§ 154.36 STREETS AND ALLEYS.
   (A)   The arrangement of thoroughfares and collector streets shall conform as nearly as possible to the City Comprehensive Plan.
      (1)   Except for cul-de-sacs, streets normally shall connect with streets already dedicated in adjoining or adjacent subdivisions, or provide for future connections to adjoining unsubdivided tracts, or shall be a reasonable projection of streets in the nearest subdivided tracts.
      (2)   The arrangement of thoroughfares and collector streets shall be considered in their relation to the reasonable circulation of traffic, to topographic conditions, to run-off storm water, to public convenience and safety, and in their appropriate relation to the proposed use of the area to be served.
   (B)   Minor streets should be so planned as to discourage their use by non-local traffic. Dead-end streets are prohibited, but cul-de-sacs will be permitted where topography or other conditions justify their use. Cul-de-sacs shall normally not be longer than 500 feet, including a terminal turn-around which shall be provided at the closed end, with a right-of-way radius of not less than 70 feet.
   (C)   Where the plat to be submitted includes only part of the tract owned or intended for development by the subdivider, a tentative plan of a proposed future street system for the unsubdivided portion shall be prepared and submitted by the subdivider.
   (D)   When a tract is subdivided into larger than normal building lots or parcels, the lots or parcels shall be so arranged as to permit the logical location and openings of future streets and appropriate resubdivision, with provision for adequate utility connection for the resubdivision.
   (E)   Under normal conditions, streets shall be laid out so as to intersect as nearly as possible at right angles, except where topography or other conditions justify variations. The minimum angle of intersection of streets shall be 80 degrees. Street intersection jogs with an offset of less than 125 feet shall be avoided.
   (F)   Wherever the proposed subdivision contains or is adjacent to the right-of-way of a limited access, U.S. or state highway or thoroughfare, provision may be made for a marginal access street approximately parallel and adjacent to the boundary of the right-of-way, or for a street at a distance suitable for the appropriate use of land between the street and right-of-way. The distance shall be determined with due consideration of the minimum distance required for approach connections to future grade separations, grade crossing or for lot depths.
   (G)   Alleys shall be provided in commercial and industrial districts, except that this requirement may be waived where other definite and assured provision is made for service access, such as off-street loading, unloading and parking consistent with and adequate for the uses proposed.
      (1)   Except where justified by special conditions, such as the continuation of an existing alley in the same block, alleys will not be approved in residential districts.
      (2)   Alleys, where provided, shall not be less than 16 feet wide for residential alleys and not less than 25 feet for commercial and industrial alleys.
      (3)   Dead-end alleys shall not be permitted, except that this requirement may be waived where an adequate turn-around is provided.
   (H)   Dedication of half streets will not be approved, except where it is essential to the reasonable development of the subdivisions and in conformity with the other requirements of these regulations, where it is found that it will be practical to require the dedication of the other half when the adjoining property is subdivided, or where it becomes necessary to acquire the remaining half by condemnation so it may be improved in the public interest.
   (I)   For all public ways hereafter dedicated and accepted, the minimum right-of-way widths for streets and thoroughfares shall be as shown in the Comprehensive Plan for the city, and where not shown therein, the minimum rights of way width for streets, thoroughfares, alleys or pedestrian ways included in any subdivision shall not be less than the minimum dimensions for each classification as follows:
Thoroughfare
66 feet
Collector street
60 feet
Minor street
60 feet
Marginal access street
50 feet
Residential alley
16 feet
Industrial commercial alley
25 feet
Pedestrian way
10 feet
Where existing or anticipated traffic on thoroughfares warrants greater widths of right-of-way, these shall be required.
 
      (1)   Street grades: the grades in all streets, thoroughfares, collector streets, minor streets and alleys in any subdivision shall not be greater than the maximum grades for each classification as follows:
 
Thoroughfare
4%
Collector street
5%
Minor street
8%
Alley
8%
Any grades greater than the aforementioned shall be subject to review by the Community Development Officer.
In addition, there shall be a minimum grade on all streets and thoroughfares of not less than five-tenths of 1%.
 
      (2)   Street alignment: the horizontal and vertical alignment standards on all streets shall be as follows:
         (a)   Horizontal; radii of center line:
 
Thoroughfare
500 feet minimum
Collector street
400 feet minimum
Minor street
150 feet minimum
There shall be a tangent between all reversed curves of a length in relation to the radii of the curves so as to provide for a smooth flow of traffic.
 
         (b)   Vertical; all changes in street grades shall be connected by vertical parabolic curves of a length as follows:
 
Thoroughfare
30 times the algebraic difference in the percentage of grade of the two adjacent slopes
Collector street or minor street
20 times the algebraic difference in the percentage of grade of the two adjacent slopes
 
      (3)   All proposed streets shall be offered for dedication as public streets. No private streets shall be permitted, except as set forth in other ordinances.
(Prior Code, § 4-901)