DRAFT Comprehensive Transportation Plan Update: February 23, 2018 version

MULTI -USE PATH

DESIGN

GUIDELINES

Longitudinal Grades Longitudinal grade is also referred to as running grade. In 2011, the United States Access Board (USAB) issued the Advance Notice of

Proposed Rulemaking (ANPRM) on Accessibility Guidelines for Shared Use Paths and, in 2013, a supplemental notice of rulemaking (SNPRM)

to provide clarification on the longitudinal grade requirements. Table F-4 provides regulatory constraints that would include federal, state,

or local laws with the purpose of preserving threatened or endangered species; the environment; or archaeological, cultural, historical, or

significant natural features that would be adversely affected by the additional gradient. However, USAB acknowledged that there will be

circumstances in which full compliance with the grade requirements may not be practical due to physical or regulatory constraints. Physical

constraints would include existing terrain or infrastructure, right-of-way availability, notable natural features, or any similar existing physical

constraint. The suggested minimum longitudinal grade is 0.5 percent. The information below provides more clarity about special cases for

implementation.

Guidelines  Multi-use paths will not exceed the general grade established for the adjacent street or highway, within a highway or street right-of-

way.

 Maximum 5% grade within a highway or street right-of-way.

Table F-4. Maximum Running Slope and Segment Length when Physical or Regulatory Constraints Exist

RUNNING SLOPE OF TRAIL SEGMENT MAXIMUM LENGTH OF SEGMENT

Steeper Than

But Not Steeper Than

1:20 (5%)

1:12 (8.33%)

200 feet 30 feet 10 feet

1:12 (8.33%)

1:10 (10%)

1:10 (10%)

1:8 (12%)

If the terrain requires steep runs longer than the allowable distance, resting intervals need to be provided at the top and bottom of each

segment. A resting interval is also required any time the running slope exceeds 1:20 (five percent). Resting intervals may be provided within

or adjacent to the path tread. When the resting area is within the path tread, it must be 60 inches long and at least as wide as the path.

When the resting area is adjacent to the path, it must be 60 inches long and 36 inches wide and provide a minimum 4-foot by 4-foot

turning space. The surface of the resting area cannot exceed 1:48 (two percent) in any direction.

Ramps and Landings Curb ramps provide access between the multi-use path and roadway for people using wheelchairs, strollers, walkers, crutches, handcarts,

bicycles, and for pedestrians with mobility impairments who have trouble stepping up and down high curbs. Curb ramps must be installed

at all intersections and midblock locations where pedestrian crossings exist, as mandated by federal legislation (1973 Rehabilitation Act and

1990 Americans with Disabilities Act). The running slope of a curb ramp must not exceed 1:12 (8.33%).

Guideline s  Detectable warnings need to be placed across the path width, adjacent to the roadway.

 Proposed Rights of Way Accessibility Guidelines (PROWAG) states handrails are required on ramp runs with a rise greater than

6 inches, but are not required for pedestrian circulation paths.

 Any side flares associated with the ramp must be outside the path width.

Figure F-6. Typical Pavement Structural Sections for Multi-Use Paths

Surface Material The specific pavement section for multi-use paths is dependent on the site-

specific soils, loads, and construction practices. According to AASHTO, cement

concrete typically has a longer service life, reduced susceptibility to cracking and

deformation from roots and weeds, and a more consistent riding surface after

years of use and exposure to natural elements. A drawback of cement concrete

pavements is that pavement markings (such as centerlines) can have a lower

contrast against the concrete surface. Asphalt includes a smooth surface, but is

less durable with a typical life expectancy of 15-20 years. Unpaved surfaces are

typically only appropriate on rural paths, where the intended use of the path is

primarily recreational, or as a temporary measure to open a path before funding is

available for paving. Within the Town of Morrisville asphalt should be used for

paths outside of roadway rights-of-way, and concrete should be used for paths

within roadway rights-of-way. Figure F-6 on this page shows a range of

materials that may be used for multi-use paths.

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