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Our Maps & Ratings

See how we map Effort, Stress, and other features of Paths, Routes, and Trails

Effort-description
Jack Markell Trail

Effort 

Read how we rate, map, and describe effort.

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Other Accessible Features

Read how we rate, map, and describe Traffic Stress

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Trail Accessibility

Read how we rate, map, and the accessibility of a trail 

PA Trail Difficulty Ratings.png

Traffic Stress

Read how we rate, map, and describe Traffic Stress

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Trail Stress

Read how we rate, map, and describe sources of Trail Stress 

Effort

Our goal is to generate descriptions to help walkers, hikers, and cyclists identify the option just right for them. Using Digital Elevation Mapping (DEM) wherever feasible (see right), we map the grade of paths and trails every 10' (and routes every 30'), which helps to to establish whether a path meets Universal Access standards. Hikers can also rely on our descriptions (see below) until maps are available.

Interested in the mechanics of our GPS mapping?

We download a GPX file corresponding to the route from Google Maps or All Trails. We generate a text file using GPS Visualizer, which can also add tick points and elevations at 10' or 30' intervals using DEMs. We manually correct DEMs thrown off by bridges and tunnels.  Where steep terrain, makes DEM inaccurate, we map elevations on the trail itself using our Garmin GPS Map 65S. A custom spreadsheet assigns grades for each interval and calculates Flat Equivalent Length. 

We mapped this shared use loop heading north (counter-clockwise) from the parking lot. You encounter moderate uphill grades almost immediately and then a 50' section of difficult grades.  Because uphill grades are less steep going in the other direction, we recommend that those who find steep uphill grades difficult consider walking this loop clockwise.

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Effort-map

Trail Stress

On Trails - Coming Soon

Traffic Stress

Bicycle levels of traffic stress (BLTS) overview... Alta provides an excellent summary of the traffic stress model for those interested in reading more. 

BLTS for each relevant road segment within an identified route are drawn from analyses conducted by Delaware Valley Regional Planning Commission (DVRPC - see right) and New Castle County.

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On our maps, higher levels of traffic stress are represented using larger circles for each 30' section.

 

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Descriptors are used in the text corresponding to the level of traffic stress as follows: Level 0 - No Stress; Level 1 - Very Low Stress; Level 2 - Low Stress; Level 3 - Moderate Stress; Level  - High Stress.

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A modified BLTS

One of the limitations of BLTS is that is was developed and has been used primarily in urban and suburban settings.  The BLTS model yet to be adapted to accommodate conditions more often found in rural settings. For sections of the route where we have additional information, we have modified the BLTS model as described below.

  • Actual prevailing speeds and/or volumes: DVRPC derives their ratings based on assumptions about speed (e.g., posted speed limits) and volume given the type of road, not on actual traffic studies. In rural regions like Kennett, drivers are more likely to speed, and volumes can sometimes be very low.  We indicate wherever actual traffic studies change BLTS. 

  • Limited Sight Distance: mmmThis used in some cases where additional information is available regarding the likely presence of sections with limited sight distance (see below) or (these models otherwise use posted speed limits and estimated volumes to model traffic stress).

Every 30' section on the route for which BLTS has been modified is outlined in red..

 like sections with limited sight distance (see below).

Limited sight sections

because of the road’s horizontal or vertical curvature, sometimes worsened by shrubs or trees. Drivers may not be able to see far enough ahead to safely pull around cyclists, increasing the risk of accidents.

We used William’s (2021) paper to establish minimum sight distances (i.e., 2 times the stopping sight distance) based on posted speed (or prevailing speed, when these data were available. Because our interest was in perceived stress as well as actual danger, we added 50’ to the minimum sight distance. Whenever a section was suspected, we measured the sight distance and increased the BLTS by 1 point at each 20’ section for which sight distance was an issue.  

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