Agenda - Public Works Committee - 09/20/2005

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Detectable Warnings at Curb Ramps Is your city thi~tking of cttrb construction, reconstruction or road resm~tcing this spring? Accessibility guidelines currently require'that state and local govermrtents install detectable warnings when constructing or substantially altering curb ramps. In addition, the Federal Highway Administration and the Mi~mesota Department of Transportation (MnDOT) currently require use of detectable warnings when curb ramps are constructed or altered or roads are resurfaced on MnDOT, state aid or federal aid projects. This article offers an overview of detectable warnings and some background on the law. bVhat are detectable warnings and why are they needed? The offici.al definition of detectable warnings is "a standardized surface feature built in or applied to walking surfaces or other elements to warn visually impaired people of hazards on a circulation path." With the elimination of curbs, and common use of curb ramps, pedestrians with impaired or no vision find it much more difficult to locate the potentially dangerous intersection of sidewalks and streets. Detectable warnings function like a stop si~ for those with impaired vision; they are small, flattened bumps or "truncated domes" placed in the concrete on curb ramps. These truncated domes underfoot physically alert pedestrians with little or no vision that they are approaching a hazardous area, such as a street. According to some sources, the truncated domes are the only surface that is detectable to pedestrians who are blind, either under foot or by use of a cane. Detectable warnings must also visually contrast with surrounding surfaces so that pedestrians with low vision perceive the upcoming change from sidewalk to street. Is this a new requirentent? This provision in accessibility guidelines is not brand new. Detectable warnings were first required in 1991 but the requirement was suspended for ten years to conduct research on durability and pedestrian's ability to detect various surfaces. In 2001, the federal Architectural and Transportation Barriers Compliance Board (the Access Board), the Department of Justice, and the Department of Transportation allowed the suspension to expire. Therefore, since July 2001, detectable warnings have been required in local government construction or alteration projects. Does this ADA requirement apply to all sidewalk or street alterations? All newly constructed projects in the public right-of-way are subject to accessibility guidelines including the requirement for detectable warnings. In addition, curb ramps with truncated domes are required on all MnDOT, state aid or federal aid projects during construction, alterations, or when roads are resurfaced. In other projects, the scope of the addition or alteration may determine if the accessibility guidelines apply. Generally speaking, in order to increase accessibility, the more extensive the project, the more likely the guidelines apply. The Access Board has a technical assistance memo on the