17.24.060 Street construction.
A. All streets, including cul-de-sacs, temporary turnarounds and alleys, shall be constructed by the subdivider in accordance with construction standards developed and issued by the city engineer. For purposes of this section, the construction required includes, as a minimum, the driving surfaces, shoulders, ditches, culverts and other surface drainage, and cuts and fills. It also includes curbs, gutters, parkways, sidewalks, boardwalks and other street-related improvements required by the planning commission. Unless the city engineer has issued a more stringent standard, the following apply as the minimum construction standards:
1. The maximum allowable grade of any street is ten (10) percent, except the grade at intersections may not exceed plus or minus one-half (1/2) of one (1) percent for a distance of fifty (50) feet from the edge of the improved driving surface of the intersected street;
2. Minimum drainage grade on all streets and alleys shall be two (2) percent;
3. Embankments shall not be less than a three-to-one slope;
4. All slopes shall be seeded;
5. Within the improved driving surface of a street, there shall be a minimum of six (6) inches of compacted C1 gravel rolled to ninety (90) percent compaction;
6. All local streets shall have a minimum of two (2) fourteen- (14-) foot travel lanes and three- (3-) foot shoulders for a total surface width of thirty-four (34) feet;
7. In areas where on-street parking is deemed appropriate and needed by the planning commission, shoulder width shall be increased to seven (7) feet for a total surface width of forty-two (42) feet;
8. Arterial and collector streets shall have a minimum of two (2) fourteen- (14-) foot travel lanes and four- (4-) foot shoulders for a total surface width of thirty-six (36) feet;
9. The travel lanes of arterial and collector roads shall have an improved surface that meets the city engineer’s specifications and is approved by the public works director;
10. Cul-de-sacs and temporary turnarounds shall have an improved driving surface of at least a sixty- (60-) foot radius plus a two- (2-) foot shoulder. Alleys shall have an improved driving surface for the entire dedicated width of the alley. Additional driving surface width, parking lanes and shoulders proposed by the developer or required by the planning commission shall be constructed under the standards issued by the city engineer;
11. Where construction is required by the planning commission, pedestrian trails, boardwalks and sidewalks shall be constructed to a width of six (6) feet or such greater width as the planning commission may require;
12. All streets, including cul-de-sacs and temporary turnarounds, shall be constructed so as to have a minimum height of thirty-six (36) inches from the ground at any point;
13. Trafficways shall be centered within rights-of-way except where the Alaska Department of Transportation and Public Facilities has offset the trafficway, or when unusual physical circumstances dictate otherwise.
B. All streets shall be designed and built with proper coordination between height and culvert placement to assure that the street is not threatened by runoff from surrounding areas and that the street does not impede water runoff.
C. The construction requirements for arterial and collector streets set out in subsections (A)(8) and (9) of this section apply only:
1. To the part of the arterial or collector that is within the subdivision; and
2. Where the subdivision has direct or close access to the street; and
3. Where the city contributes to the cost of construction in an amount equal to the estimated cost of construction in excess of the estimated cost of constructing the street to local standards.
If conditions of subsections (C)(1) and (C)(2) of this section are met, but the city fails or refuses to meet the requirements of subsection (C)(3) of this section, the subdivider shall construct the street to local street standards. The cost estimates shall be those of the city engineer. [Ord. 01-05 § 7.]