PRSR 10-12-1994 - Laserfiche WebLink

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Feb. 8, 1983 BIKEWAYS _22_ H. CLEAR ZONE (distance from bikeway to traveled way) (ROADS WITHOUT CURBS) For on-road bikeways refer to the bikeway design tables to assess the road suitability for bicycle travel. $ 20'MIN. TRAVELED The tables will also enable "pretesting"of shoulder widen- Riw t MIN WAY ing and surfacing. Bike traffic must flow the same direction z'MIN. as adjacent motor vehicle traffic. Two-way bike traffic on 2' MIN. one-side of the road is not permitted. PAVED BIKEWAY For off-road bikeways, there are two categories: roads without curbs and roads with curbs. The proper set back from the traveled way is an important consideration for the designer because operation of the facility is de- (ROADS WITH CURBS)* pendent upon adequate separation from each respective B' STREET travel mode (motor vehicle, bike, pedestrian) and sta- MIN. tionary objects(poles, signs. . .).See Figure G. 4' MIN. I. DRAINAGE • `= PAVED BIKEWAY For bike routes and lanes the existing roadway drain- age is normally adequate. However, on curb and gutter 'PROVIDES ROOM FOR SIGNS,POLES,ETC. sections a check of ponding depths should be made and corrective action proposed if depths are significant. This may entail improved grate designs or wider bike lanes. FIGURE G On off-road bikeways, the surface of the bikeway • should have a cross-slope of two percent for the proper drainage. Sloping in one direction usually simplifies longi- tudinal drainage design and surface construction, and accordingly, is the preferred practice. Ordinarily, surface drainage from the path will be adequately dissipated as it flows down gently sloping terrain. However, when the bikeway is constructed on the side of a hill, a drainage ditch of suitable dimensions may be necessary on the uphill side to intercept the hillside drainage. See Figure H. Cul- verts or bridges are necessary where a bikeway crosses a 2% drainage channel. Sizing of the required waterway opening - --- should be determined by a hydraulics engineer. Minimum ///A\\\ culvert size used for bikeway drainage should be 18 inch . diameter. Bikeway Drainage inlet grates on bikeways shall have openings narrow enough and short enough to assure bicycle tires will not drop into the grates regardless of the direction of bicycle travel. Where it is not immediately feasible to re- place existing grates with standard grates designed for 2_%_ bicycles, 1 inch x 1/4 inch steel cross straps should be welded to the grates at a spacing of 6 inches to 8 inches Variable on center, to reduce the size of the openings. See Standard Plates 4151 and 4152 for acceptable designs of grates. Bikeway • FIGURE H