Trail Types and Standards

Information

PBOT adheres to the trail standards outlined in Trail Type A, Type C, and Type J as defined by the Portland Parks & Recreation's 2009 Trail Design Guidelines.

Trail Type A – Hiking (high challenge)

Definition: These trails are steep, narrow, irregular routes that may include steps and obstacles such as rocks and roots. They are located where accessible trails would have unacceptable impacts to the site and where the natural setting lends itself to a low impact trail. This type of trail may not be appropriate in areas where the resource value of the site is exceptionally high. Although used in limited hillside settings, they require higher physical exertion and increase the diversity of trail experience.

Users: The high challenge hiking trail is strenuous and requires good balance and moderate to high fitness

Accepted Materials: Native soil and rock are most common although steps, railings, and boardwalks are used as needed.

Requirements:

CharacteristicRequirement
Width18" - 30"
SurfaceSoil/stairs
Longitudinal Slope0 - 15% (short segments steeper than 15%)
Cross-Slope2% min. - 4% max.
RadiusN/A - switchbacks
Sight DistanceLimited, consider safety needs
Easement WidthTread +10' min.
Side SlopeVaries
Vertical Clearance8'
Horizontal Clearance2' from side of tread

Trail Type C - Hiking (accessible)

Definition: PP&R’s accessible hiking trails have surface, slopes, and width that meet or exceed the dimensions of the Forest Service Trail Accessibility Guidelines (FSTG). Trails with a longitudinal slope of less than 1 vertical to 20horizontal and cross-slope that is less than or equal to 2% can be traversed by wheelchairs. Trail surfaces are firm and stable. Barriers such as steps, rocks or roots do not exist although the natural surface may have some irregularities, not to exceed 2” high. The goal is to provide access to natural settings without adding pavement. Path width is minimized unless high use is expected. Landings or wider portions of the trail are provided for resting and passing other trail users.

Users: The accessible hiking trail requires fair balance and fitness. Single-file walking and (sometimes) running are desired use at minimum width. Wheelchairs (motorized or human-powered) and mobility scooters may be used, but surface is not as reliably firm and slip-resistant as a paved walking trail.

Accepted Materials: Native soil and rock are most common although crushed rock or wood fiber are used as needed. Hand or guard railings and boardwalks may be added if necessary. Excellent drainage and gravel may be necessary at wet sites to provide slip-resistant surface through winter. Fibar is the brand name of an engineered, interlocking wood fiber that is accessible to wheeled modes. Equivalent products produced locally may be substituted. Wood chips biodegrade and are difficult to maintain so provide width for hauling additional material.

Requirements:

CharacteristicRequirement
Width4' (with passing areas) - 10'
SurfaceSoil, gravel, Fibar (or engineered wood fiber equivalent), wood chips
Longitudinal Slope0-5% (8% for max. 50')
Cross-Slope2%
RadiusAesthetic consideration
Sight DistanceN/A except road crossings
Easement WidthTread + 10' min.
Side SlopeVaries
Vertical Clearance8'
Horizontal Clearance2' from side of tread

Trail Type J – Hiking and Mountain Biking

Definition: Shared hiking and biking trails have surface and slope for both mountain bike and hiker. Additional width allows side-by-side hiking or riding or room for on-coming or overtaking trail users. There are no barriers such as steps, rocks or roots although the natural surface may have some irregularities. The goal is to provide access to natural settings without adding paving.

Users: The hiking and biking trail requires moderate balance and fitness. Walkers, mountain bikers, and runners are desired users. Since this trail does not have the obstacles desired by expert riders, it is more suitable for beginning and less experienced mountain bikers. Wheelchairs (motorized or human-powered) and mobility scooters may be used, but the surface is not as reliably firm and slip-resistant as on a paved walking trail.

Accepted Materials: Native soil and rock are most common although crushed rock and boardwalks are used as needed. Curves may need to be superelevated (banked) and reinforced to resist soil displacement. Trail beds can also be armored with larger rocks in braking sections to reduce formation of brake bumps. Curve radii and sight lines should be adequate to serve two-way travel. Path width is minimized unless high use is expected or maintenance vehicle access is needed. Hand or guard railing may be added in some areas for safety. Seasonal trail closures to mountain bikes may be needed to prevent erosion.

Requirements:

CharacteristicRequirement
Width4' (with passing areas) - 10'
SurfaceSoil, gravel
Longitudinal Slope0 - 5% (to 12% if needed)
Cross-Slope2%
Radius10' min.
Sight Distance40 - 100' depending on speed / flow
Easement WidthTread + 10' min.
Side SlopeVaries
Vertical Clearance8' (avoids e-zone review)
Horizontal Clearance1' from side of tread

Exceptions to Standards

In limited circumstances, there are exceptions to these trail standards. However, they are required to be reviewed by the trails team.

Looking for additional resources? Visit our Community Partners page and the Portland Parks and Recreation Trail Design Guidelines Document