Lewis H. Garrison, P.E. 
October 1, 2002

SUBJECT: DRAFT GUIDELINES FOR ACCESSIBLE PUBLIC RIGHTS OF WAY


Dear Mr. Windley:

We are providing the following comments for consideration in preparation of the final rules for the Guidelines for Accessible Public Rights of Way.

1) Section 1102.2.2 Alterations

This section deals with alterations, specifying that when “technically infeasible,” alterations shall comply with these guidelines to the maximum extent possible.

The term “technically infeasible” can have a broad or narrow interpretation, and more guidance is needed in the definition of these terms.

2) Section 1102.14 On Street Parking and Section 1109 On Street Parking

This section requires one disabled space per block face designed with all the amenities of a standard disabled space with, in the case of a parallel space, an access aisle of 60 inches the full length of the space (Section 1109.2). The only exception is where there is less than 14 feet of right of way behind the curbline. For angled spaces an access aisle of 96 inches is required (Section 1109.3).

In our downtown area, in which parking is a premium, this would, on blocks with diagonal parking, eliminate one space per block to accommodate the aisle. In the case of parallel parking, the reduction in sidewalk width would be significant, not only for providing the access aisle of 5 feet but additionally the necessary area to provide an access ramp with permissible grades.

In the case of parallel parking in our downtown area, we have only enough block length for about 12 spaces. With the proposed regulations, the resulting ratio of disabled spaces would be 1:12 far in excess of the standard required on private lots of 1:25.

3) Section 1104.3.7 Clear Space

This section requires a 48 inch by 48 inch clear space within all crosswalks wholly outside the vehicle travel lane.

If I interpret this correctly, this space will require an additional 4 foot paved width on each side of the street. Probably not a problem if the crosswalk is in the radius of the intersection, but if on the tangent, the extra street width will be required at that point increasing the length. Since the ramp provides somewhat level access to the street, why is this extra 4 feet necessary?

4) Section 1105.2 Crosswalks

The cross slope of all marked crosswalks shall not exceed 1:48 maximum measured perpendicular to the path of pedestrian travel.

This requirement will mandate “tabled” intersections, similar to those in San Francisco. Although this would be a great traffic calming device, the rideability of major arterial and collector streets would greatly suffer, resulting in lower speeds, or accidents, especially considering that some of these intersections could be commingled with streets not built to these standards. This section is not well thought out.

5) Section 1105.3 Pedestrian Signal Phase Timing

The requirement to time pedestrian crossings at 3 feet per second will create unneeded delay for the entire street system. A more reasonable approach is to consider the individual needs of the disabled at specific locations rather than for the entire signal system.

6) Section 1105.5 Pedestrian Overpasses and Underpasses

This section requires an elevator for any pedestrian overpass or underpass with a rise greater in the ramp approach than 60 inches.

This will greatly increase the project cost and seems quite excessive and could be accommodated by level resting places in the ramps as per the current ADA guidelines.

7) Section 1105.6 Roundabouts


This section deals with roundabouts. It requires an actuated pedestrian signal for crossing each approach of the roundabout. In addition, pedestrian actuated signals will be required at all splitter islands, i.e., right turn slip lanes or lanes turning between an island and the edge of the roadway, curbline or otherwise.

The provision of signals at a roundabout defeats the entire purpose of the facility which is to increase capacity and reduce delay experienced at a signalized or all way stop intersection. If this section is adopted, there will be far fewer of these built.

Signals at slip lanes for signalized intersections provide a measure of safety. However, as the guideline is written, it appears to apply to all intersections and driveways regardless of signalization. If this is the case, the guideline will eliminate this feature of design or require the signalization of the entire intersection or driveway. This guideline should only apply to signalized intersections.

8) Section 1111 Alternative Circulation Path

Requiring a pedestrian path through a construction site on the same side of the street is not practical nor reasonable, either for the able bodied or the disabled. Most street construction projects require use of the entire area both for the construction itself and for the equipment. Placing the pedestrians outside of this area and on the same side of the construction locates them either on private property or in the middle of the street. Private property requires easements and is not always open. Placing them in the street, which also requires breaks for contractor access, places the pedestrian in a precarious and hazardous location. Rerouting them to the other side of the street eliminates these concerns and is far safer.

Sincerely,

Lewis H. Garrison, P.E.
City Traffic Engineer
 

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