DRAFT Comprehensive Transportation Plan Update: 2/23/2018 version

Figure F-5: AASHTO Guide for the Development of Bicycle Facilities Minimum Length of Crest Vertical Curve

ADA COMPLIANCE ADA accessibility guidelines must reflect the Proposed Public Rights-of-Way Accessibility Guidelines (PROWAG) which is developed by the

U.S. Access Board. The PROWAG provides draft accessibility guidelines for the design, construction, and alteration of pedestrian facilities in

the public right-of-way. The guidelines ensure that sidewalks, pedestrian street crossings, pedestrian signals, and other facilities for

pedestrian circulation and use constructed or altered in the public right-of-way by state and local governments are readily accessible to and

usable by pedestrians with disabilities. Compliance with the accessibility guidelines will be mandatory when they are finalized and adopted.

Notable ADA compliant public right-of-way must focus on cross-slope and superelevation, longitudinal grades, ramps and landings, and

surface material design.

Cross-Slope and Superelevation Cross-slope is provided as an important safety feature for users but is also calculated for appropriating drainage of water off the surface to

a drainage system such as a street gutter or ditch. PROWAG states that individuals with disabilities, such as wheeled mobility devices,

generally need less steep slopes to conserve energy and to better maintain control of the wheeled mobility device. NCDOT guidelines

recommends that grades greater than 5% are undesirable. In addition, steep grades affect the safety of all users, particularly where multiple

types of users are on the path at the same time.

Guidelines  Maximum cross slope for the trail is 2%. The preference is to have the trail sloped in one direction. If a center crowned typical

section is needed, the maximum cross slope is 1%.

 AASHTO maximum allowance cross slope for shoulders is 6H:1V.

 Superelevation is not required since it is accounted for with the horizontal curvature. If cross slope does need to transition, the

transition length must be a minimum of 5 feet per one percent of change.

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