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What barriers prevent people - especially those with disabilities - from using a trail?

Universal Access (UA) Standards for paths and trails 

1. They are complex

2. They are confusing

3. One standard but many disabilities
4. A UA trail is not always an easy trail
5. Existing Trail difficulty ratings do not work for pedestrians with mobility challenges 
What are the current standards for Universal Access (UA) Trails? 

We reference Universal Access (UA) standards across this site when describing all paths and trails used for walking and hiking. These are based on the summary provided in Trails for All People (see right), with specific page references. These guidelines review issues related to accessibility on Universal Access Trails as well as Shared Use Paths. This is especially useful for those responsible for designing paths, because of the different regulations that apply under different circumstances.

The summaries offered below are intended to orient users to general principles: those seeking to build universal access trails MUST rely on an experienced designer. 

Knudson guide full page.PNG
Standards for accessibility
1. UA Standards are complex


  • Running grades in the direction of travel (p. 30): Less than 12.5% for no more than 10'; Less than 10% for no more than 30'; less than 8.33" for less than 200' and 30% of the  trail.

  • Why? Many wheelchair user find steeper grades in the direction of travel impossible to navigate. Uphill grades can be just too hard, and controlling the descent on downhill grades can be just too stressful 

Example coming soon!

UA-Running Grades

Example coming soon!

  • Cross grades perpendicular to the direction of travel (p. 30): 5% maximum.  

  • Why? Many wheelchair user find it impossible to chart a straight course with steeper cross-grades - they may always feel like they are about the go off the trail


Tread Surface (p. 31): Must be clear, firm, and stable.

Why? Wheelchair users want a surface that is: 

  • Clear , so that they can see any small obstacles;

  • Firm,  so that they do not slip and do not sink and become stuck, and;

  • Stable, so that they can be confident that the surface is good even if the weather is not.  

Example coming soon!


Example coming soon!

Obstacles (p. 33) Must be no more than 2" high and separated by 48" on natural surface trails (standards are different for hardened trails)

Why? Higher obstacles are more challenging for wheelchair users to surmount, and quickly become impossible when spaced around the same wheelbase as a wheelchair 


Width (p. 31) Must be at least 36" at the tread.  It can decrease to 32" around a specific obstacle.  Why? A wheelchair user needs 36" to comfortably navigate, but can pass through a specific opening as little as 32" wide.

The Whitely Farm Loop in White Clay Creek State Park is at least 36" wide, though it sometimes narrows by 1-2 inches to squeeze between trees.  This is illustrated here with Margot's 32" wide special needs trailer barely squeezing through. 


Example coming soon!

Passing spaces (p. 32). At least 60" wide and 60"long, at least every 1000' for any trail less than 60" wide. 

Why? Two wheelchair users need 60" to pass each other comfortably. 

UA-Other features

Resting Intervals (p. 32). At least 60" long, at the top and bottom of segments that exceed 5%.  Why? Resting intervals give wheelchair users a chance to catch their breath on sections that approach the maximum length/grade combinations listed earlier

Example coming soon!

2. Standards referencing accessibility are confusing
Effort relative to Length %.jpg

There are different standards for Shared Use Paths and Universal Access Trails

The former (see. p. 63) must also accommodate cyclists and other users, and so are wider, have stricter requirements for grades, and are paved for other users (like those on roller-blades) - see the example of grades listed to the left. And standards for Shared Use Paths are also different when these are built in the public right-of-way.

Standards for accessibility are confusing

Trail builders must comply with accessibility standards only "to the extent practicable"

In practice, this means that Shared Use Paths and Universal Access Trails are permitted to exceed allowable grades because of the terrain, like in the example listed below. Note that those using only local or private funds to build these paths and trails have no obligation to adhere to accessibility standards, but any shared use path or universal access trail built on federal land or using federal dollars (including pass-through grants to states and counties) must strive to comply with these standards   

Sample steep descent NDG.png

CASE STUDY The descent from Alapocas Drive into Brandywine Park in the westernmost section of the Northern Delaware Greenway includes more than 160' of difficult downhill grades (up to 20%) that would make this uncomfortable for many cyclists and all but the most experienced wheelchair users.  You can see this in the grades to the left, with each dot marking a 10' section, and dark blue indicating difficult downhill grades.  Like many shared use paths, no resting intervals are provided.  

Descriptors can sometimes be ambiguous


Are related facilities - and the routes to them - accessible?


3. There is one set of standards but many different types and levels of disability


4. A trail meeting UA standards is not always an easy one

A trail does not have to be uniformly flat to meet UA standards - it can have uphill section of any length as long as these do not exceed 5%.  It can have uphill sections of 5-8.33% for up to 30', and uphill sections of 8.33-10% for up to 10'. And it can have any number of these as long as there are resting intervals in between.


Consider this beautiful 600' boardwalk section of the Jack Markell Trail.  It complies with UA standards for shared use paths because it never exceeds a 5% grade.  Nonetheless, its length would make it difficult - and potentially stressful - for less experienced or fit users.

Jack Markell Trail
UA trail is not always easy
5. Existing Trail difficulty ratings often do not work for pedestrians with mobility challenges

Some rating systems span a very wide range of difficulty, and do not offer finer distinctions important to those with mobility challenges- 

Other rating systems not only span a very wide range of lengths, but they also confound length and difficulty.

  • In the 5 point system described by the National Park Service, Level 5 includes hikes 5-8 miles long with steep inclines that would be "challenging for an unconditioned person".


Other ratings like those adopted by Pennsylvania (p. 12) and pictured to the right include more descriptors relevant to those with mobility challenges but may still be too vague. 

Our system separates out effort and difficulty or stress, and captures trails just exceeding accessibility standards.


PA Trail Difficulty Ratings.png
Trail ratings do not work
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