David C. Dryer, P.E. and Larry D. Nelson, P.E.
October 24, 2002


Re: Comments of the Draft Guidelines on Accessible Public Right of Way

Thank you for the opportunity to comment on the Draft Guidelines on Accessible Public Right of Way. The comments below are from the Engineering and Traffic Engineering Divisions of the City of Madison, Wisconsin. These two Divisions are responsible for the majority of the design and maintenance within public right of way.

The City of Madison Engineering and Traffic Engineering Divisions support the AASHTO review comments on the Draft Guidelines on Accessible Public Right of Way and have the following additional comments.

Section 1102.3 Alternate Circulation Path

This requires that an alternate circulation path complying with 1111 shall be provided whenever an existing pedestrian path is blocked. Section 1111 states that the path shall be parallel to the disrupted path and on the same side of the street. While it is desirable to provide this protected route, it is often not feasible where large-scale building and public works projects physically preclude the same side path. The City has an aggressive program of replacing sidewalk and we feel this requirement is impossible. Within the public right of way and adjacent to the street, we typically have a grass and tree space between the curb and the sidewalk and a 5-foot sidewalk. In most instances there is not space to provide this; and where space was available, the construction of a parallel route would be costly and expose the users to danger. It would be reasonable to require that the alternate path be provided if it could be provided on the opposite side of the street.

Section 1103.5 Grade

The exception needs to be expanded to cover streets that have a grade steeper than 1V:20H. Unless the sidewalk can exceed this grade it is impossible to lower the sidewalk to allow for construction a ramp and landing area to meet the guidelines.

Section 1103.8 Changes in Level

We understand that the sidewalk would be required to be beveled between ¼ inch and ½ inch. It will be infeasible to repair all sidewalks over ¼ inch offset. The City of Madison has a plan to repair all sidewalks in the City over a 10-year period. We spend $1,500,000 every year to repair essentially one tenth of all sidewalk areas in a city of 200,000 people and we use a ¾ inch offset criteria. The financial implications of the ¼ inch criteria are significant. Furthermore, displacement of sidewalks which occur during normal winter freezing of the subsoil often exceeds ¼ inch. In summary based upon our considerable experience, we are confident that the public will not accept a program to replace sidewalk with offsets less than ¾ inch.

Section 1104.2.1 Perpendicular Curb Ramps.

The requirement is not practical because the radius provided for the curb at the intersection is in the ramp area.

Section 1104.2.1.1 Running Slope

The minimum running slope of 1:48 for a perpendicular ramp seems unnecessary constraint. In areas with varying terrace width it is common to have one ramp of a perpendicular pair to be at a grade of 1:12 and the other ramp to be anywhere from near flat (just providing drainage), to back- pitched to match existing surroundings.

Section 1104.2.2.1 Running Slope

The minimum running slope of 1:48 for a parallel seems unnecessary constraint. In areas where the grade of the street is at a minimum (1:200) to provide drainage the parallel ramp would have a steeper slope than the surrounding street and sidewalk and provide for an awkward transition.

Section 1104.3.2 Detectable Warnings

We urge the access board not to adopt this standard at this time. The City of Madison and the Wisconsin Department of Transportation worked extensively on the issue of detectable warnings in the mid-1970’s. We worked with the Blind Council of Wisconsin, Wisconsin Schools for the Blind, and the Governor’s Committee for People with Disabilities to develop a statewide standard. The result was diamond pattern texturing, which is merely stamped or rolled into fresh concrete. The standard was accepted by all groups and was adopted by State Statute. The surface is not slippery, snow is easily removed with shovels or snow plows and the surface maintains its texturing and contrast for as long as the concrete lasts. The Blind Council or the City of Madison is not aware of any complaints with texturing.

We have revisited our design and are in the process of improving the design to accommodate as much of the suggested guidelines as possible. The main issue with curb ramping in Wisconsin is diagonal ramps. Over the years the visually impaired have come to rely on curb ramps as a cue for orientation to the street crosswalk. The Blind Council would in fact prefer to teach and train individuals to understand that the “right side of the ramp represents the right side of the crosswalk”.

Work will continue through the winter months testing and evaluating various Detectable Warning Devices from manufacturers around the nation. Several prototypes have been installed and will be evaluated for effectiveness as a warning, safety and durability.

Initial application and testing of truncated domes has raised several concerns with us. In the short time that we have been testing truncated domes, we have received one report of a person who lost balance when traveling over the domes and ending up not being able to regain control until she was in the middle of traffic, three reports of slipperiness, one report of a person refusing to have the domes in front of his property and several comments that one of the products could be a potential trip hazard. Pedestrian safety on ramps for all users is of the utmost concern. We have not had an opportunity to test the various products through a winter season and we have concerns about shoveling snow and the accumulation of ice on some products.

We would appreciate an opportunity to experiment further with detectable warnings and to have more input into the standard.

Section 1104.3.4 Grade Breaks

On occasion it is necessary to place a grade break in a ramp to prevent water from entering the ramp from the street. This is more common in areas requiring back-pitched ramps to meet existing conditions.

Section 1104.3.5 Changes in Level

The requirement that no changes in level occur in curb ramps or blended transitions is more restrictive than in other part of the pedestrian access corridor. As stated earlier it will be infeasible to repair all offsets of ¼” let alone less than ¼”

Section 1105.2 Crosswalk Width

This provision requires that the parallel lines delineating a marked crosswalk be 96 inches in width versus the current standard of 72 inches. The City sees no improvement gained with this requirement versus the current standard. It will only have the effect of increasing material costs associated with the installation of a special zebra crosswalk by 33 percent and will further reduce the City’s ability to use these special type crosswalks. The City recommends that wider crosswalks be installed based on documented need than a blanket requirement.

Section 1105.2.2 Pedestrian Crosswalk Cross Slope

The provision requires that streets in excess of 2% be flattened to 2% at intersections. AASHTO standards would apply to the vertical geometry used on the roadway as the change in grade was made. The standard would specify the length of vertical curve required to transition from the roadway profile slope midblock to the 2% slope required at the intersection. If you assume an 8% grade, a 25 MPH posted speed/30 MPH design speed and design criteria for stopping sight distance, the requirement would result in 17 feet of extra cut or fill. Slopes steeper than 8% or posted speed limits in excess of 25 MPH would have a much greater impact. This criteria would have a major effect on the price of new development and consequently the price of housing.

We have not found a practical way to provide 2% cross slopes for ramps when the street grade exceeds 5% for type 2 ramps and 7% for type 1 ramps. Please provide us with design standards that are economically feasible to apply and guidelines that are achievable. Two things that can affect the cross slope of ramps, in addition to the street grades, are the curb radius and the location of the ramp. Smaller curb radii require that the change in elevation take place over a shorter distance and result in a steeper ramp cross slope. Ramps that are located near mid-curve (type 1 ramps) have a section of curb on either side which can be installed at a grade, which is slightly steeper than the street grade, to allow the ramps to have a cross slope which is closer to 2%. Ramps located near the curb point of curvature (type 2 ramps) must have a cross slope which is very close to the street grade.

Section 1105.3 Pedestrian Signal Phase Timing

The requirement to reduce the pedestrian walking speed to 3 fps will have detrimental impacts that must be considered. Currently the City will adjust pedestrian signal timing based on special needs users. To require a blanket change can be expected to result in needless congestion and its associated impacts.

Section 1105.5 Pedestrian Overpasses and Underpasses

The City of Madison has attempted to stay under the 1:20 slope on recent overpass projects. This may not always be possible, however; and we may need to go to the 1:12 criteria with landings every 30 feet. The elevator criteria are impractical. Requiring elevators will result in high initial costs, high ongoing maintenance costs, and problems with security and vandalism. It is extremely unlikely that the City of Madison would build an elevator for a pedestrian overpass. This may have the effect of eliminating overpass projects.

Section 1105.6 Roundabouts

The proposed guidelines require the installation of traffic signals at all legs of a roundabout. The City of Madison has been utilizing roundabouts and neighborhood scale traffic circles since 1997. The requirement that signals be installed at these locations will prove problematic. Certainly it is desirable to consider the impacts these devices have on the pedestrian environment, and it is noted that the Access Board is interested in beginning discussion on how to address this. We believe the blanket signalization requirement is premature given the limited data to date as well as the interest FHWA has expressed in both studying and identifying potential solutions to this problem. We believe this review should be allowed to occur before ADA requirements preclude alternatives.

Clarification also needs to be made between roundabouts and neighborhood traffic circles used as traffic-calming features. Certainly it cannot be the Board’s desire that low-volume neighborhood traffic circles be signalized. This requirement is unnecessary at these low volume locations. Simply stated circles will cease being considered both due to the resulting increased cost and more importantly lack of residents support. It is expected that Madison residents will find this requirement unacceptable.

Madison has also implemented, on a more limited scale, the use of modern roundabouts. The City has installed several as part of new residential Neighborhoods, and is considering the potential of roundabouts at some arterial street intersections. Without doubt roundabouts can significantly improve safety and reduce delay with its ancillary negative impacts.

Requirements to signalize roundabout will reduce these benefits. Pedestrian-actuated signals will rest in Green on the entering/exiting legs of the roundabout. The City’s experience with these types of signals is that motorists accustomed to the area quickly tune them out, and when actuated motorist compliance was resultantly poor. Drivers are also attuned to the presence of signals at intersections located at the entrance to an intersection. Signals placed on the exiting leg are atypical, unexpected and will likely be confusing, in addition the necessary queuing space for exiting vehicles is not present. This may worsen rather than improve safety.

Simply stated the City is concerned that the signal requirement will result in the removal of roundabouts from consideration for future projects.

Rather than require that modern roundabouts be signalized, the City would recommend that an alternative slate of improvements be considered and reviewed including signing, markings, pedestrian and motorist education and the enforcement of the pedestrian right of way laws.
Section 1105.7 Turn Lanes at Intersections
The proposed guidelines require the use of signals at left- or right-turn lane locations where pedestrian crosswalks are provided. It is unclear whether this requirement applies to only existing signalized locations with slip lanes or at all slip lanes regardless of signalization. It is difficult to comment on this requirement without having an idea of the Board’s definition of slip lanes.

If applied to slip lanes at unsignalized intersections, this requirement will result in numerous unwarranted signals and their resulting negative effects. This requirement can be expected to worsen not improve pedestrian and motorist safety.

The geometric design of some exclusive slip lanes is such that signalizing them will be difficult, similar to those problems previously identified for roundabouts. The City’s experience with these types of signals is that motorists accustomed to the area quickly tune them out, and when the signal is actuated motorist compliance is resultantly poor. Signalizing turn lanes when unnecessary will also have significant operational impacts of lowering capacity and increasing congestion.
The City recognizes the need to provide pedestrian crossings of exclusive turn lanes and has used a modified turn lane design where appropriate to result in lower vehicle speeds. The City recommends rather than a blanket requirement that all turn lanes be signalized that consideration be given to other improvements, including signing, markings, pedestrian and motorist education, and the enforcement of the pedestrian right of way laws.

Section 1106 Accessible Pedestrian Signals (APS)

This guideline requires that all pedestrian signals be accessible and requires each signal with pedestrian indicators be configured with an APS. This will be a significant cost item for the City.

The City has implemented various types of intersection audio signaling equipment to assist persons with visual impairments. In certain instances, this has improved conditions; in some locations, it has also resulted in noise complaints from nearby residents. It is recognized that the Board believes that new technology will address this problem using ambient noise adjustments, but it is unlikely that this equipment will work as well as believed. The added complexity of APS at all signal locations will increase installation costs and will greatly complicate maintenance and increase maintenance costs.

The City supports the desire to make signalized intersections accessible. However, rather than a blanket requirement that all signalized locations be configured with APS that local units of government implement APS as needed, working in conjunction with the visually impaired community.

Section 1109 On Street Parking Spaces

This guideline requires that an accessible parking stall with five-foot wide curb cutout be required on each block face. It is unclear whether this requirement applies to all block faces or only to metered spaces or marked spaces located in commercial business districts. Clearly if this pertains to residential districts, there will be significant costs associated with signing and delineating such parking. It is unlikely the community would view a residential requirement as reasonable.

As it pertains to metered or commercial spaces, there are additional concerns associated with the access aisle requirement, including cost associated with construction and associated storm sewer work, as well as snow removal difficulties. The City recommends that it be allowed to continue its current practice of locating accessible parking stalls at the block end.

Section 1109.7.3 Parking Meter Displays and Information

It is unclear if this guideline requires that all parking meter displays be visible from a point located 40 inches maximum above the clear floor area. The City questions whether it is the Board’s intent to require all meters be held to the 40-inch maximum height or only to those meters at accessible parking spaces.

In the State of Wisconsin, persons with disabilities are not required to pay at on-street parking meters; therefore, in Wisconsin the 40-inch height requirement is immaterial as it pertains to accessible parking spaces. However, if the 40-inch height requirement is to apply to all meters, this will be an excessive requirement. It will create operational and maintenance difficulties where storage of snow in a narrow windrow surrounds the meter pole. While the meter is accessible, lowering the display can be expected to place the meter vault into the snow bank. This is unworkable in our northern climate.

Sincerely, Sincerely,

David C. Dryer, P.E.
City Traffic Engineer

Larry D. Nelson, P.E.
City Engineer


 

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