by B Designs · 1999 · Cited by 4 — 1.1 Accessibility Legislation and Access Design Standards Prior to the ADA .. 1. 1.1.1 American National Standards Institute (ANSI) A117.1 .
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Designing Sidewalksand Trails for Access Part I of II: Review of Existing Guidelines and Practices Program Manager: Barbara McMillenAuthors:Beneficial Designs, Inc. Peter W. Axelson, M.S.M.E., A.T.P. Denise A. Chesney, M.E., B.M.E. Dorothy V. Galvan Julie B. Kirschbaum, B.A. Patricia E. Longmuir, M.S.C. Camille Lyons, B.A. Kathleen M. Wong, B.A. Illustrations:Matthew J. Boisseau, B.S. Clay ButlerDate:July 1999
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Notice:This document is disseminated under the sponsorship of the U.S. Department ofTransportation in the interest of information exchange. The United States Government assumes no liability for its contents or use thereof. The contents of this report reflect the views of the contractor, who is responsible for the accuracy of the data presented herein. The contents do not necessarily reflect the official policy of the Department of Transportation. This report does not constitute a standard, specification, or regulation. The United States Government does not endorse products or manufacturers. Trade or manufacturers™ names appear herein only because they are considered essential to the object of this document.Designing Sidewalksand Trails for Access Part I of II: Review of Existing Guidelines and Practices Acknowledgement: Julie Kirschbaum was the project coordinator for this report, and for the last two years, has focused on the development of this document.
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iTable of Contents Table of Contents List of Figures. ..vList of Tables.. ..ixIntroduction. .xi1.Disability Rights Legislation and Accessibility Guidelines and Standards in the United States 11.1Accessibility Legislation and Access Design Standards Prior to the ADA..1 1.1.1American National Standards Institute (ANSI) A117.1.1 1.1.2The Architectural Barriers Act (ABA).2 1.1.3The Rehabilitation Act.3 1.2The Americans with Disabilities Act (ADA)4 1.2.1Americans with Disabilities Act Accessibility Guidelines (ADAAG)4 1.2.2Implementing Regulations for Title II and Title III..5 1.2.3ADA Regulations that Apply to Public Entities.6 1.2.4ADA Regulations for Places of Public Accommodation and Commercial Facilities..6 1.3Accessibility Guidelines, Requirements, and Standards for Sidewalks and Trails8 1.3.1Sidewalks8 1.3.2Trails.9 1.3.3Access to Wilderness Areas10 1.4Conclusion..11 2.Characteristics of Pedestrians. 132.1Older Adults14 2.1.1Safety.14 2.1.2Ambulation.15 2.1.3Object Manipulation..15 2.1.4Visual and Cognitive Processing.15 2.2Children15 2.3People with Disabilities16 2.3.1People with Mobility Impairments.16 2.3.1.1Wheelchair and scooter users..16 2.3.1.2Walking-aid users..19
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iiTable of Contents 2.3.1.3Prosthesis users..20 2.3.2People with Sensory Impairments..20 2.3.2.1People with visual impairments.21 2.3.2.2People with hearing impairments..23 2.3.3People with Cognitive Impairments..23 2.4Conclusion..23 3.Summary of the Planning Process .253.1Intermodal Surface Transportation Efficiency Act and Transportation Equity Act for the 21st Century25 3.2Building a Multi- and Intermodal System..25 3.3Federal Transportation Funding Opportunities.26 3.4Planning under Federal Transportation Legislation27 3.5Transportation Agencies..27 3.6Land Management Agencies.28 3.7Pedestrian/Bicycle Coordinators.28 3.8Other Transportation Planning Participants28 3.9Strategies for Public Involvement29 3.10Community Impact Assessment..30 3.11Conclusion..30 4.Sidewalk Design Guidelines and Existing Practices.. 314.1Location Research..31 4.2Design Guideline Comparisons32 4.3Access Characteristics..32 4.3.1Grade.32 4.3.2Cross-Slope.35 4.3.3Width.36 4.3.4Passing Space and Passing Space Interval..38 4.3.5Vertical Clearance38 4.3.6Changes in Level.39 4.3.7Grates and Gaps39 4.3.8Obstacles and Protruding Objects40 4.3.9Surface..41 4.4Sidewalk Elements..41 4.4.1Curb Ramps41
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iiiTable of Contents 4.4.1.1Curb ramp components..42 4.4.1.2Curb ramp specifications42 4.4.1.3Curb ramp types.44 4.4.1.4Curb ramp placement..46 4.4.1.5Curb ramps and people with visual impairments..48 4.4.2Conveying Information to Pedestrians with Visual Impairments48 4.4.2.1Raised tactile surfaces used as detectable warnings50 4.4.2.2Raised tactile surfaces used for wayfinding.51 4.4.2.3Materials with contrasting sound properties52 4.4.2.4Grooves..52 4.4.2.5Contrasting colors for people with low vision52 4.4.2.6Audible and vibrotactile pedestrian signals.53 4.4.2.7ADAAG requirements for detectable warnings.54 4.4.3Driveway Crossings55 4.4.4Medians and Islands..57 4.4.5Crosswalks..57 4.4.6Crossing Times.59 4.4.7Pedestrian-Actuated Traffic Controls59 4.4.8Midblock Crossings60 4.4.9Sight Distances.61 4.4.10Grade-Separated Crossings.62 4.4.11Roadway Design..63 4.4.12Drainage64 4.4.13Building Design65 4.4.14Maintenance66 4.4.15Signs..68 4.5Conclusion..69 5.Trail Design for Access.. 755.1Universal Trail-Assessment Process..75 5.2Design Guideline Comparisons75 5.3Trail Types..76 5.4Access Characteristics..77 5.4.1Grade.77 5.4.2Rest Areas79
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ivTable of Contents 5.4.3Cross-Slope.79 5.4.4Width.80 5.4.5Passing Space81 5.4.6Changes in Level.81 5.4.7Vertical Clearance82 5.4.8Surface..82 5.4.9Trail Information.83 5.4.10Maintenance84 5.5Design Conflicts..85 5.5.1Trail Elements85 5.5.2Built Facilities Along Trails85 5.5.3Designing Trail Amenities for Multiple User Groups..86 5.5.4Drainage Control Measures and Access..86 5.5.5Complying with Design Standards.87 5.5.6Difficulty Ratings for Trails87 5.6User Conflicts87 5.6.1Experience Level.87 5.6.2Expectations88 5.6.3Conflicts Among User Groups.88 5.6.3.1Technology differences..88 5.6.3.2Movement patterns88 5.6.3.3Perceived environmental impact89 5.6.3.4New and newly popularized sports..89 5.6.4Lack of Communication Among Trail Users.89 5.6.5Number of Users..90 5.6.6Minimizing User Conflicts on Trails.90 5.7Conclusion..91 Appendix A: Abbreviations and Acronyms. 111Appendix B: Glossary 113Appendix C: Bibliography. 121
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viList of Figures Figure 4-13:Obstacles mounted on posts should not protrude more than 0.305 m (12 in) into a circulation corridor[ADAAG, Figure 8(d), U.S. Access Board, 1991].40 Figure 4-14:Components of a curb ramp42 Figure 4-15:Alternative slope profiles for alterations when an 8.33 percent slope is not achievable..42 Figure 4-16:This wheelchair user is maneuvering successfully at a curb ramp because a level landing is provided43 Figure 4-17:This wheelchair user will have difficulty entering the sidewalk because the curb ramp lacks a landing.43 Figure 4-18:This wheelchair user will have difficulty traveling around the corner because the curb ramp lacks a landing..43 Figure 4-19:Flares provide a sloped transition between the ramp and the surrounding sidewalk and are designed to prevent ambulatory pedestrians from tripping44 Figure 4-20:Returned curbs may be used when the curb ramp is located outside the pedestrian walkway, such as in a planting strip..44 Figure 4-21:Without level landings, perpendicular curb ramps are problematic for wheelchair users and others to travel across44 Figure 4-22:Two perpendicular curb ramps with level landings maximize access for pedestrians at intersections45 Figure 4-23:If diagonal curb ramps are installed, a 1.220-m (48-in) clear space should be provided to allow wheelchair users enough room to maneuver into the crosswalk..45 Figure 4-24:Parallel curb ramps work well on narrow sidewalks but require users continuing on the pathway to negotiate two ramp grades..46 Figure 4-25:A combination curb ramp is a creative way to avoid steep curb ramps and still provide level landings46 Figure 4-26:Built-up curb ramp with drainage inlets..46 Figure 4-27:Built-up curb ramp with a drainage pipe.46 Figure 4-28:To avoid having to negotiate changing grades and changing cross-slope simultaneously, a wheelchair user has to turn at the grade transition.47 Figure 4-29:Curb ramps designed with the ramp perpendicular to the curb eliminate rapidly changing grades and cross-slopes at the grade transition.48 Figure 4-30:Truncated domes are an effective way of indicating a drop-off at transit platform.50 Figure 4-31:Colored stone sidewalks with concrete curb ramps have a detectable color change.52 Figure 4-32:Driveway crossings without landings confront wheelchair users with severe and rapidly changing cross-slopes at the driveway flare55
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viiList of Figures Figure 4-33:When sidewalks have a planter strip, the ramp of the driveway does not interfere with a pedestrian™s path of travel..55 Figure 4-34:On wide sidewalks, there is enough room to provide a ramp for drivers and retain a level landing for pedestrians.56 Figure 4-35:Jogging the sidewalk back from the street provides a level landing for pedestrians on narrow sidewalks.56 Figure 4-36:Although parallel driveway crossings provide users with level landings, users continuing on the sidewalk are forced to negotiate two ramps..56 Figure 4-37:Inaccessible sidewalk caused by many individual parking lots56 Figure 4-38:Improved accessibility created by combining parking lots and reducing the number of entrances and exits.56 Figure 4-39:Cut-through corner island and center median (based on OR DOT, 1995)..57 Figure 4-40:Ramped corner island and cut-through median (based on OR DOT, 1995)..57 Figure 4-41:Two horizontal lines are the most common crosswalk markings58 Figure 4-42:A ladder design was found to be the most visible type of pedestrian crosswalk marking..58 Figure 4-43:Diagonal markings enhance visibility58 Figure 4-44:A large, easy-to-press button makes pedestrian-actuated traffic controls more usable for people with limited hand strength and dexterity..60 Figure 4-45:Curb extensions at midblock crossings help reduce crossing distance..61 Figure 4-46:Sight line obstructed by parked cars prevents drivers from seeing pedestrians starting to cross the street61 Figure 4-47:Partial curb extensions improve visibility between pedestrians and motorists62 Figure 4-48:Full curb extensions improve visibility between pedestrians and motorists62 Figure 4-49:Pedestrian and biker underpass.62 Figure 4-50:When roads are not milled, layers of asphalt build up and make the crossing difficult for wheelchair users and others..64 Figure 4-51:Milling roads from gutter to gutter prevents rapidly changing grades and makes intersections easier for wheelchair users to negotiate.64 Figure 4-52:Stairs bridging low street elevation and high finished-floor elevation prevent wheelchair access into the building..65 Figure 4-53:Steep cross-slopes bridging low street elevation and high finished-floor elevation make the sidewalk difficult for wheelchair users to travel across..65
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viiiList of Figures Figure 4-54:A level area at least 0.915 m (36 in) wide improves access when there is a low street elevation and high finished-floor elevation..66 Figure 4-55:A higher curb provides a level pathway but might increase the slope of curb ramps if the sidewalk is narrow.66 Figure 4-56:Traffic sign indicating upcoming steep grade (US DOT, 1988)..68 Figure 4-57:Pedestrian sign indicating upcoming steep grade68 Figure 5-1:Outdoor recreation access routes (ORARs) link accessible elements at a recreation site.76 Figure 5-2:Trails often have maximum grades that are significantly steeper than typical running grades77 Figure 5-3:Well-designed switchbacks reduce the grade of a trail and make hiking easier for people with mobility disabilities.78 Figure 5-4:Rest areas enhance the trail for all users..79 Figure 5-5:Tree roots that break up the surface of the trail should be removed because they can cause users to trip82 Figure 5-6:The vertical clearance of a trail should depend on the designated user groups..82 Figure 5-7:Soft surfaces are difficult for people with mobility impairments to negotiate and therefore should be avoided83 Figure 5-8:If a trail is accessible, the trail elements along the path also should be accessible..85 Figure 5-9:Rubber waterbars are difficult for wheelchair users and bikers to push down when traveling uphill, but they are still more desirable than inflexible waterbars.86 Figure 5-10:Swales can control drainage and eliminate the need for waterbars86 Figure 5-11:Separate pathways and clear signage can help reduce conflicts between users who travel at different speeds.89 Figure 5-12:Trail signs can help clarify trail etiquette90
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ixList of Tables List of Tables Table 1-1:Developments in Disability Rights Legislation and Accessibility Guidelines from 1961 to 19982 Table 2-1:Highest Reach for Wheelchair Users (based on Steinfeld, Schroeder, and Bishop, 1979)18 Table 2-2:Eye-Level Measurements for Wheelchair Users (based on Steinfeld, Schroeder, and Bishop, 1979)19 Table 4-1:Grade, Cross-Slope, and Curb Height Guidelines by Functional Class of Roadway (based on information contained in AASHTO, 1995)63 Table 4-2.1:Federal Accessibility Guidelines for Accessible Routes.70 Table 4-2.2:ADAAG-Proposed Section 14 (1994) Accessibility Guidelines for Public Rights-of-Way70 Table 4-2.3:State Guidelines for Sidewalks.71 Table 4-2.4:Additional Recommendations for Sidewalks71 Table 4-3.1:Federal Accessibility Guidelines for Curb Ramps (CR).72 Table 4-3.2:ADAAG-Proposed Section 14 (1994) Accessibility Guidelines for Curb Ramps (CR)72 Table 4-3.3:State and City Guidelines for Curb Ramps (CR)73 Table 4-3.4:Additional Recommendations for Curb Ramps (CR)..73 Table 5-1:Results of 10 Trail Assessments Show That on Many Trails, the Maximum Grade and Cross-Slope Significantly Exceed the Typical Average Grade and Cross-Slope (Chesney and Axelson, 1994)..77 Table 5-2:Cross-Slope Ranges by Surface Type (AASHTO, 1995)80 Table 5-3:Scoping Requirements for Accessible Parking Spaces.85 Table 5-4.1:Federal Accessibility Guidelines for Maximum Allowable Running Slope without Landings and Handrails.92 Table 5-4.2:Federal Advisory Committee Recommendations for Maximum Allowable Running Grade92 Table 5-4.3:Federal Guidelines for Maximum Allowable Running Grade..92 Table 5-4.4:State, County, and City Guidelines for Maximum Allowable Running Grade..93 Table 5-4.5:Additional Recommendations for Maximum Allowable Running Grade..94 Table 5-5.1:Federal Accessibility Guidelines for Maximum Slope for a Specified Ramp Run with Landings and Handrails..95 Table 5-5.2:Federal Advisory Committee Recommendations for Maximum Grade for a Specified Distance (Run)95
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