
lengthened to 24 seconds. The additional 9 seconds of clearance time required to
cross slow pedestrians on the one crossing would have a severe impact on
vehicular capacity on the main street if the crossing were a “pedestrian only”
signal or was a location where the parallel traffic movement was very light.
Complaints regarding traffic congestion are common in urban areas such as
Portland. The reduction in the pedestrian crossing rate used to calculate the
timing of traffic signals would undoubtedly result in increased congestion, and
longer delays.
A couple of other unintended consequences of the slower crossing speed could
include shorter “Walk” intervals (the “Walk” phase being shortened to help
absorb the longer “Flashing Don’t Walk phase), and pedestrian pushbuttons where
none currently exist (to avoid serving the ped phase when no pedestrians are
present). Pedestrians who push the pedestrian button and then proceed to cross
the street when an adequate gap occurs are often long gone by the time the
pedestrian phase is served. Providing shorter walk times at locations where
pedestrians may be tempted to cross against the signal indication can help to
reduce unnecessary delay to motorists.
We often hear complaints that the pedestrian crossing time is too short from
pedestrians who do not understand the meaning of the pedestrian signal
indications. Most pedestrians are more comfortable with the pedestrian signal
timing after they are educated on the meaning of the signal indications. Most
complaints are regarding the short “Walk” phases. Few people complain about the
“Flashing Don’t Walk” clearance intervals.
One other consequence of lengthened flashing don’t walk intervals will be
increased non-compliance by the majority of pedestrians. Today we already have a
severe problem with pedestrians disregarding the pedestrian signals. Using the 3
fps rate for the flashing don’t walk lengths will generate crossing intervals
that can be easily met by over 95% of the population. Users will see this
exceeding long length as unnecessary and pay even less attention to pedestrian
signals.
It is our recommendation that the policy be modified to allow agencies to
implement pedestrian crossing times based off of local knowledge using crossing
speeds ranging from 3.0 fps for a disabled person to 4.0 fps for an average
pedestrian. The City of Portland has already made accommodations for slower than
average and disabled pedestrians at several signalized intersections, and would
prefer to work directly with these groups to identify problem locations where
pedestrian needs could be better met. This would allow us to balance the needs
of ALL users of the ROW to maximize the safety and efficiency of the signal for
all users.
1105.4 Medians and Pedestrian Refuge Islands. Medians and pedestrian refuge
islands in crosswalks shall comply with 1105.4 and shall be cut through level
with the street or have curb ramps complying with 1104 and shall contain a
pedestrian access route complying with 1103. Where the cut-through connects to
the street, edges of the cut-through shall be aligned with the direction of the
crosswalk for a length of 24 inches (610 mm) minimum.
1105.4.1 Length. Where signal timing is inadequate for full crossing of all
traffic lanes or where the crossing is not signalized, cut-through medians and
pedestrian refuge islands shall be 72 inches (1830 mm) minimum in length in the
direction of pedestrian travel.
PDOT COMMENT: The meaning of this regulation is not clear and should be revised
to say: “Where pedestrians are expected to wait because signal timing is
inadequate for full crossing of the traffic lanes or where the crossing is not
signalized and a pedestrian must wait for gaps in the vehicle traffic flow, a
refuge area, 72 inches minimum in length in the direction of pedestrian travel
shall be provided in the cut-through median or pedestrian refuge island.”
1105.5 Pedestrian Overpasses and Underpasses. Pedestrian overpasses and
underpasses shall comply with 1105.5.
PDOT COMMENT: This condition is not entirely clear to most readers. There are a
number of situations that need to be evaluated before specific regulations can
be set. Otherwise, the Access Board is attempting to force fit one solution to
fit all situations. A sampling of common overpass / underpass situations is as
follows:
• At-grade intersections where pedestrians are routed over a bridge structure.
These are built in to provide pedestrian only access over a busy arterial
street. A good example is the intersection of the Las Vegas Boulevard [ the
Strip ] and Tropicana Boulevard in Las Vegas, NV. Four separate bridge
structures exist to safely route pedestrians between the various casinos at this
very busy street intersection. All have escalators and elevators.
• At-grade intersections where pedestrians are routed under the roadway through
an underpass or tunnel. Portland used to have several of these pedestrian only
tunnels beneath busy arterial streets. However, most have been closed because
pedestrians felt unsafe using these isolated facilities.
• Grade separated intersections where one street is on a bridge structure and
the other roadway or pedestrian route is below the bridge. In some situations,
pedestrian connections are made using pedestrian stairways between the two
levels. An example of this type of route exists in downtown San Antonio, TX
along the “Riverwalk” where the San Antonio River frontage includes a pedestrian
route.
• Grade separated intersections where one street is in a tunnel beneath the
surface street. Again, in some situations where both streets have pedestrian
sidewalks, the two levels may be connected with pedestrian stairways.
• Pedestrian only connections using stairways between roadways at different
levels. These usually occur in areas with steep terrain. These stairways usually
create a non-accessible “shortcut” to avoid a longer, more circuitous route on
surface sidewalks.
• Pedestrian only connections that are made beneath or over multiple roadway
bridge structures. These more resemble “catwalk” type bridges connected under or
over larger bridges. These occasionally occur where a pedestrian route crosses a
complex freeway interchange that includes multiple roadway bridges at different
levels.
• Pedestrian only bridge structures over water, canyons, railroad facilities,
and other obstacles.
• There are other possible combinations of roadways and pedestrian routes not
discussed.
The Board needs to clearly define the conditions where elevators and escalators
are needed. Consideration must be given to the purpose of the pedestrian route
and a variety of other factors. Clearly, the pedestrian bridges in Las Vegas
that carry thousands of daily pedestrian trips that avoid conflict with traffic
volumes exceeding 50,000 cars per day should have both escalators and elevators.
However, pedestrian stairways between streets in steep terrain, that carry less
that 25 pedestrian trips per day, should not warrant the need for an elevator.
1105.5.3 Approach. Where the approach exceeds 1:20, the approach shall be a ramp
48 inches (1220 mm) minimum in width and shall comply with 405. Where the rise
of a ramped approach exceeds 60 inches (1525 mm), an elevator complying with
407, or a limited- use/limited-application elevator complying with 408 shall be
provided.
PDOT COMMENT: This is a very broadly written requirement that requires the
installation of elevators if the ramps at overpasses or underpasses exceed 60
inch vertical change. Section 405 of the proposed ADAAG addresses ramp
specifications along accessible routes. It does not appear to have an automatic
requirement for installation of an elevator. 405 only limits a single ramp rise
to 30 inches. There are no limits to the number of successive ramps that may be
used in an accessible route. However, within buildings, because of limited
space, designers select the use of elevators or escalators to conserve the space
that would be consumed by successive ramps.
It appears that the Access Board is setting a requirement for the public
right-of-way that does not exist for buildings. Elevators are being required in
the outdoor environment when they are NOT REQUIRED in the indoor environment.
Elevators in buildings are the obvious mode of choice because they are build in
a space that is typically secure and environmentally controlled. Elevators are
the most cost efficient means to move persons between different levels. The
benefit of an elevator in an interior space typically outweighs the cost of
construction and maintenance. However, this is not the case for elevators in an
outdoor environment.
Elevators in the public right-of-way are subject to multiple adverse conditions.
These adverse conditions can easily affect the working parts of this type of
machine and cause them to fail. Excessive heat or cold can damage or destroy
hydraulic systems. Precipitation, in the form of rain, ice, or snow can stop
moving parts with rust or ice seizure. Dust and debris in the outdoor
environment can also stop moving parts from moving. Exterior elevators cannot
always be secured and are subject to damage by vandalism, which in turn causes
failures.
Interior elevators simple attach to the interior structure of the building.
Exterior elevators are considerably more expensive because they need their own
exterior structural support system.
We request that the Board reconsider this proposed requirement. The public
right-of-way is not a square or rectangular space that is confined by exterior
building walls. It is a longitudinal or linear space that affords public
agencies the ability to make accessible connections using sidewalks and ramps.
Public works agencies should be given the option to choose different options
that provide accessible connections. Ramps and sidewalks could be used where
space is available. Elevators and escalators could be used where space is
severely constrained.
1105.6 Roundabouts. Where pedestrian crosswalks and pedestrian facilities are
provided at roundabouts, they shall comply with 1105.6.
1105.6.1 Separation. Continuous barriers shall be provided along the street side
of the sidewalk where pedestrian crossing is prohibited. Where railings are
used, they shall have a bottom rail 15 inches (380 mm) maximum above the
pedestrian access route.
PDOT COMMENTS: Continuous barriers need to be defined here or in section 1101.3
Defined Terms. Continuous barriers should include, and not be limited to:
landscape buffers that do not contain a walkable surface as defined by 302.1,
fences, pedestrian railings, and vehicular guardrails.
No guidance is provided regarding the boundary for where a roundabout
intersection begins or ends and thus a barrier begins or ends. The nature of a
roundabout intersection is similar to a curved section of roadway or a mid-block
crossing. The requirement of a street-side barrier at a roundabout intersection
to separate vision impaired pedestrians from the roadway seems arbitrary. The
logical extension of such need for barrier would be to install barriers at the
edge of every sidewalk which is adjacent to a street. No substantive argument or
evidence has been provided that distinguishes a modern roundabout pedestrian
crossing as inherently less safe than any other mid-block crossing design or
intersection treatment, and thus warranting such barrier. Location of the
pedestrian crossing can be accomplished with a depressed landing adjacent to the
ramp that directs pedestrians into the marked crossing.
1105.6.2 Signals. A pedestrian activated traffic signal complying with 1106
shall be provided for each segment of the crosswalk, including the splitter
island. Signals shall clearly identify which crosswalk segment the signal
serves.
PDOT COMMENT: The guideline appears to apply to all sizes and types of
roundabouts with pedestrian facilities regardless of the level of auto or
pedestrian traffic use. As roundabouts have so many different applications, with
a similar variety of pedestrian environments, a single protocol without regard
to traffic volume or the number of entry or exit lanes a pedestrian is expected
to cross will unduly limit the modern roundabout's application due to the cost
of this guideline. This would be unfortunate as modern roundabouts have a clear
record of reducing total crashes and crash severity as compared to standard
signalized traffic control. We suggest that the Board conduct additional
research into the methods used in Australia and Europe, where modern roundabouts
are used at high pedestrian use locations with regular frequency.
The guideline singles out the modern roundabout intersection control geometry
without a clear argument or evidence of a safety need. The logical extension of
this guideline is the need for pedestrian actuated signals at all intersections,
regardless of traffic volume.
Signalizing each approach to a roundabout could also have several negative
consequences including increased congestion, queues extending into the
roundabout, rear-end accidents, and increased costs. Adding signals to each
approach of a roundabout could easily add over $150,000 to the cost of the
roundabout installation, not counting added annual maintenance and operation
costs.
1105.7 Turn Lanes at Intersections. Where pedestrian crosswalks are provided at
right or left turn slip lanes, a pedestrian activated traffic signal complying
with 1106 shall be provided for each segment of the pedestrian crosswalk,
including at the channelizing island.
PDOT COMMENTS: The correct term for “slip lanes”, as used by the AASHTO Policy
on Geometric Design of Highways and Streets [ the Green Book ], is auxiliary
lanes.
For right turn auxiliary lanes, traffic is not always controlled with signals.
Below are some of the methods currently used in this application:
• Signal control of through traffic lanes and signal control of the auxiliary
right turn lane.
• Signal control of the through lanes and “yield” control of the turn lane.
• Signal control of the through lanes and “stop” control of the turn lane.
• Stop control of the through lanes and “yield” control of the turn lane.
• No control of the through lanes and no control of the turn lane.
• Other combinations are possible.
The proposed regulation requires a pedestrian traffic signal for all situations
without considering the variety of variables involved. The Board needs to study
this further before setting a requirement that one solution fits all
applications.
1106 Accessible Pedestrian Signal Systems
1106.1 General. Pedestrian signal systems shall comply with 1106.
1106.2 Pedestrian Signal Devices. Each crosswalk with pedestrian signal
indication shall have a signal device which includes audible and vibrotactile
indications of the WALK interval. Where a pedestrian pushbutton is provided, it
shall be integrated into the signal device and shall comply with 1106.3.
PDOT COMMENTS: We do not believe that every signalized crosswalk with pedestrian
signals needs to have accessible signals as well. In downtown Portland we have
numerous small, yet closely spaced signalized intersections. Many of the
crossing distances are less than 30 feet across one-way streets while the
signalized intersections are slightly more than 200 feet apart. These simple
two-phased intersections are easily crossed by people with visual impairments.
If we were to add accessible signals to all of these downtown intersections, the
added noise could actually cause confusion for blind pedestrians. Even the best
accessible pedestrian signal devices available today have trouble properly
adjusting noise output for changing conditions (sudden loud or quiet noise
levels, changes in atmospheric conditions, etc). Hard surfaces in the downtown
would reflect the audible signals and these signals would often be clearly heard
at adjacent intersections, potentially misleading blind pedestrians on when to
cross.
That said, we also agree that many of our signalized intersections do need
accessible signals. We just ask that the Board add language to allow exceptions
where accessible signals would not be required. Wording for this exception could
read something like the following: “An accessible signal may not be required if
an engineering study shows that visually impaired pedestrians using skills
taught by orientation and mobility specialists can easily use the crosswalk in
question. Factors for not needing an accessible signal may include short
crossing distances, simple signal phasing, other clear audible queues, and
simple intersection geometrics. The engineering study must provide compelling
reasons for not installing an accessible pedestrian signal.”
1106.4 Directional Information and Signs. Pedestrian signal devices shall
provide tactile and visual signs on the face of the device or its housing or
mounting indicating crosswalk direction and the name of the street containing
the crosswalk served by the pedestrian signal.
1106.4.2 Street Name. Signs shall include street name information aligned
parallel to the crosswalk direction and complying with 703.2.
PDOT COMMENT: We strongly object to this requirement in that it is inconsistent
with other requirements. Street name signs are not required at any other type of
intersection. Use of a traffic signal at certain intersections to give traffic
flow specific timed intervals of having the right-of-way is still only a form of
traffic control. Stop controlled or yield controlled intersections are not much
different, yet tactile signs for pedestrians are not required. If the Board
wants to provide guidance information for blind travelers, then all
intersections should have tactile signs that identify the street names.
1107 Street Furniture
1108 Detectable Warning Surfaces
PDOT COMMENTS: After spending $20,000 to test products, make over 100
installations, and conduct opinion surveys with more than 40 blind persons, we
are not convinced that requiring detectable warnings at all curb ramps is good
public policy.
Our findings indicate that blind persons could not depend upon the detectable
warnings even if every ramp included them. Blind travelers use so many other
cues to travel that detectable warning would only provide minor benefit. Most of
the persons that we worked with were reasonably well trained and travel quite
well without detectable warnings. The opinions of our blind public pertaining to
detectable warnings are not any different than the comments received by the
Board in response to the proposed draft guidelines. Many liked them, many did
not.
From a cost perspective, installation of detectable warnings will be a very
expensive endeavor. We found that it would cost between $25 - $30 per square
foot of detectable warning surface. A single ramp installation would be at least
$200. A typical intersection with 8 individual ramps will cost $1,600. Portland
alone has 15,000 intersections. Over time we will spend $24 million (in
equivalent 2002 dollars) to complete all of the detectable warning installations
in Portland. The national investment in this effort will certainly exceed $10
Billion.
Based upon the input of our blind citizens, we support the discretionary
application of detectable warnings only at certain locations. These locations
include:
• On perpendicular curb ramps that have grades (slopes) flatter that 5%
• In advance of all active railroad tracks that cross the pedestrian access
route of a sidewalk area
• At all other areas where the pedestrian sidewalk area is not clearly
delineated from the roadway by curbs or other channelizing barriers.
We also found that detectable warnings were almost useless on all diagonal curb
ramps and most ramps that were not aligned directly in-line with the direction
of travel. Our blind traveling public seldom strayed off-course to even find
diagonal curb ramps. Other types of ramps with radial alignments were easily
found by long cane users as they detecting a curb on the flare of the ramp. None
of our blind travelers wanted to waste their time searching for the detectable
warning surface in these locations.
The Access Board needs to give greater consideration to this issue. It is very
clear that some locations should have detectable warning. Most other locations
do not need them. Portland would rather utilize members of our blind community
to evaluate all questionable locations and would follow their guidance on
whether detectable warnings should be installed or not. We feel that this would
be a better alternative that having the nation needlessly spend billions of
dollars for detectable warnings that provide no benefit to the users.
1108.2 Location.
1108.2.1 Curb Ramps and Blended Transitions. The detectable warning surface
shall be located so that the edge nearest the curb line is 6 inches (150 mm)
minimum and 8 inches (205 mm) maximum from the curb line.
PDOT COMMENT: Alignment of the detectable warnings is not discussed. Detectable
warnings need have the square grid pattern aligned with the direction of travel.
On ramps that intersect the street surface on a radius, the detectable warning
surface should also be correctly aligned for pedestrian travel but should not be
required to exactly follow the radius of corner. Companies manufacture
detectable warning products to meet the square grid pattern. These products
cannot be installed to meet a horizontal curved area. An exception needs to be
noted and a graphic provided.
1109 On-Street Parking
1110 Call Boxes
1111 Alternate Circulation Path
1111.1 General. Alternate circulation paths shall comply with 1111.
1111.2 Width. The alternate circulation path shall have a width of 36 inches
(915 mm) minimum.
1111.3 Location. The alternate circulation path shall parallel the disrupted
pedestrian access route, on the same side of the street.
PDOT COMMENTS: It is very shortsighted for the Access Board to decide that one
alternative circulation path on the same side of the street will fit all
situations. There are a variety of work zones in pedestrian areas that we
encounter daily. Most could not accommodate a same side of street alternate
circulation path. Sidewalk work zone examples include, but are not limited to:
1. Complete demolition and full reconstruction of roadways including the removal
of all existing vehicular travel lanes, bike paths, furnishing zones, and
sidewalks. All travelers are detoured to parallel alternate streets.
2. Similar to #1 above, but only half of the street width is being demolished
and reconstructed at one time. All travelers are detoured to the opposite side
of the street or to parallel streets.
3. Utility connections from the street to a building. This work zone crosses
vehicle travel lanes, bike lane, furnishing zone, and sidewalk. The safety of
all public users prevents access to the work zone. Users are shifted to the
opposite side of the street.
4. Intersection closures for street paving. All users are detoured to parallel
open streets.
5. Installation of curb ramps or new sidewalk facilities the prevent the public
from using these facilities until the concrete has sufficiently cured.
6. New building construction which utilizes the full sidewalk width and portions
of the street area. Pedestrians and vehicles are either moved to the opposite
side of the street or detoured to parallel open streets.
We suggest that this condition be amended to read: "1111.3 Location. An
alternate circulation path shall be provided to the disrupted pedestrian access
route, on the same side of the street, on the opposite side of the street, or on
a parallel street with a marked detour route.