(a) Conformity to City Standards. The arrangement, character, extent, width and location of all streets shall conform to the City's "Thoroughfare and Green Space" and the requirements set forth herein, unless specific requirements are waived by the City Planning Commission. The design of proposed streets and public access to adjacent unplatted lands shall be arranged so that the entire area can be served with a coordinated public street system. All streets must be built to City standards.
(b) Classifications.
(1) Major arterial thoroughfares shall be planned for the continuation of movement of fast traffic, generally over forty-five miles per hour, between points of heavy traffic generation and from one section of the community to another. They shall contain as few intersections with minor streets as possible.
(2) Minor arterial thoroughfares are similar in nature to major arterials, but are for lower volumes and speeds, generally thirty-five to fortyfive miles per hour.
(3) Collector streets shall provide a traffic route from local. streets to arterial thoroughfares. Collector streets normally contain a relatively large number of intersections with local streets and few intersections with arterial thoroughfares.
(4) Local streets shall provide direct and full access to each lot and shall be laid out so that their use by through traffic will be discouraged. The street system shall be designed so that all proposed streets shall be in conformity with modern practices of land subdivision and in general conformity with a plan for the most advantageous development of the entire neighborhood. The streets shall be extended to the boundaries of the tract to be recorded and aligned with existing streets, unless prevented by topography or other physical conditions or unless, in the opinion of the Planning Commission, such extension is not necessary or desirable for the coordination of the layout of the subdivision with the development of adjacent tracts. Dead-end streets or cul-de-sacs will be approved only when necessitated by topography or other physical conditions or where, in the opinion of the Planning Commission, they are appropriate for the type of development contemplated.
(5) Industrial streets are those streets within industrial zoning districts which will be subject to a large percentage of heavy truck traffic. In general, they will be streets within industrial parks, but other streets having a high or potentially high truck volume may also be classified as industrial streets.
(c) Street Right-of-Way and Pavement Widths. Street right-of-way and pavement widths shall be as follows:
Right-of-Way Pavement
Classification Width (ft.) Width (ft.)
Classification Width (ft.) Width (ft.)
Major 80 64
Minor 80 54
Industrial 60 40
Collector 60 40
Local
over 500 ft. in length 50 32
Up to 500 ft. in length 50 28
Pavement width is measured from back-of-curb to back-of-curb.
(d) Half Streets. Half streets shall be prohibited, except where there is an existing half street adjacent to the subdivision, in which case the remaining half of the street shall be platted.
(e) Cul-de-Sac and Dead-End Streets.
(1) A. street designed to be a permanent cul-de-sac should not be longer than 800 feet and shall be provided at the closed end with a turnaround having an outside pavement diameter of at least eighty feet and a street right-of-way line diameter of at least 100 feet.
(2) If the subdivision creates a temporary dead-end street that is intended to be extended in the future, an eighty-foot diameter turn-around shall be constructed of six inches of 304 compacted base material. Such. turn-around shall be within an easement granted to the City by the developer and shall be maintained to the satisfaction of the City Engineer. Such easement shall be automatically vacated to the abutted property owners when the dead-end street is legally extended and an additional right-of-way dedicated to the City. If such dead-end street is not legally extended within five years of approval of the final plat that created it, the developer must construct a turn-around as required for a permanent cul-de-sac (including curb and gutter) and dedicate the required 100-foot right-of-way to public use. If such dead-end street extends only the depth of the corner lot past a street intersection, no turn-around will be required.
(f) Grades. It is recognized that the maximum grade must vary with the severity of the natural terrain. Thus, the following maximum grades are set:
(1) Level terrain: four percent maximum grade
(2) Rolling terrain: eight percent maximum grade
(3) Hilly terrain: fifteen percent maximum grade An absolute minimum grade of 0.5 percent is required.
(g) Changes in Grades. All changes in street grades in excess of one percent shall be connected by vertical curves. The minimum length of a vertical curve shall be twenty tunes the algebraic difference in the rate of grade for major, minor or industrial streets and fifteen times the algebraic difference in the rate of grade for collector or local streets. Grade changes (with or without a vertical curve) shall be no closer than 300 feet.
(h) Minimum Centerline Radii. The minimum centerline radius for horizontal curves shall be 400 feet for major, minor or industrial streets and 100 feet for collector or local streets.
(i) Reverse Horizontal Curves. Major, minor, and industrial streets shall have a minimum 100-foot tangent section between reverse horizontal curves. No minimum tangent section is required for collector or local streets.
(j) Intersections.
(1) Intersections shall be no closer than 125 feet on local or collector streets and no closer than 250 feet on major, minor or industrial streets. The highest level (most restrictive) street involved governs.
(2) Curbs at intersections shall be rounded, using the following minimum radii:
A. Major - 50
B. Minor - 45
C. Industrial - 50
D. Collector - 30
E. Local - 30
(3) The minimums set forth in paragraph (j)(2) hereof shall increase to the following when the minimum angle of intersection is between sixty and seventy-five degrees:
A. Major - 55
B. Minor - 55
C. Industrial - 60
D. Collector - 45
E. Local - 40
(4) Intersections with an angle less than sixty degrees will not be permitted.
(Ord. 93-fit. Passed 10-3-94.)