|October 28, 2002|
Re.: Proposed ADA Guidelines Pubic Right of Way
We are appreciative of the Access Board’s work in establishing guidelines and standards for ADA compliance in public rights of way. Such guidelines are sorely needed. Even within our County there is inconsistency among the various jurisdictions in the construction of ADA features.
It is our County’s firm commitment to provide for accessible pedestrian routes to the maximum extent practicable within our rights of way. However, we have a number of other goals and regulations that must be satisfied. This requires that consideration be given to these other objectives in formulating specific standards and guidelines for a particular issue, such as ADA. Most of our goals and regulation compliance requirements are the same ones that most public agencies in this country face. They include compliance with Federal Clean Water Act requirements, recognized road/street geometrics standards, recognized traffic engineering principles, local and state ordinances, and political mandates to minimize environmental impacts, to name a few. Implementing these ADA guidelines, as written, will conflict with one or more of these.
We know it is not the intent of the Access Board to force local agencies to comply with the ADA guidelines regardless of the implications with other objectives. A thorough examination of the adverse affects the proposed ADA guideline may have on public agencies ability to comply with other mandates must occur before adoption of a final set of ADA guidelines.
Having that been said, we offer the following discussion regarding specific proposed guidelines that do give us cause for concern.
Section 1102.2.2 Alterations. Requires that where existing elements or spaces in the public right-of-way are altered, the altered element or space shall comply with the applicable provisions of Chapter 11.
Section 1102.2.2 also allows exception to this requirement where “technically infeasible” and requires compliance to the “maximum extent possible”. Both of these terms are not defined. Unless properly defined, the term “maximum extent possible” will render the exception clause moot.
In the discussion of the draft guidelines, the Board seems to imply that existing construction, right-of-way wideth and underground structures are factors to determine whether it would be technically feasible to comply with Chapter 11. Carrying to the extreme, the term “maximum extent possible” will nullify all these considerations.
As an example, the narrow inaccessible sidewalks on both sides of a narrow street in an older central business district are in need of repair. The street pavement is only 20 feet wide with one traffic lane in each direction. The local jurisdiction decides that compliance with Chapter 11 is infeasible because space is limited and right of way width is not adequate. The opponent may argue that the decision does not meet the “maximum extent possible” test. The local jurisdiction could close the street to vehicular traffic and convert the entire street to pedestrian use or reduce the width of the street to one traffic lane and convert the street to a one-way street regardless of circulation and traffic congestion needs.
Suggested Revision: The guideline should add the following factors when determinig whether it is technically feasible to comply with Chapter 11: The provisions of the Federal Clean Air Act and the Federal Clean Water Act, safety, conflicts with transit services and the relative cost of compliance.
Section 1102.6 Curb Ramps and Blended Transitions– Requires that ramps connect to the street crossing within the width of the crosswalk.
Impact of Change: This eliminates the use of a single ramp placed in the middle of the curb return because it does not connect within the width of the crosswalk, marked or unmarked. Because of the guidelines’ discussion about ramp alignments and placing “perpendicular” ramps at right angles to the curbs, some earlier comments questioned whether the Access Board intended to allow ramps in the curb returns at all. They questioned this because placing ramps in the returns at right angles (radial) to the curb will result in ramps that are not parallel (aligned) with the route across the street. (Shouldn’t the ramps align with the direction of the crosswalk or provide tactile directions?)
Also, placing two standard ramps in our standard 20-foot radius curb returns will be very crowded and create a curb “spike” between the ramps, and curb transitions that extend beyond the curb returns.
If the Access Board’s intent is to eliminate ramps within the curb returns, there are serious safety issues involved with moving the pedestrian crossings back from the intersections. Drivers will typically not stop so far back from an intersection. They will encroach into the crosswalk area to allow them to look for cross traffic. Setting ramps back away from curb returns will increase the potential pedestrian-vehicle accidents.
Compliance Measures: Presuming the Board will allow ramps in the returns. We will need guidance from the Access Board concerning which criteria should we adhere to in designing these dual ramps, i.e. align ramps with street crossings or keep them on a radial with the return radius.
Suggested Revision: Allow single ramps on smaller radius returns (25’ max. radius) with tactile directional tiles to direct visually impaired pedestrians to each crossing especially on residential low-volume streets.
Sections 1102.14 On-street Parking and 1102.15 Passenger Loading Zones– Requires one accessible parking space per block face and one at every passenger loading zone in compliance with Section 1109.
Impact of Change: This broad brush approach to providing “accessible” parking can lead to an inordinate percentage of accessible parking places in all types of zoning whether it be commercial or residential. There are a number of comments posted on the Access Board’s website about this topic.
Referenced Section 1109 also requires that the curb be recessed 60 inches to provide for an “access aisle”. The length of this space because of the curb recess takes up at least the equivalent of two standard parking spaces, too. For commercial areas dedicating this many extra-length spaces will be detrimental to the overall number of parking spaces and it will limit an agency’s ability to add or move such access parking spaces on an as-needed basis.
In higher density residential subdivisions, a lot’s entire road frontage could be dedicated to one accessible parking space eliminating general parking in front of that house. There is rarely a parking problem in subdivisions, and the physical impacts of such features in residential areas make this mandate in residential areas unwarranted.
The need for an access aisle seems extraordinary and of little practicality. Very few disabled drivers who use a wheelchair and exit the vehicle from the driver’s side would benefit from this access aisle. Can’t disabled persons exiting the passenger side access directly onto the sidewalk area if the vehicle is pulled close to the curb?
Suggested Revision: The requirements should eliminate the 60-inch access aisle, and decrease the number of designated access spaces, both parallel and perpendicular, to the same percentages required in public parking lots. Residential areas should be exempt from designating accessible parking areas except on an as needed (as-requested) basis.
Section 1103.3 Pedestrian Access Route – The minimum width for the accessible path will increase to 48 inches (excluding curb widths) with no exceptions for a 36-inche minimum as allowed in public buildings ADA guidelines.
Impact of Change: If it were not for the need to place roadside signs in sidewalk areas next to the curb, and frontage improvement projects where utility poles occupy narrow rights of way, this would not be much of a problem.
However, our standard top of curb plus sidewalk width is 5 feet wide which is a standard with many agencies. Without an exception, we could not place a roadside sign in the sidewalk with the minimal 12-inch clearance from face of curb. We would be out of compliance by the width of the signpost. To increase concrete sidewalk widths 6 inches to provide the full 48-inch clearance nationwide it would represent a significant increase in the use of natural resources and increase the amount of impervious surfaces, contrary to Federal Clean Water objectives.
Most frontage improvement (curbs and/or sidewalks) projects in older neighborhoods in our County have only 7 feet of right of way behind the curb face. Within this 7-foot area, we must accommodate the utility poles and overhead wires while providing the specified clear width of sidewalk. We are able to adjust the poles near the curb with our standard 18-inch setback and fit 36 inches of sidewalk between the back face of pole and the existing right of way line to comply with the present ADA requirement. Moving a rigid object, such as a utility pole, closer to the curb face is not a viable solution for safety reasons. Therefore to comply with the new 48-inch requirement, we will have to go to the expense of acquiring rights of way at an extraordinary per square foot cost at each pole location. Even ignoring possible condemnation (eminent domain) costs, project costs will increase significantly and delay project delivery.
Suggested Revisions: Allow a 36-inch minimum clearance “exception” in compliance with ADAAG (accessible building guidelines) at isolated obstructions such as signposts and utility poles.
Section 1104.2.2 – The curb transition for middle block “parallel” ramps may be as long as 15 feet to minimize the steepness of the ramps on steeper grades.
Impact of Change: It will significantly increase the area needed for these types of ramps making them harder to place and decrease the amount of on-street parking.
Compliance Measures: Clarification on the use of longer curb transitions (transitions length versus road grade) to assure uniform compliance is also needed.
Suggested Revision: Change the maximum curb transition to 10 feet. Besides decreasing on-street parking, the 15-foot maximum transition length seems long and could be mistaken for a driveway.
Section 1104.3.7 Clear Space – Requires a 48”x48” clear space area at the foot of a curb ramp outside of the travel way.
Impact of Change: It is our understanding, that this requires a minimum 4-foot wide paved shoulder area at the foot of the ramp. It may eliminate the effectiveness of curb return bulb outs, used as a “traffic-calming” feature. The purpose of the curb bulb outs is to narrow the road to cause drivers to slow down, increasing pedestrian safety. This type of feature has become very popular in recent years. Maintaining the 48-inch clear zone will limit the bulb out “encroachment” and its visual affect on drivers.
Suggested Revision: Proposal 1): Allow an exception for all ramps that are aligned with the street crossing. (No turning actions are required by someone in a wheelchair at the foot of a ramp properly aligned so the clear area should not be necessary.)
Or, proposal 2): Allow an exemption for parallel ramps that are aligned with the street crossing. (Parallel ramps have a flat (2.08%)landing next to the curb, so there is no turning of the wheelchair because of the alignment and no steep slope immediately adjoining the curb to require one to hesitate in the roadway.)
Section 1105.2.2 Cross Slope and Section 1105.2.3 Running Slope– Crosswalks- These sections require crosswalks, whether marked or not, to have a maximum cross slope of 1:48 (2.08%) and a maximum running slope (grade) of 1:20 (5%).
Impact of Change: These directives will have a profound affect on the way we design roads. Road geometry and layout will be controlled by ADA requirements if these proposed guidelines become “law.”
These directives do clarify the long standing question that the maximum slopes for ramps and accessible paths are relative to horizon and not the grade of the road or walkway at intersections. Every intersection with pedestrian facilities regardless of its location will require that the grades of the streets be a maximum of 2.08% creating “table top” intersections in any terrain steeper than 2.08%. Road grades cannot be changed abruptly. Vertical curve transitions must be used. Vertical curve lengths are determined by the differences in grade and design speed.
So by flattening the intersections, the opposite effect occurs mid-block because of the over-steepening of mid-block grades due to the required vertical curves in accordance with good road geometric practice to make the roads drivable.
These “reversing” vertical curves will also greatly influence how close intersecting streets can be placed even in mildly sloping terrain and low design speeds.
Example1: Assuming a design speed of 35 mph (25 mph posted speed limit) and 800 feet between intersections and complying with AASHTO’s vertical curves for stopping sight distances on crest and sag vertical curves, the maximum average grade between intersections is 5.9% with the mid-block grade being 10.4%! (In the end we have flat “accessible” intersections but very steep mid-block grades that are less accessible).
Example 2: Using a design speed of 35mph and maintaining a maximum grade of 5% mid-block, I calculated the closest intersection spacing and average grade between intersections. The intersection spacing was controlled by the minimum vertical curve lengths of 105 feet since the algebraic grade difference was only 3% (3 x design speed in feet as recommended minimum vertical curve length per AASHTO). Therefore the intersection spacing was 266 feet and the average grade was only 3.2%. The greater the intersection spacing the closer the average grades would approach, but never equal, 5%.
These requirements present significant road/street geometric design problems and lend itself to agencies eliminating pedestrian facilities all together in mildly sloping to steep terrain, especially in subdivisions. Smaller residential developments may not be developed to the maximum allowed for the zoning because of the access limitation (intersection spacing) due to flattening the intersections.
It could also lead bigger developments into massive site grading to flatten the terrain so intersections can be closely spaced. Massive grading of hillsides invites a whole host of environmental, clean water and political issues.
Another “workaround” may be to force mid-block crossing by pedestrians since these crossings are exempt from the maximum cross slope of 2.08%. This is not good traffic engineering practice. These “workarounds” create significant economic, safety and environmental issues.
Suggested Revision: Business and commercial areas where the average slope between intersections is less than 5% should meet this criteria if the AASHTO conforming vertical curves do not steepen the mid-block grades over 5%. An exemption should be allowed for all residential areas and roads with design speeds that exceed 45 mph.
1105.3 Pedestrian Signal Phase Timing- Requires use of 3.0 feet per second walk speed for signal timing of the pedestrian phase and increases the crossing distance used to calculate the pedestrian phase.
Impact of Change: The additional time that must be allotted to the pedestrian phase will have a significant negative impact on the level of service for motorized traffic at busy intersections. In Contra Costa County this could put us out of compliance with level of service requirements mandated under a local transportation funding measure and State stature. On a typical four-lane road crossing with one protected left turn lane the crossing time will be increased from 18 seconds to 26 seconds. On a typical signal with two pedestrian phases, that would require an additional 16 seconds in the signal cycle length. To comply with local ordinances and state stature, many local jurisdictions in California prohibit pedestrian from crossing at key intersections. This requirement will further encourage this practice and will act against the objective of providing broad access to all. The inclusion of the ramp length in the calculation also seems very excessive, it will not happen very often that the signal will cycle immediately when the ped button is pushed. There should be time to move from the ped button to the curb line.
Compliance Measures: Every new or remodeled signal would have to be timed to a 3.0 feet per second (fps) walk speed for the pedestrian phase. During the project development stage using 3.0 fps in the modeling of the signal may require unusually long cycle lengths or additional lanes for vehicle capacity, which in turn would increase the walk time and hence the pedestrians exposure to traffic.
Suggested Revision: Allow local jurisdictions broader latitude to determine whether it is technically feasible to alter signal timing when a traffic signal is modified. We have no commenets on new constuction.
Section 1105.4.1 Length- This section requires median island refuges to be a minimum width of 6 feet in length along the pedestrians’ path of travel.
Impact of Change: This would require widening the typical existing 4-foot medians to 6-feet when improvements are made to the intersection. This additional two feet will add to right of way costs and require total modification of the intersection.
The impacts to safety if lanes are narrowed to accommodate the wider median must be considered especially for trucks making left turns from a narrower curb lane.
Suggested Revision: Do not institute this requirement for existing conditions unless ‘significant’ work is being done to the intersection (such as adding a lane). Otherwise this may hinder the installation of upgraded ramps at an intersection if this requirement is to be met with that level of improvement.
Section 1105.5 Pedestrian Overpasses and Underpasses – An elevator shall be provided for all pedestrian overpasses or underpasses that has a vertical rise of more than 60 inches.
Impact of Change: This will increase the cost of constructing and maintaining these facilities dramatically. These increased costs may render many safety related pedestrian overpass and underpass projects infeasible. In certain areas, these unsecured elevators present concern for vandalism, false alarms, etc.
Suggested Revisions: Eliminate this provision as long as a reasonable ramp access is provided.
Section 1105.6 Roundabouts- This section would require a pedestrian activated traffic signal at crosswalks associated with roundabouts.
Impact of Change: Not only do roundabouts typically require significant right of way acquisition and associated costs, the added cost of multiple pedestrian signals and barriers would likely cause roundabouts to be cost prohibitive. Adding pedestrian signals in some situations may make traffic levels of service unacceptable.
It is not understood what is meant by the requirement that “Signals shall clearly identify which crosswalk segment the signal serves.” Signal heads face the crosswalk which they serve, any signs added to the signal head would have to be legible to visually impaired users, this is not believed to be practical due to the distance at which these signs should be legible.
Suggested Revision: Require the use of high visibility crosswalks and appropriate signage at the pedestrian crossing locations at roundabouts as an option to pedestrian signals.
Section 1106.2.1 Location- Requires that pedestrian signal devices (ped push buttons) be located a minimum of 120 inches apart.
Impact of Change: In intersections with small radius curb returns it may be impractical or impossible to separate the signal devices by ten feet.
Suggested Revision: Require signal devices located less than ten feet apart to have ‘contrasting’ tones so users would be aware of the presence of two different signal devices. Each device would have to be clearly marked as required elsewhere in the proposed rulemaking.
Section 1106.3.2 Locator Tone: We would like clarification. Does the last sentence imply that if there is a malfunction in the pedestrian portion of the signal that the audio/vibratory feedback should also be disconnected? If so it is stating the obvious. If not, it is unclear what the intent.
Section 1111 Alternate Circulation Path - When sidewalks or roadside paths are temporarily blocked for construction or maintenance activities, an alternate path shall be provided on the same side of the road with barriers or barricades to separate the path from construction operations and/or other hazardous conditions with no exceptions.
Impact of Change: This requirement will be impractical in older urbanized areas with narroe streets. Standard procedures for construction activities have been to detour pedestrians to the other side of the road and require phasing of work to assure that one side of the road was open to pedestrians during construction. Presently, short-term maintenance activities typically make no accommodations for blocking sidewalks.
There are situations where it would be physically impossible to access the roadside construction and provide an alternate pedestrian route without closing a lane, detouring traffic, or acquiring temporary rights of way from adjoining property owners at great expense when this could be avoided by providing a safer route on the other side of the street.
Suggested Revision: Mandate an alternate accessible path for all construction operations that block pedestrian access in the same manner and along the same route as the temporary pedestrian access. Short-term maintenance that blocks the accessible route shall either comply with the requirements for construction operations or be performed in such a manner that impaired pedestrians can be safely escorted through the work area with minimal delay during the maintenance activities and the area is made “accessible” during non-work hours.
Finally, definitions are needed to clarify what constitutes a “public right of way,” for “barrier” as referred to in Section 122.214.171.124 “Diverging Sidewalks,” and “circulation path” as referred to in Section 1102.5.1 “Protrusion Limits”. Some agencies and developers may consider “private” streets as a way to avoid these ADA requirements. Would such streets if access is unrestricted be considered public rights of way?
Thank you for this opportunity to provide comments. If you need to contact me, please call (925) 313-2000.
Very truly yours,
Public Works Director
Contra Costa County Public Works Department
index previous comment next comment