Brant Williams, P.E.
|October 28, 2002|
Comments of the Draft Guidelines
Portland Office of Transportation
Brant Williams, P.E.
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.
122.214.171.124 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.
1126.96.36.199 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.
1108.2.1 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.
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