From: Tarno Coleman, P.E.
Civil Engineering Associate
Marion County Department of Public Works


Marion County Department of Public Works strongly supports the comments and recommendations found in the document dated October 14, 2002 submitted by the American Association of State Highway and Transportation Officials. This document is attached as an appendix of our submittal. We have the following additional comments:

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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.

Background
The following definition is found in 3.5 Definitions of the ADA Accessibility Guidelines (ADAAG): "Technically Infeasible. Means, with respect to an alteration of a building or a facility, that it has little likelihood of being accomplished because existing structural conditions would require removing or altering a load-bearing member which is an essential part of the structural frame; or because other existing physical or site constraints prohibit modification or addition of elements, spaces, or features which are in full and strict compliance with the minimum requirements for new construction and which are necessary to provide accessibility."

While this definition is adequate for buildings, it does not address the issues arising from problems associated with natural terrain and topography.

Recommendations
Expand the definition. "Technically Infeasible. Means, with respect to an alteration of a transportation facility, that it has little likelihood of being accomplished because existing vertical and horizontal limitations would require violation of existing standards relating to vertical and horizontal alignment; or because other existing physical or site constraints prohibit modification or addition of elements, spaces, or features which are in full and strict compliance with the minimum requirements for new construction and which are necessary to provide accessibility."

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1102.2.2.2 Prohibited Reduction in Access. An alteration that decreases or has the effect of decreasing the accessibility of a public right-of-way or site arrival points to buildings or facilities adjacent to the altered portion of the public right-of-way, below the requirements for new construction at the time of the alteration is prohibited.

Background
The wording of this section may imply that adjacent buildings or facilities must be brought up to the requirements for new construction. An existing private access to a building may not be in compliance and should not be brought into compliance at public expense.

Recommendation
Reword the section for clarification. "1102.2.2.2 Prohibited Reduction in Access. An alteration that decreases or has the effect of decreasing the accessibility of a public right-of-way to or site arrival points for to buildings or facilities adjacent to the altered portion of the public right-of-way, below the requirements for new construction at the time of the alteration is prohibited.


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1111.3 Location. The alternate circulation path shall parallel the disrupted pedestrian access route, on the same side of the street.

Background
Requiring that an alternate circulation path is on the same side of the street creates logistical problems. Pedestrian routes are usually located between the right of way and the traffic lane. Construction access, or easements, is usually not available from the adjacent private property due to buildings, etc. This would require enough right of way space to move the pedestrian access to allow for 1) the new pedestrian access being constructed, 2) room to allow for required adjacent construction equipment access, 3) room to allow the temporary pedestrian access and 4) room for the displaced traffic travel lanes.

Recommendation
Reword the requirement to the following. 1111.3 Location. The alternate circulation path shall, where feasible as determined by an engineering study, parallel the disrupted pedestrian access route on the same side of the street.


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1105.2 Crosswalks. Crosswalks shall comply with 1105.2.

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1105.2.3 Running Slope. The running slope shall be 1:20 maximum measured parallel to the direction of pedestrian travel in the crosswalk.

Background
This requirement is reasonable at intersections where the natural terrain can accommodate this transition. An exception needs to be provided where the natural terrain is so steep that changes in vertical alignment cannot be accommodated using existing highway design and construction standards.

Recommendation
Reword the requirement to the following.
1105.2.3 Running Slope. The running slope shall be 1:20 maximum measured parallel to the direction of pedestrian travel in the crosswalk.

EXCEPTION: The grade of the pedestrian access route within a crosswalk shall not exceed the grade established for the adjacent roadway.




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.

Background
Reading this section is confusing. Is the purpose to specify the length of cut-through medians and pedestrian refuge islands or to require all un-signalized pedestrian crossings to be provided with refuge islands? In areas with many un-signalized intersections, this would require an additional obstruction placed in the roadway with corresponding changes in horizontal alignment.

Recommendation
Delete the reference to un-signalized intersections. 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, where provided, shall be 72 inches (1830 mm) minimum in length in the direction of pedestrian travel.


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1105.5 Pedestrian Overpasses and Underpasses. Pedestrian overpasses and underpasses shall comply with 1105.5.

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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.

Background
A pedestrian overpass is not defined. A highway grade separation structure with sidewalks could be considered a pedestrian overpass or underpass. These structures typically exceed a 60-inch ramped approach. Placing elevators in these circumstances would be extremely costly and unlikely to occur in most cases.

Recommendation
Change the section as follows. 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.

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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.

Background
Many intersections are un-signalized. A motorist approaching such an intersection does not expect a signalized stop on an otherwise uncontrolled intersection.

Recommendation
Marion County concurs with AASHTO's recommendation of "reserving" Section 1105.7, "Turn Lanes at Intersections," until further research can be conducted.

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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.

Background
There seems to be a lack of consensus among persons with visual disabilities as to the best method to accommodate their needs. These signal features require additional initial expense and maintenance. It would be very costly to retrofit existing signals. Experiments in various urban areas have met with much resistance from the disabled community.

Recommendation
Marion County recommends "reserving" Section 1106.2 "Pedestrian Signal Devices." until further research can be conducted and a consensus reached on the methodology to be used.

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1108 Detectable Warning Surfaces

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1108.1.1 Dome Size. Truncated domes in a detectable warning surface shall have a base diameter of 0.9 inches (23 mm) minimum to 1.4 inches (36 mm) maximum, a top diameter of 50% of the base diameter minimum to 65% of the base diameter maximum, and a height of 0.2 inches (5 mm).

Background
ADAAG states "3.1 Graphic Conventions. Graphic conventions are shown in Table 1. Dimensions that are not marked minimum or maximum are absolute, unless otherwise indicated in the text or captions. 3.2 Dimensional Tolerances. All dimensions are subject to conventional building industry tolerances for field conditions." The standard gives no tolerances for dimensions due to normal wear. It could be argued that any reduction in height of the truncated dome would put out of compliance for height requirements. "Conventional building industry tolerances" are of no help due to normal wear.

Recommendation
Modify this section as follows. 1108.1.1 Dome Size. Truncated domes in a detectable warning surface shall have a base diameter of 0.9 inches (23 mm) minimum to 1.4 inches (36 mm) maximum, a top diameter of 50% of the base diameter minimum to 65% of the base diameter maximum, and a height of 0.2 +/- 0.1 inches (5 mm).


Respectfully submitted

Tarno Coleman, PE