|For Off-Road Shared Use Path Design, the following shall apply:|
|Minimum Surface Width (two-way)||8 ft (a)|
|Shoulder/Clear Zone||2 ft (b) (c)|
|Inslope||Maximum 1:2 (rise:run)|
|Design Speed||20 mph (d)|
|Vertical Clearance over lane and shoulder||10 ft nominal (8 ft nominal if passage of emergency or maintenance vehicles is not required) (e)|
(a) Ten feet is desired for a shared use path. Five feet is required for a one-way shared use path.
(b) For vehicular roadway bridges or underpasses accommodating an off-road bicycle path or shared use path, the total width (minimum surface width plus shoulder/clear zone) is eight feet minimum, with ten feet being desirable. However, whenever practicable, the shoulder/clear zone of an off-road bike or shared use path should be carried across or under a vehicular bridge. When the clear zone of an off-road bike or shared use path cannot practicably be carried across or under the bridge, a lead-in guardrail must be provided, unless the surface width of the approach path is narrowed at a maximum 1:50 taper while providing the minimum travel lane and shoulder/clear zone widths through the structure.
For a separate off-road bicycle path or shared use path, the shoulder/clear zone must be carried across bridge or underpass structures. Minimum structure clear width must be 12 feet. When the surface width plus shoulder/clear zone width of the approaching off-road bike or shared use path is greater than the proposed clear width of the structure, then a lead-in bicycle safety railing is required, unless the surface width of the approach path is narrowed at a maximum 1:50 taper while providing the minimum travel lane and shoulder/clear zone widths through the structure.
(c) Clear zone is measured from the edge of the travel lane.
(d) Use a 30 mph design speed for grades longer than 500 feet and greater than four percent, from the uphill point where the grade equals four percent to 500 feet beyond the downhill point where the grade becomes less than four percent. The maximum allowable grade is 8.3 percent.
(e) When an off-road bicycle or shared use path continues through a box culvert structure, up to three inches of bituminous surfacing may be used through the structure. The minimum vertical clearance for box culvert structures is nine feet, nine inches, or seven feet, nine inches if passage of emergency or maintenance vehicles is not necessary.
20 SR 1041; 23 SR 1455; 24 SR 1885; 29 SR 449; 32 SR 608; 36 SR 925; 42 SR 485
November 20, 2017