13-10-002

Division 13-10-002
Street Design

Sections:

Street design shall:

A. Provide for appropriate continuation of existing and proposed arterial and collector streets and bikeways in accordance with the most recently adopted version of the Regional Plan and Division 13-10-014.

B. Provide sufficient rights-of-way for local service or a frontage street along major highways, or other treatment by separation to protect residential properties along arterial and collector streets.

C. Correlate with the drainage facilities when streets are used for on-site local drainage.

D. Be designed so that through traffic in residential districts is carried on arterial and collector streets. Residential subdivisions shall be designed so that the local streets provide vehicular, bicycle, and pedestrian access to the residences and services of the homes fronting the streets. Table 13-10-011-01 identifies the application of the different street cross sections, which are based on the total traffic volumes of the street.

1. In order to provide neighborhoods that are safe, functional, and express an atmosphere of community, subdivisions should be designed so that the local streets carry volumes no greater than five hundred (500) ADT. When the traffic volumes on a given street exceed five hundred (500) ADT, it should only provide access to a local street and not to residential properties. In those instances, the typical street section used shall be a minor collector as follows: The section will exclude the center left turn lane (left turn lanes will be required as needed where the minor collector intersects another collector or arterial street).

E. Require that new designs incorporate traffic calming techniques into all new residential streets. The goal is to reduce residential traffic speeds to within the design speed limits, while maintaining safe and reasonable access for all intended normal traffic. In order to achieve this objective, the maximum length of a roadway section between speed control points shall be six hundred sixty (660) feet. A speed control point is defined as any one (1) of the following:

1. Any design condition that requires a complete stop such as the intersection of a local residential street with a collector or arterial street, or a "T" intersection between local streets. (Note: Stop sign control at the intersection between local streets does not qualify.)

2. A horizontal curve that does not exceed a radius of three hundred (300) feet and a corresponding delta of thirty (30) degrees minimum.

In the event that there are circumstances where it is not practical to achieve traffic calming measures with design features as stated above, Table 13-10-011-02 is intended to provide the design engineer with a list of alternative traffic calming design features (listed in order of preference).

See Design Criteria, Table 13-10-011-01, for the design overview.

F. LID Integrated Management Practices (IMPs) as detailed in the City’s LID Guidance Manual as adopted as part of the City of Flagstaff Stormwater Management Design Manual may be allowed in the right-of-way on a case-by-case basis as approved by the City Engineer and Public Works section head.

Only stormwater generated in the public right-of-way will be allowed to be associated with an IMP. No stormwater generated on private property will be allowed to be associated with an IMP in the right-of-way.

LID IMPs, if allowed in the public right-of-way, shall be considered private drainage infrastructure. Ownership and maintenance responsibilities for LID IMPs shall be as described in the amendments to the Floodplain Management Regulations. (Ord. 2017-22, Rep&ReEn, 07/05/2017)

13-10-002-0001 Street Design