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
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
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 1220.127.116.11 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
Section 118.104.22.168 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
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
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
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
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
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
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
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.
David C. Dryer, P.E.
City Traffic Engineer
Larry D. Nelson, P.E.