Jay McCoy, P.E.
|October 28, 2002|
Comments to Draft Guidelines on Accessibility of Public Rights-of-Way
I appreciate the opportunity to comment on the draft guidelines. While I concur that the ADA needs more clarity in the area of the Public Right-of-Way, I have some serious concerns with some of the guidelines proposed.
Section 1104.2.1 and 1104.2.2 requiring level landings is and has been a problem in numerous applications locally, particularly where two ramps were built per corner. What we have run into is when you have streets with steep grades at the gutter line, then when you project out to the outside edge of the sidewalk, you end up with an extremely steep transition from the one level landing to the other. Basically at the back of sidewalk, which may be 15 feet from gutter, the elevation differences get magnified. Where you may have had 15' between ramps at gutter line to drop 1'; at back of sidewalk, you now only have only 1' between landings to drop the same 1' elevation. The requirement for level landings needs an exemption where existing street grades are too steep to safely provide those level landings.
Section 1105.2 requiring the 2% crosslope maximum on intersection crosswalks seems an awkward requirement at best. In urban areas where it is not uncommon to have a public street intersection every 200 to 400 feet, this requirement will result in a very uneven roadway profile. While this could be of some benefit to keep vehicle speeds slow in downtown areas, it could potentially lead to operational problems on higher speed roadway with steeper grades. Additionally when combined with the additional width of the crosswalks proposed, the elevation differences will have to be made up outside of the intersection, leading to roadway profiles that would be steeper than that required by the terrain (e.g. for a 200' long block at a natural grade of 9%, would effectively end up at 10% with this requirement). The problem created with the steepening of the effective grade does not justify the proposed change.
Section 1105.3 requiring pedestrian signal phases to be calculated at 3 feet per second universally is a bad idea. That is and should continue to be a decision that is discretionary to the local road authority. By potentially requiring more travel lanes to meet level of service requirements, this proposal would lead to wider intersections. Even if dollars were unlimited and we could add the lanes necessary to meet level of service standards, is that really what we want to do? Wider intersections lead to longer crossing times, putting the pedestrian in danger for a longer period of time. Given the lack of financing being reported around the country, instituting such a requirement that will have a profound effect on intersection timing and subsequent lane configurations, is in my opinion unwise.
Section 1105.5 requiring elevator access where the ramped approach exceeds 60 inches seems to be ill advised as well. Where there may be high-profile, high-budget projects out there that this may be applicable to, requiring it wherever a pedestrian overpass/underpass is proposed will only serve to detract from such an option. Local road authorities with limited budgets, can not afford to construct, let alone maintain such facilities. By effectively removing overpasses/underpasses from the roadway designers tool box will not serve the pedestrian community. More out of direction travel or less safe at-grade facilities will be the only affordable alternatives remaining.
Section 1105.6 requiring pedestrian activated crossing signals at each roundabout crosswalk fails to recognize the fundamental requirement for a roundabout. Roundabouts are known to be safer than signalized intersections. But they require that there is no downstream signal that will cause queued vehicles to back up into the roundabout. This proposal would effectively cause a roundabout to operate unsafely. It hardly makes sense to enhance safety for one segment of the population while making it unsafe for another. Again, such a requirement will only serve to remove the roundabout form the engineer's toolbox. Given the success of the modern roundabout in this country and abroad, that would be a shame.
Section 1102.14 requiring at least one accessible on-street parking space per block face is problematic. This requirement would effectively reduce on-street parking in some downtown areas (with 200' long blocks) by 25%. With the parking shortages typical in downtown areas and the financial problems with many of our police departments, regulations that serve to increase demand for legal parking spaces and thereby increase violations without corresponding resources for enforcement, seems like a recipe for trouble. Additionally, the safety issues of an accessible on-street parking space on higher speed streets without the adjoining access aisle would be of concern to me.
Section 1102.3 requiring an alternate circulation path on the same side of the street is also not well thought out. By mandating that this access is provided, subsequent construction costs will go higher. Given that construction dollars are fixed, is this really the way the ADA community wants those dollars spent. In other words, this will cause project costs to increase, thereby reducing what actually gets built permanently, or in the worst case, making a project impractical to build at all. It is not uncommon in transportation projects to completely close down a roadway for a short period of time so the project can be built quicker, resulting in less inconvenience to the traveling public.
Section 1105.4.2 requiring detectable warnings at cut-through islands to have a 24 inch separation essentially requires minimum median island widths of 6 feet (the minimum detectable warning width is also 24 inches). That means where we could build a 4' island refuge before, now under this proposal we could not. That seems to me counterproductive. Again, the net effect is a loss of safety for the pedestrians.
Jay McCoy, P.E.
Department of Environmental Services
City of Gresham [OR]
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