Low impact A public or private street providing primary access in steep slope and/or ridge top areas. In addition, a low impact street may be identified as a street that is designed and constructed to minimize stormwater runoff through surface treatment and infiltration (using swales and other type of filtering and retention) or designed and constructed as access for minor subdivisions of less than 15 single family homes.
Alley A public or private way providing secondary or service access to abutting property. All new alleys are to be privately-maintained with measures to ensure the travelway is not obstructed in any manner, including byparking.Local - A public or private street providing primary access to a limited number of abutting properties.
Collector A public or private street “collecting” traffic from local streets and carrying it to arterial streets while providing primary access to abutting properties.
Arterial A public street carrying large volumes of through traffic while providing primary access to abutting properties, which are typically developed with commercial, industrial, or multifamily residential uses.
3C.02a Extension to Property Line
All streets shall be extended to the property lines across the property tobe developed, unless the street to be constructed has been approved by the City as a cul-de-sac or other street with no outlet. Where existing rights-of-way abut property to be developed, streets shall be built to connect to rights-of-way as feasible. Future connections terminating at property line shall be signed according to the Manual on Uniform Traffic Control Devices (MUTCD). In locations where these extensions are to be constructed in the future, a cul-de-sac must be provided in accordance with the “Cul-de-Sac Street” portion in this chapter of this section. Other types of turn around may be approved by the City Engineer or his/her designee, provided they comply with current International Fire Code.
3C.03a Minimum Horizontal Curve
Street curvatures shall meet the minimum specifications shown in“Table 3-2: Minimum Horizontal Street Curve Specifications”.
3C.04a Minimum Street Grade
All street grades shall equal or exceed the minimum street grade of 0.5percent.
3C.04b Maximum Street Grade
Street grades typically shall not exceed the maximum street grades shownin “Table 3-3: Maximum Street Grades”.
3C.04c Design Controls for Vertical Curves
Design control for crest and sag vertical curves should conform to the standards established in the most current edition of A Policy on Geometric Design of Highways and Streets published by the AASHTO. The subject standards are based on the formula L = KA where L = length of vertical curve in feet, K = rate of vertical curvature in feet per percent of A, and A = algebraic difference in grades in percent. The City of Asheville will accept the K values used by the North Carolina Department of Transportation (NCDOT) for local and collector types streets shown in Table 3-4 Vertical CurveDesign Control.
3C.05 Left Turn Lanes
3C.05a Storage Length. Left turn lane storage length shall be determined based on an acceptable method approved by the City Engineer or his/her designee.
3C.05b Deceleration Length. On arterial streets, the turn lane length shall provide for deceleration in addition to storage. The minimum taper length shall be 50 feet and shall be considered part of the deceleration length.
3C.05c Tapers may be used as necessary to shift lanes laterally. Refer to “Section 6 - Public Safety” of this manual for Traffic Calming requirements. The minimum taper length is determined by the following “Table 3-5:Minimum Taper Length Equation”.
3C.06 Intersections & Street Spacing
3C.06a Angles. All streets should intersect at right angles. At no time shall a street intersect any other street at less than 75 degrees. Street intersections less than 90 degrees will be reviewed and approved on a case by case basis.
3C.06b Minimum Street Spacing. Spacing between street centerlines shall equal or exceed the minimum distances shown in “Table 3-6: Minimum Street Spacing”.
3C.06c Corner Radii. The street corner radii at intersections shall have radii specifications range as shown in “Table 3-7: Intersection Radii”. Larger corner radii may be used for streets serving primarily industrial uses. Property Line Triangles must be provided at intersections as shown on “Table 3-8: Minimum Intersection Property Line Triangle”.
3F Parking and Loading
Use this form for Commerical or Multi-Family projects only. If you need to request a residential driveway modification, click here for the correct form.
3H.05b Meander. A sidewalk may be constructed so as to provide a gradual meander and to facilitate the installation of landscape material or to avoid obstacles such as fire hydrants or utility poles. The design of the sidewalk shall be such that the safety and usability of the sidewalk is not affected. In no case shall the taper of the sidewalk with respect to the street exceed 5:1, nor shall the distance of the sidewalk from the street exceed 20 feet.
3H.05c Vertical Grade. The vertical grade of a sidewalk shall not exceed five (5) percent, a ratio of 20 feet horizontal to 1 foot vertical (20:1), unless the grade of the adjoining street exceeds this amount. In this case, at no point will the grade of the sidewalk be permitted to exceed the grade of the adjacent street.
3H.05d Cross Slope. The cross slope of the walkway of a pedestrian access route shall be 2 percent maximum.
3H.05h Materials, Thickness, Joints, and Finish. All sidewalks and curbing shall be constructed of 4,000 psi concrete in accordance with “Standard Detail 3.16: Standard Concrete Sidewalk”. In certain districts other materials may be required in accordance with City codes. Materials not meeting ADA requirements are not allowed. The minimum concrete thickness of a sidewalk shall be four (4) inches. At locations where a driveway crosses a sidewalk, a six (6) inch concrete thickness is required. A 1/2 inch expansion joint filled with joint filler and sealer shall be placed between all rigid objects and placed no farther than 50 feet apart for sidewalks extending the full depth of the concrete with the top of the filler 1/2 inch below the finished surface. Joint filler shall be a material conforming to the most current NCDOT Standard Specifications for Road Structures manual. Tool joints shall be spaced to match the width of the sidewalk but be no less than five (5) feet apart. Tool jointsshall be 3/4 inch deep and must not be sealed. The sidewalk surface shall have a broom finish in a transverse direction to pedestrian traffic.