Chapter 6
SUBDIVISION DESIGN STANDARDSlinklink

http://sterlingcodifiers.com/codebook/index.php?book_id=&chapter_id=29140
12-6-1: CONFORMITY WITH COMPREHENSIVE PLAN ELEMENTS:
12-6-2: STREETS:
12-6-3: ALLEYS:
12-6-4: EASEMENTS:
12-6-5: BLOCKS:
12-6-6: LOTS:

12-6-1: CONFORMITY WITH COMPREHENSIVE PLAN ELEMENTS:linklink


The proposed subdivision shall conform to each element contained in the comprehensive plan. (Ord. 98-25, 9-1-1998)
http://sterlingcodifiers.com/codebook/index.php?book_id=&chapter_id=29140#s1015844
12-6-2: STREETS:linklink


A. Conformity: The arrangement, character, extent, width, grade and location of all streets shall conform to the city's most current approved comprehensive plan and approved transportation plan and shall be considered in their relation to existing and planned streets, to topographical conditions, to public convenience and safety, and in their appropriate relation to the proposed uses of the land to be served by such streets, where not shown on the transportation plan map, the arrangement and other design standards of streets shall conform to the provisions found herein.


B. Relation To Adjoining Street System: The arrangement of streets in a new subdivision shall make provision for the continuation of the existing streets in adjoining areas.


C. Projection Of Streets: Where adjoining areas are not subdivided, the arrangement of streets in a new subdivision shall make provisions for the proper projection of streets.


D. Streets Carried To Property Lines: When a new subdivision adjoins an undeveloped parcel of land susceptible of being subdivided, then the new streets shall be carried to the boundaries of the tract proposed to be subdivided.


E. Street Jogs Prohibited: Street jogs at intersections with centerline offsets of less than one hundred feet (100') shall be avoided.


F. Dead End Street Or Cul-De-Sac: Dead end streets or cul-de-sacs designed to be so permanently, shall not be longer than six hundred feet (600') in length, and shall be provided at the closed end with a turnaround having an outside roadway diameter of at least eighty feet (80'), and a street property line diameter of at least one hundred feet (100'). If a dead end street is of a temporary nature, a similar turnaround shall be provided and provisions made for future extension of the street into adjoining properties. If the cul-de-sac is less than one hundred fifty feet (150') in length, the turnaround may be omitted. Each turnaround may have a center island of not less than twenty feet (20') in diameter. Each island shall be approved with the final plat. Approved islands will be curbed, and if unpaved, any plantings shall not interfere with sight clearance.


G. Arterial Streets: Where a subdivision abuts or contains within its boundaries an arterial street which has not been improved to the design standards specified in the city's most current transportation plan, an accel-decel turning lane shall be provided where any street within the subdivision intersects the arterial street to afford separation of through and local traffic. This requirement shall not apply to private residential drives.


H. Local Or Minor Streets: Local streets shall be so laid out that their use by through traffic will be discouraged.


I. Street Right Of Way Widths:

1. Street widths shall not be less than as follows:

Street Type   Width (Feet)  
   
Arterial   120  
Collector   80  
Residential collector   60  
Local, apartments   60  
Local, all others   50  
Cul-de-sac   50  
Frontage or marginal access   40  

2. In front of areas designated and zoned for commercial use, or where a petition for a change in zoning is contemplated to permit such use, the street width shall be increased by such amount on each side as may be deemed necessary by the planning commission to assure the free flow of through traffic without interference by parked vehicles and to provide safe parking space for such commercial district.


J. Intersections: The intersections of more than two (2) streets at one point shall be avoided, except where it is impracticable to secure a proper street system otherwise. Streets shall intersect one another at an angle as near to a right angle as possible, and no intersections of streets at angles less than sixty degrees (60°) shall be approved. Street intersections shall be rounded with a radius of twenty five feet (25') measured at the face of curbs when the said intersection occurs at right angles. If an intersection occurs at an angle other than a right angle, it shall be rounded with a curve of a radius acceptable to the planning commission. In commercial or industrial zoning districts, the planning commission may permit comparable cutoffs or chords.


K. Street Deflections: When connecting street lines which connect between intersections deflect from each other, they shall be connected by a curve with a radius adequate to ensure a sight distance of not less than two hundred feet (200').


L. Reverse Curves: A tangent shall be introduced between reverse curves on arterial and collector streets sufficient to provide for the smooth flow of traffic.


M. Subdivision Into Tracts Larger Than Ordinary Building Lots: Where a tract is subdivided into larger parcels than are ordinarily permitted, such parcels shall be arranged so as to allow the opening of future streets and logical further resubdivision.


N. Reserve Strips: Reserve strips controlling access to streets shall be prohibited, except under conditions approved by the planning commission and when such strips are owned by the city.


O. Ingress And Egress: Ingress and egress to residential property shall not be provided on arterial streets.


P. Street Grades: No street grade shall be less than three-tenths of one percent (0.3%), and shall not exceed eight percent (8%) or eleven percent (11%) on local streets, with due allowance for reasonable vertical curves.


Q. Railroad Or Highway Abutting Subdivision: Where a subdivision borders on or contains a railroad right of way or limited access highway right of way, the planning commission may require a street approximately parallel to, and on each side of, such right of way, at a distance suitable for the appropriate use of the intervening land, or for park purposes in residential districts, or for commercial or industrial purposes in appropriate districts. Such distance shall also be determined with due regard for the requirements of approach grades and future grade separations.


R. Half Streets Prohibited: Half streets shall be prohibited, except where essential to the reasonable development of the subdivision in conformity with the other requirements of these regulations and where the planning commission finds it will be practicable to require the dedication of the other half when the adjoining property is subdivided. Wherever a half street is adjacent to a tract to be subdivided, the other half of the street shall be platted within such tract.


S. Street Names And Numbers: Names of new streets shall not duplicate existing or platted street names unless a new street is a continuation of, or in alignment with, the existing or platted street. All street names shall be subject to approval by the planning commission. So far as practicable, street names shall be grouped in categories and names within a category shall be used in only one area of the city; streets which continue in a straight line shall continue with the same name; streets which curve to the extent that they intersect with other parallel streets shall have a separate name for that portion of the street. House numbers shall be assigned by the code administration department of the city.


T. Access To Streets Across Ditches: The subdivider shall provide access to all proposed streets, across all ditches, in a standard method approved by the director of engineering services.


U. Vacation Of Streets: The Metropolitan area planning commission shall not recommend the vacation of any street or part of a street dedicated for public use, if such vacation interferes with the uniformity of the existing street pattern or any future street plan prepared for the area.


V. Private Streets: Public improvements shall not be approved for any private street or drive, unless expressly recommended for approval by the Metropolitan area planning commission.


W. Hardship To Owners Of Adjoining Property Avoided: The street arrangement shall not be such as to cause hardship to owners of adjoining property in platting their own land and providing convenient access to it.


X. Street Interval: In general, provisions should be made for through streets at intervals not exceeding one-half (1/2) mile along arterial streets.


Y. Sidewalks: Sidewalks shall be required pursuant to section 10-6-1 of this code and shall comply with section 12-8-7 of this title. (Ord. 2014-37, 11-18-2014)

http://sterlingcodifiers.com/codebook/index.php?book_id=&chapter_id=29140#s1015845
12-6-3: ALLEYS:linklink


A. Residential Area: Alleys shall not be provided in residential areas, unless expressly approved by the planning commission.


B. Commercial And Industrial Districts: Alleys shall be provided in commercial and industrial districts, except that the planning commission may waive this requirement 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.


C. Width: The minimum right of way width of an alley shall be twenty four feet (24').


D. Dead End: Dead end alleys shall not be permitted, except the planning commission may waive this requirement where such dead end alley is unavoidable and where adequate turnaround facilities have been provided. (Ord. 98-25, 9-1-1998)

http://sterlingcodifiers.com/codebook/index.php?book_id=&chapter_id=29140#s1015846
12-6-4: EASEMENTS:linklink


A. Utilities: Easements with a right of way width of ten feet (10') shall be provided on each side of all rear lot lines and along certain side lot lines where necessary for utilities. When restricted to one side of such line, the easement shall be not less than twenty feet (20') in width.


B. Drainage: Where a subdivision is traversed by a watercourse, drainageway, channel, or stream, there shall be provided a stormwater easement or drainage right of way conforming substantially with the lines of such watercourse, and such further width or construction, or both, as will be adequate for the purpose of protecting private property from flood hazards. Stormwater easements or drainage right of way shall be sufficient to include all flooded area, shall provide ingress and egress together with adequate working room for power driven maintenance equipment. (Ord. 98-25, 9-1-1998)

http://sterlingcodifiers.com/codebook/index.php?book_id=&chapter_id=29140#s1015847
12-6-5: BLOCKS:linklink


A. Factors Governing Dimensions: Block length and width or acreage within bounding roads shall be such as to accommodate the size of lot required by the zoning ordinance and to provide for convenient access, circulation, control and safety of street traffic.


B. Lengths: Block lengths shall not exceed one thousand three hundred twenty feet (1,320'), or be less than two hundred fifty feet (250').


C. Arrangement: A block shall normally be so designed as to provide two (2) tiers of lots.


D. Pedestrian Walkways: In blocks over six hundred feet (600') long, pedestrian crosswalks may be required by the planning commission in locations deemed necessary to public health, convenience and necessity. Such crosswalk shall be ten feet (10') wide and be straight from street to street.


E. Sidewalks And Curb Ramps: Where sidewalks are provided the blocks must be designed to accommodate sidewalks and curb ramps with detectable warnings consistent with section 12-8-7 of this title. (Ord. 2009-09, 4-7-2009)

http://sterlingcodifiers.com/codebook/index.php?book_id=&chapter_id=29140#s1015848
12-6-6: LOTS:linklink


A. Dimensions: Lot dimensions and area shall not be less than the requirements of the city zoning ordinance.


B. Location: All lots shall abut their full frontage on a publicly dedicated street or a street that has received the legal status as such.


C. Corner Lots: Corner lots for residential use shall have extra width to permit appropriate building setback from, and orientation to, both streets.


D. Uninhabitable Lots: Lots subject to flooding and lots deemed by the planning commission to be uninhabitable shall not be platted for residential occupancy, nor for such other uses as may increase danger to health, life or property or aggravate the flood hazard, but such land within the plat shall be set aside for such uses as shall not be endangered by periodic or occasional inundation.


E. Lot Remnants: All remnants of lots below minimum size left over after subdividing of larger tracts must be added to adjacent lots, rather than allowed to remain as unusable parcels.


F. Space For Public Use: Where a proposed park, playground, school or other public use designated on the comprehensive plan is located in whole or in part within a subdivision, the subdivider shall reserve adequate space for such purpose in such area within the subdivision when the planning commission finds the requirement to be reasonably necessary to the public health and welfare of the residents of the subdivision. (Ord. 98-25, 9-1-1998)

http://sterlingcodifiers.com/codebook/index.php?book_id=&chapter_id=29140#s1015849