Skip to content U.S. Department of Transportation/Federal Highway AdministrationU.S. Department of Transportation/Federal Highway Administration

Office of Planning, Environment, & Realty (HEP)
PlanningEnvironmentReal Estate

HEP Events Guidance Publications Awards Contacts

Designing for Nonmotorists

Designing Shared Use Paths and Trails, continued

Return to Page 1  ·  Return to Presentation Index


Shared Use Paths: Surface

Surface: Firm, stable, and slip resistant.

  • Must accommodate wheelchairs.
  • Accommodate narrow-tire bicycles.
  • Accommodate people pushing baby strollers (good "test equipment").
  • Pavement is not required. Pavement may not be appropriate in some settings (rural).
  • Slip resistance required, but may be difficult on unpaved surfaces.
    • Slip resistance was not required in the Outdoor Developed Areas Guidelines.

Shared Use Paths: Surface

  • There are no Federal laws or regulations that require a shared use path to be paved.
Photo of equestrians riding and people walking along a trail.
Photo of people jogging and pushing a baby stroller along a trail.
Photo of people walking and running along a trail.
Photo of two women in Amish garb inline skating along a trail.
Photo of a person riding a bike passing and waving to a passing horse and buggy.

Photo source: Stuart Macdonald, American Trails.
Top left: High Line Canal Trail, Cherry Hills Village, CO.
Photo by Stuart Macdonald, American Trails, Crusher fines surfacing for trails
Top middle: Town Lake Trail, Austin TX. Photo by Stuart Macdonald, American Trails.
Bottom left: High Line Canal Trail, Cherry Hills Village, CO. Photo by Stuart Macdonald, American Trails.
Bottom middle: Holmes County, Ohio. Source: Holmes County Park District / Holmes County Rails to Trails Coalition.
Right: Holmes County, Ohio. Source: Holmes County Park District / Holmes County Rails to Trails Coalition.

Shared Use Paths: Surface

Graphic of a Rotational Penetrometer.

Drawing from Beneficial Designs.

Firm and stable.

  • Some crushed aggregates can be firm and stable.
  • Rotational Penetrometer:
    Measures firmness and stability of ground and floor surfaces.

www.beneficialdesigns.com/surfaces/surface.html#rotational


Shared Use Paths: Surface

Pavement

  • Asphalt or Concrete?
  • Asphalt often cheaper to construct, but may suffer water, frost, and tree root damage.
  • Concrete may be cheaper in the long run: may better withstand flooding, frost, roots, etc.
  • Concrete: use "saw cut" for joints.
  • Check for accessibility and a smooth surface.

Shared Use Paths: Tread Obstacles

Tread Obstacles: Avoid, Minimize, and Prevent.

  • Prevent roots, rocks, ruts, bumps, cracks, etc.
  • Maintain a smooth path: sweep, fix irregularities.
  • Exception: Detectable warnings at crossings.
Shared-use paths provide recreation and transportation opportunities for a variety of user groups including pedestrians and bicyclists. Oftentimes, surface maintenance issues are addressed in small segments rather than resurfacing the entire path. Improperly recompacted trenching can contribute to loss of control and cause the wheelchair to flip over backwards. A 610 mm (24 in) strip of detectable warnings should be installed at the edge of a raised crosswalk to identify the transition between the sidewalk and street.

From FHWA's Designing Sidewalks and Trails for Access, Best Practices Design Guide
Photo: Figure 14-1
Drawing on top right: Figure 14-7
Bottom drawing: Figure 6-8

Shared Use Paths: Gaps

Graphic showing dominant direction of travel.

Gaps: Avoid, Minimize, and Prevent.

  • Keep drainage grates off the trail.
  • Minimize: openings, pavement and bridge joints, open bridge decks, railroad crossings, boardwalks.
  • Openings shall not permit passage of a 0.5 inch / 13 mm diameter sphere.
  • Elongated openings should be perpendicular or diagonal to travel direction.

Access Board Figure R302.7.3 Horizontal Openings
Some exceptions for boardwalks for Trails, but not Shared Use Paths: 0.75 inch/19 mm.

Access Board R302.7.4 Flangeway Gaps.
Flangeway gaps at pedestrian at-grade rail crossings shall be 64 mm (2.5 in) maximum on non-freight rail track and 75 mm (3 in) maximum on freight rail track.

Shared Use Paths: Width

  • How much use will there be?
  • 8 foot minimum for low-use facilities:
    • Connectors between cul-de-sac neighborhoods.
    • To avoid inviting cut-through motor vehicles.
  • Prefer 10 foot minimum, recommend 12 foot, more if needed.
  • Avoid designing only for the minimum.
Photo of Peter Axelson in his wheelchair along a trail marked with sign detailing trail accessibility.
Photo: Peter Axelson, Beneficial Designs.
Contractor for FHWA's Designing Sidewalks and Trails for Access,
Best Practices Design Guide
.

Shared Use Paths: Width

  • High use facilities: Consider separating "heels and wheels" on two separate paths.
Photo of people on a trail with two adjacent or parallel paved treadways. Photo of a trail with two adjacent or parallel treadways; one paved another dirt track intended for equestrians.
Left photo: Pinellas County Rail-Trail, Florida. Stuart Macdonald, American Trails.
Right photo: USDA Forest Service: Equestrian Design Guidebook for Trails, Trailheads, and Campgrounds.

Shared Use Paths: Width

Passing Space

  • Accessibility requirement: At least 60 inches (1525 mm) width within 200 foot (61 m) intervals.
  • Should not be an issue for Shared Use Paths.
  • Avoid designing only for the minimum.

Passing space 1.5 m (5 ft) by 1.5 m (5 ft) min. at 61 m (200 ft) max intervals along 1.2 m (4 ft) wide min. pedestrian access route.
US Access Board: Figure R302.4 Passing Space

Shared Use Paths: Grade

Grade: Accessibility is the primary consideration.

  • Use Access Board's Shared Use Path Guidelines in the Public Rights-of-Way Guidelines.
  • Grade: <5% to the extent practicable.
  • There may be situations were "compliance is required to the extent practicable."
  • At highway crossings: Highway slope is trail cross slope, highway cross slope is trail slope.

R302.5 Grade. The SNPRM would revise R302.5 to read as follows:
R302.5 Grade. The grade of pedestrian access routes shall comply with R302.5.
R302.5.1 Within Street or Highway Right-of-Way. Except as provided in R302.5.3, where pedestrian access routes are contained within a street or highway right-of-way, the grade of pedestrian access routes shall not exceed the general grade established for the adjacent street or highway.
R302.5.2 Not Within Street or Highway Right-of-Way. Where pedestrian access routes are not contained within a street or highway right-of-way, the grade of pedestrian access routes shall be 5 percent maximum.
R302.5.3 Within Pedestrian Street Crossings. Where pedestrian access routes are contained within a pedestrian street crossing, the grade of pedestrian access routes shall be 5 percent maximum.
R302.5.4 Physical Constraints. Where compliance with R302.5.1 or R302.5.2 is not practicable due to existing terrain or infrastructure, right-of-way availability, a notable natural feature, or similar existing physical constraints, compliance is required to the extent practicable.
R302.5.5 Regulatory Constraints. Where compliance with R302.5.1 or R302.5.2 is precluded by federal, state, or local laws the purpose of which is to preserve threatened or endangered species; the environment; or archaeological, cultural, historical, or significant natural features, compliance is required to the extent practicable.

Shared Use Paths: Grade

  • Grade: <5% to the extent feasible.
  • Avoid abrupt grade changes:
    • Annoying and can be dangerous.
  • No provision or requirement for rest intervals, but could be considered on sustained grades.
Change of grade. Transitions should have minimum grade changes (less than 11%) for a gradual transition for wheelchair users. Change of grade. Transitions should have minimum grade changes (less than 11%) for a gradual transition for wheelchair users. Change of grade. When steep grades abruptly change into level landings, people who use wheelchairs and scooters are put at risk of falling forward or losing control of their device.

From FHWA’s Designing Sidewalks and Trails for Access, Best Practices Design Guide
Top left drawings: Figure 7-19
Top right drawing: Figure 14-9
Bottom drawing: Figure 14-10

Rest Intervals: A place to stop and rest. A rest area may be off to the side. From Outdoor Developed Areas: Where running slopes exceed 1:20 (5%), at intervals no greater than the lengths permitted under running slope. Size: 60 inch (1525 mm) length, at least as wide as the widest trail segment adjacent to the rest area. PROW Level Landing: 2%.

Shared Use Paths: Cross Slope

  • Cross Slope: <2%
  • At highway crossings: Highway slope is trail cross slope, highway cross slope is trail slope.
  • Superelevation? Accessibility trumps.
  • NOTE: The Outdoor Developed Areas Guidelines allow steeper cross slopes for recreational trails. Shared Use Paths must use a higher standard.

R302.6 Cross Slope. Except as provided in R302.6.1 and R302.6.2, the cross slope of pedestrian access routes shall be 2 percent maximum.
Advisory R302.6 Cross Slope. The cross slope requirements in R302.6 apply to sidewalks and other pedestrian circulation paths, pedestrian street crossings and at-grade rail crossings, and pedestrian overpasses and underpasses and similar structures (see R302.2). The cross slope of the pedestrian access route is measured perpendicular to the direction of pedestrian travel. Cross slope requirements are contained in R304.5.3 for curb ramps and blended transitions, and in R407.3 for ramps.
R302.6.1 Pedestrian Street Crossings Without Yield or Stop Control. Where pedestrian access routes are contained within pedestrian street crossings without yield or stop control, the cross slope of the pedestrian access route shall be 5 percent maximum.
Advisory R302.6.1 Pedestrian Street Crossings Without Yield or Stop Control. Pedestrian street crossings without yield or stop control are crossings where there is no yield or stop sign, or where there is a traffic signal that is designed for the green phase. At pedestrian street crossings without yield or stop control, vehicles can proceed through the intersection without slowing or stopping. Where pedestrian access routes are contained within pedestrian street crossings with yield or stop control, the cross slope of the pedestrian access route must be 2 percent maximum (see R302.6). At pedestrian street crossings with yield or stop control, vehicles slow or stop before proceeding through the intersection.
R302.6.2 Midblock Pedestrian Street Crossings. Where pedestrian access routes are contained within midblock pedestrian street crossings, the cross slope of the pedestrian access route shall be permitted to equal the street or highway grade.

Shared Use Paths: Vertical Clearance

  • Accessibility: 80 inches minimum.
  • Equestrian Use: 10 feet minimum.
Graphics showing various scenarios where branches from a tree could encroach on the trail tread impacting trail users. Graphics showing various scenarios where branches from a tree could encroach on the trail tread impacting trail users.

Left: USDA Forest Service: Equestrian Design Guidebook for Trails, Trailheads, and Campgrounds.
Top right: From FHWA's Designing Sidewalks and Trails for Access, Best Practices Design Guide
Middle right: U.S. Department of Justice, Civil Rights Division, Disability Rights Section: ADA Checklist for Polling Places, page 18.
Bottom right: FHWA's Designing Sidewalks and Trails for Access, Best Practices Design Guide.

Shared Use Paths: Vertical Clearance

  • Maintenance vehicles: 12 feet? More?
  • Provide warnings or barriers for low overhead clearance: detectable by people with visual impairments.
Photo Collage of Various scenarios where vertical clearance needs to be considered.

Stair photo: US Access Board archives.
Top stair drawing: U.S. Department of Justice, Civil Rights Division, Disability Rights Section: ADA Checklist for Polling Places, pages 17/31.
Bottom stair drawing: US Access Board, Americans with Disabilities Act and Architectural Barriers Act Accessibility Guidelines, July 23, 2004, Figure 307.4.
Right photo: Clear Creek Trail crossing under Burlington Northern Railroad embankment, Jefferson County, CO; photo by Stuart Macdonald, August 1, 2009.

Return to Presentation Index  ·  Return to Top

Updated: 10/10/2014
HEP Home Planning Environment Real Estate
Federal Highway Administration | 1200 New Jersey Avenue, SE | Washington, DC 20590 | 202-366-4000