Marion Barber, P.E.
|October 9, 2002|
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Marion Barber, P.E.
FHWA - Wyoming Division
FEDERAL HIGHWAY ADMINISTRATION
Wyoming Division Office
FROM: Marion Barber, Operations Engineer
SUBJECT: 36 CFR Parts 1190 & 1191 [Docket No. 02-1] RIN 3014-AA26, Draft Guidelines
In reviewing the proposed AADAG draft guidelines for Chapter 11, Public
Rights-of-Way, the Wyoming FHWA Division Office submits the following comments.
The “discussion of provisions” provides excellent interpretation of how the guidelines are to be applied or not applied (optional) with regards to the defined scope of work. This information however, has not been carried through in the language of the law.
How will Chapter 11 be formulated to ensure the legal interpretation allows application flexibility based on project scope of work?
Additions and Alterations
The following comment further relates to the above “General Remark”.
As presented in the second paragraph, using the scope of a project to determine the extent to which the guidelines apply is the correct approach. However, this section then proceeds to undermine this intent with the use of phrases such as “what is feasible in a given alteration will depend on a wide range of factors particular to the project” and “compliance to the maximum extent possible.” The section then goes to a guide on how to apply the guidelines in alteration projects. This section should strictly limit its application to those alterations within the scope of the project.
Alternate Circulation Path (1102.3, 1111)
The draft guidelines state that alternate circulation paths are to be located on the same side of the street parallel to the disrupted pedestrian access route. Due to ROW restrictions, this may be technically infeasible. When safety is a concern, a well-designed/signed alternate route within the immediate vicinity should be allowed when provided for both the disabled and non-disabled alike.
Minimum Clear Width (1103.3)
The draft guidelines state that a 48-inch minimum width is required, greater than the current 36-inch width. Reconstruction may not allow this increase due to existing fixtures and elements. A 48-inch sidewalk would only be acceptable if allowance for isolated areas to, accommodate existing fixtures and elements, were permissible.
Detectable Warnings (1104.3.2)
The committee suggests that detectable warnings be required only where the ramp slope is 1:15 or less. Unless this is intended to minimize the need for detectable warnings in communities with continuous rolled curbs (i.e. no separate drive way invert), this requirement would only add another dimension to what are complicated regulations.
Other Requirements for Curb Ramps and Blended Transitions (1104.3.3-1104.3.7)
The draft guidelines prohibit the placement of grates, storm drain, …… and portions of the gutter within the pedestrian access route. This section needs to limit these requirements to “new construction”.
Pedestrian Crossings (1102.8, 1105)
The draft guidelines state that marked crosswalks are to be at least 96 inches wide. This seems excessive for minor crosswalks that are infrequently used. Specifying a 96-inch wide cross walks for high volume pedestrian traffic areas and 72-inch wide cross walks for low volume pedestrian traffic areas should be considered.
The draft guidelines state the roadway cross walk, cross slope is limited to 1:48, except at mid-block crossings. Except in cities with relatively flat terrain, the existence of 1:48 (2 percent) maximum cross slopes at intersection cross walks rarely exists. With the exception of new construction in an undeveloped area, this requirement not only may be technically infeasible but also cost prohibitive. We suggest that this requirement be changed to 1:20 (5 percent).
Pedestrian Overpasses and Underpasses (1105.5)
The draft guidelines state that an elevator is required for elevation changes of 60 inches or more. It appears that this will be cost prohibitive in not only construction but also maintenance and may have a negative result in reducing the number of overpasses and underpasses considered for construction.
The draft guidelines state that continuous barriers (guardrail) are required along the street side of sidewalks where pedestrian crossings are prohibited in roundabouts. It is unclear why this situation is different than a typical winding street with sidewalks. It is well documented that the site impaired are capable of taking their cue from the presence of curbs. This guideline appears to be excessive. It may result in snow drifting, be visually unacceptable to the locals, and create other undesirable effects. As shown in the report photo, there are other ways to provide cues for the sight impaired such as grass medians with curbs. Alternative guidelines are suggested to state that a detectable warning strip is required verses a continuous barrier.
Thank you for the opportunity to comment.
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