§ 70-6. General requirements and design standards
(a) Streets.
(1) Conformity to major street plan. The width and location of streets shall conform to such major street plan as the city council may have adopted, both as to horizontal and vertical alignment and right-of-way widths.
(2) Relation to adjoining street system. The proposed street system shall extend all existing major streets and such existing secondary and local-access streets as may be desirable for convenience of circulation. Where possible, the width and the horizontal and vertical alignment of extended streets shall be preserved.
(3) Street jogs. Where off-sets in street alignment are, in the opinion of the city council, unavoidable, such off-sets may be employed provided the distance between center lines is not less than 125 feet.
(4) Large-lot subdivisions. If the lots in the proposed subdivision are large enough to suggest re-subdivision in the future, or if part of the tract is not subdivided, consideration must be given to possible future street openings and access to future lots which could result from such re-subdivision.
(5) Through traffic. Local residential streets shall be designed so as to discourage high-speed or through traffic.
(6) Topography. The street system shall bear a logical relationship to the natural topography of the ground.
(7) Street right-of-way widths. Street width and street right-of-way width shall be measured from front lot line to front lot line of opposite lots.
a. Residential streets. Residential streets shall have a minimum right-of-way width of 60 feet. Paving shall be not less than 24 feet in width with three-foot shoulders without curbs or not less than 27 feet with curbs.
b. Collector streets. Collector streets shall have a minimum right-of-way width of 70 feet. Paving shall be not less than 24 feet in width with six-foot shoulders without curbs or not less than 37 feet with curbs.
c. Major thoroughfare. The width of major thoroughfares shall be determined by the city council or the city's master thoroughfare plan; however, this classification carries a minimum right-of-way of 100 feet and a maximum of 120 feet. (04-16)
(8) Street horizontal alignment. The maximum deflection in alignment permitted without use of curve shall not exceed one degree. (04-16)
(9) Major street curves. Curves along street centerlines shall conform to the following standards, with exceptions to these standards granted only by the city council:
Classification Design Speed
(MPH)Centerline Radius
(feet)Desirable Minimum Major 55 1000 800 Secondary 40 550 425 Local 30 300 200 (10) Reverse curves. Reverse curves whenever possible shall be separated by a minimum tangent of 100 feet,
(11) [Vertical curves.] Vertical curves shall be provided for all grade changes greater than one degree (see Appendix 1).
(12) Dead-end streets/culs-de-sac.
a. Turnarounds are to have a minimum right-of-way radius of 60 feet and a pavement radius of 45 feet.
b. Maximum length. The maximum length of a dead-end street with a permanent turnaround or a cul-de-sac with a permanent turnaround shall be 600 feet.
c. Temporary turnaround. A temporary turnaround is to be provided at the end of streets more than 400 feet long that will be extended in the future. The following note should be placed on the plat: Cross-hatched area is temporary easement for turnaround until street is extended [give direction] in a recorded plat.
(13) Street intersections.
a. Angle of intersection. Except where existing conditions will not permit, all streets, major and minor, shall intersect at a 90 degree angle. Variations of more than ten degrees on minor streets and more than five degrees on major or secondary streets must first be approved by the city council.
b. Radius at acute comers. Acute angle intersections approved by the city council are to have 25 foot or greater radii at acute comers.
c. Center-line tie with existing streets. Each new street intersecting with or extending to meet an existing street shall be tied to the existing street on center line with dimensions and bearings to show relationship.
(14) Partial or half-streets. Partial or half-streets may be provided where the city council finds that a street should be located on a property line. The following note shall be used in all such dedications: "This ____________ foot strip is dedicated as easement for all utility purposes including storm and sanitary sewers and shall automatically become dedicated for street purposes when and insofar as a ____________ foot strip adjacent to it is so dedicated and the required improvements are installed."
(15) Reserve strips. Provisional one foot reserves may be used along the side or end of streets that abut acreage tracts, accompanied by a note on the plat that states as follows: "One foot reserve to become automatically dedicated for street purposes when adjacent property is subdivided in a recorded plat."
(16) Street names. New streets shall be named so as to provide continuity of name with existing streets and so as to prevent conflict with identical or similar names in other parts of the city.
(17) Street and alley maintenance. The repair and maintenance of all streets and alleys shall be the responsibility of the abutting property owners or a valid and functioning association of homeowners or property owners within the subdivision. All applications for approval of any preliminary plan or final plat of a proposed residential subdivision in which the construction or placement of any streets or alleys is a component must be accompanied by true and correct copies of homeowner's association regulations or deed restrictions which require all street and alley maintenance to be the responsibility of a homeowner's association or abutting property owners.
(b) Lots.
(1) Use. All lots shown on the plat will be for residential purposes unless otherwise noted. The standards that follow apply to residential lots.
(2) Lot size. The minimum area of all lots shall conform with the city's comprehensive zoning ordinance. The minimum area of all lots shall be at least the size prescribed in the zoning regulations applicable to that district.
(3) Minimum width. Lots with radial side lines diverging toward the rear shall have a minimum of 200 feet width, 75 feet behind the front property line, and lots that have radial side lot lines convergent toward the rear shall have a minimum of 200 feet width, 250 feet behind the front property line.
(4) Minimum depth. No lot shall have a depth of less than 300 feet.
(5) Lots on drainage easements. Minimum usable lot depths for lots backing on natural drainage easements shall not be less than 100 feet measured between front lot line and drainage easement.
(6) Lot width definition. The lot width is the average of front and rear lot dimensions.
(7) Lot shape. Lots should be rectangular insofar as practicable. Sharp angles between lot lines should be avoided. The ratio of depth to width should not ordinarily exceed two and one-half times.
(8) Lot lines. Side lot lines should be perpendicular or radial to street frontage and the following note may be used in lieu of bearings: All side lot lines are either perpendicular or radial to street frontage unless otherwise noted.
(9) Lot facing.
a. Street frontage. Each lot shall be provided with adequate street access.
b. Front facing. In general, an arrangement placing adjacent lots at right angles to each other should be avoided.
(10) Lot numbering. All lots are to be numbered consecutively within each block. Lot numbering may be cumulative throughout the subdivision if the numbering continues from block to block in a uniform manner that has been approved on an overall preliminary plan.
(11) Driveway restrictions. Rear and side driveway access to major thoroughfares shall be prohibited.
(c) Building lines.
(1) Front street. The front building lines shall not be less than 75 feet from the front property line.
(2) Side, rear. The side and rear building line set-backs shall be as set forth in the city's comprehensive zoning ordinance and the zoning regulations applicable to the district in which the property lies.
(d) Alleys.
(1) Alley width. Where provided, alley rights-of-way shall not be less than 20 feet.
(2) Alley intersections. All alleys intersecting with another alley shall have a centerline radius of 40 feet, a property line radius of 30 feet, and shall conform to the standard details.
(3) Dead-end alleys. Dead-end alleys will not be permitted. Alleys in new subdivisions shall connect to alleys in adjacent subdivisions wherever feasible.
(4) Alleys required. Alleys shall be required in all business areas and in those portions of new residential subdivisions where partial blocks are needed to complete existing blocks with alleys.
(e) Easements.
(1) Size. The size of easements for drainage shall be a minimum of 15 feet in width or as established by the city engineer.
(2) Use. Where necessary, easements shall be retained for wires, conduits, storm sewers, sanitary sewers, water lines, open drains, gas lines or other utilities. Such easements may be required across parts of lots (including side lines), other than as described above, if in the opinion of the city council same is needed.
(3) Underground utilities. All subdivisions shall place all utilities underground after the effective date of this chapter.
(4) Major trees within utility easements. Every precaution shall be utilized to protect the natural environment of the subdivision, preserving prominent trees wherever possible, and the owner/subdivider shall advise the city council of the necessity of destroying an inordinate amount of trees, and the method of restoration of the area in keeping with the spirit of the city.