Dave Spiegelberg, P.E.
|
October 28, 2002 |
We just received the notice of proposed Guidelines for Accessible Public Rights
of Way. We realize the importance of this matter. This e-mail is represents our
special situation and we hope our comments will be accepted as part of your
outreach. Thank you.
The proposed guidelines limit cross slope at these locations to 1:48, except at
mid block crossings. It also limits running slope to 1:20 in cross walks. For
many hilly and mountainous communities, these standards will require that a
technical feasibility analysis be performed, and subsequent findings be made on
a regular basis. Several roads in El Dorado County exceed the 1:20 running grade
(5%) on the main highway, and may exceed 12% on the side streets. It seems that
the "running grade of the road" standard should also apply at intersections,
since many intersections in hilly and mountainous terrain could be expected to
exceed these standards. Strict application of these standards would result in
greater earth disturbance, and increased environmental costs, due to creation of
"table" areas that meet the proposed requirements.
The Policy on Geometric Design of Highways and Streets, Fourth Edition,
published by the American Association of State Highway and Transportation
Officials is used extensively by local agencies across the Country to develop
and implement roadway designs and design
standards. This document provides guidance that roadways at
intersections generally should not exceed 6% (1:17), but does not prohibit
steeper grades in some instances.
Additionally, it is not uncommon for the roadway at intersections to exceed 2%
in the side street profile. In many cases, where the intersection is widened,
with signalization, sidewalks and cross-walks installed, the proposed guidelines
would require extensive reconstruction of the side street profile, to meet the
cross slope requirements of the cross walk (1:48). It would seem that a 5%
(1:20) standard for cross-walks would be more appropriate, considering that many
streets and highways throughout the Country have been designed with shoulders
constructed at 5%. In hilly terrain, this can drastically affect the costs,
environmental impacts and overall effectiveness of the intersection project.
We appreciate your consideration of these comments.