§ 151.133 DESIGN STANDARDS.
   The subdivision of land, including the arrangement, character, extent, width, grade and location of all streets, alleys or other land to be dedicated for public use, shall conform to the General Development Plan and to the Official Map of the city as approved and adopted by the City Council and other responsible governmental bodies; 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.
   (A)   Streets.
      (1)   All streets 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.
      (2)   Where such is not shown in the General Development Plan or on the Official Map, the arrangement of streets in a subdivision shall either:
         (a)   Provide for the continuation or appropriate projection of existing principal streets in surrounding areas; or
         (b)   Conform to a plan for the area of neighborhood approved or adopted by the Plan Commission to meet a particular situation where topographical or other conditions make continuance or conformance to existing streets impracticable.
      (3)   Minor streets shall be so laid out that their use by thru traffic will be discouraged.
      (4)   Where a subdivision abuts or contains an existing or proposed expressway or primary street, as shown on the General Development Plan or on the Official Map, the Plan Commission may require marginal access streets, reverse frontage with screen planting along the rear property line, deep lots with rear service alleys, or such other treatment as may be necessary for adequate protection of residential properties and to afford separation of thru and local traffic.
      (5)   Where a subdivision borders on or contains a railroad or expressway, the Plan Commission may require a street approximately parallel to and on each side of such railroad or expressway, at a distance suitable for the appropriate use of the intervening land, as for park purposes in residential districts or for commercial or industrial purposes in appropriate districts. Such distances shall also be determined with due regard for the requirements of approach grades and future grade separations.
      (6)   Reserve strips controlling access to streets or alleys shall be prohibited.
      (7)   All street intersections and confluences should encourage safe traffic flow.
      (8)   Street jogs with centerline offsets of less than 125 feet shall be avoided.
      (9)   Tangents shall be introduced between reverse curves on all streets (see Table of Minimum Standards).
      (10)   When connecting street lines deflect from each other at any one point by more than ten degrees, they shall be connected by a curve with a radius adequate to insure clear sight distances (see Table of Minimum Standards).
      (11)   Streets shall be laid out so as to intersect as nearly as possible at right angles and no street shall intersect any other street at less than 60 degrees.
      (12)   No fence, wall, hedge or shrub planting which obstructs sight lines at elevations between two and six feet above the roadways shall be placed or permitted to remain on any corner lot within the triangular area formed by the street property lines and a line connecting them at points 25 feet from the intersection of the street lines, or in the case of a rounded property corner from the intersection of the street property lines extended. The same sight line limitations shall apply on any lot within ten feet from the intersection of a street property line with the edge of a driveway or alley pavement. No tree shall be permitted to remain within such distances of such intersections unless the foliage line, is maintained at a sufficient height to prevent obstruction of such sight lines.
      (13)   Street right-of-way widths shall be shown in the General Development Plan and on the Official Map, and where not shown therein shall be as specified in the Table of Minimum Standards.
      (14)   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 Plan Commission finds it will be practicable to require the dedication of the other half when the adjoining property is subdivided, the other half of the street shall be platted within such tract.
      (15)   Dead-end streets (cul-de-sac) designed to be so permanently, shall not be longer than 500 feet from the intersection of the origin through the center of the circle to the end of the right-of-way, and shall be provided at the closed end with a turnaround having an outside pavement diameter of at least 80 feet, and a street property line diameter of at least 20 feet greater than the outside pavement diameter.
      (16)   No street names shall be used which will duplicate or be confused with the names of existing streets. Existing street names shall be projected wherever possible. Street names shall be subject to the approval of the Plan Commission.
      (17)   Street gradients and vertical curves shall be as specified in the Table of Minimum Standards.
      (18)   There shall be sufficient difference in elevation between street grades and adjoining building sites so that streets can serve as open run-off channels auxiliary to the storm sewers or as detention ponds without flooding adjoining building sites.
TABLE OF MINIMUM STANDARDS FOR STREET DESIGN
STREET
RIGHT-OF- WAY WIDTH - NOT LESS THAN
ROADWAY WIDTH - NOT LESS THAN
RADIUS OF HORIZONTAL CURVES, MINIMUM
LENGTH OF VERTICAL CURVES, MINIMUM
TANGENT BETWEEN REVERSE CURVES, MINIMUM
STREET
RIGHT-OF- WAY WIDTH - NOT LESS THAN
ROADWAY WIDTH - NOT LESS THAN
RADIUS OF HORIZONTAL CURVES, MINIMUM
LENGTH OF VERTICAL CURVES, MINIMUM
TANGENT BETWEEN REVERSE CURVES, MINIMUM
Primary
80 ft.
48 ft.
500 ft.
200 ft.
100 ft.
Secondary or Collector
80 ft.
44 ft.
150 ft.
150 ft.
None
Local - for Row Houses and Apartments
60 ft.
36 ft.
150 ft.
100 ft.
None
Local - for Other Residences
60 ft.
30 ft.
150 ft.
100 ft.
None
Cul-de-Sac
60 ft.
30 ft.
150 ft.
100 ft.
None
Marginal Access
60 ft.
24 ft.
150 ft.
100 ft.
None
In Business Districts
80 ft.
56 ft.
150 ft.
100 ft.
None
 
MINIMUM STANDARDS FOR STREET DESIGN
STREET
MAXIMUM GRADIENT
MINIMUM GRADIENT
TANGENT PROPERTY LINES AT STREET INTERSECTIONS
STREET
MAXIMUM GRADIENT
MINIMUM GRADIENT
TANGENT PROPERTY LINES AT STREET INTERSECTIONS
Primary or Major
5%
0.35%
25 ft.
Secondary or Collector
5%
0.35%
20 ft.
Local - For Row Houses and Apartments
6%
0.35%
15 ft.
Local - For Other Residences
6%
0.35%
15 ft.
Cul-de-Sac
6%
0.35%
15 ft.
Marginal Access
6%
0.35%
15 ft.
In Business Districts
2%
0.35%
 
   (B)   Alleys.
      (1)   Alleys shall be provided in commercial, business and industrial districts, except that the Plan Commission may waive this requirement where other definite and assured provisions are made for service access, such as off-street loading, unloading and parking, consistent with and adequate for the uses proposed.
      (2)    Alleys will be required in all new subdivisions, except as deemed necessary and on the recommendation of the Plan Commission.
      (3)   The right-of-way width of an alley shall be 30 feet in residential areas and 40 feet in commercial, business and industrial districts.
      (4)   Alley intersections and sharp changes in alignment shall be avoided, but where necessary corners shall be cut off sufficiently to permit safe vehicular movement.
      (5)   Dead-end alleys shall be avoided where possible, but if unavoidable, shall be provided with adequate turnaround facilities at the deadend, as determined by the Plan Commission.
   (C)   Easements.
      (1)   Easements across lots or centered on rear or side lot lines shall be provided for utilities and/or drainage where necessary and shall be at least 15 feet wide.
      (2)   Where a subdivision is traversed by a water course, drainage way, channel or stream, or other body of water, appropriate dedications or easement provisions, with adequate width or construction to accommodate storm water drainage through and from the subdivision, shall be made. The width of such easement or dedication to accommodate a stream or other flood water run-off channel for operation of maintenance and construction equipment, whichever width is greater. Such easements and/or dedications shall be drawn on the subdivision plat and preserved for drainage.
   (D)   Block standards.
      (1)   The maximum lengths of blocks shall be 1,600 feet. Blocks over 600 feet may require cross-walkways. Cross-walk easements not less than ten feet in width shall be provided where deemed necessary by the Plan Commission at the approximate centers of the blocks. The use of additional cross-walkways in any instance to provide safe and convenient access to schools, parks or other similar destinations will be specified by the Plan Commission or the City Council.
      (2)   No specific rule concerning the shape of blocks is made, but blocks must fit easily into the overall plan of the subdivision and their design must evidence consideration of lot planning, traffic flow and public areas.
      (3)   Blocks intended for commercial and industrial use must be designated as such, and the plan must show adequate off-street areas to provide for parking, loading docks and such other facilities that may be required to accommodate motor vehicles.
   (E)   Lot standards. All residential lots shall conform to the minimum requirements of this zoning code.
   (F)   Parks, schools and public areas.
      (1)   Where a proposed park, playground, school or other public use area shown on the General Development Plan or on the Official Map for the city and adjacent unincorporated areas, is located in whole or in part in a subdivision, the Plan Commission or the City Council shall require the reservation of such area for acquisition in whole or in part within the subdivision in those cases where the Plan Commission and the City Council deem such requirements to be reasonable. However, in no case shall the total amount of required public areas which are to be dedicated or reserved for acquisition by the proper governing authorities exceed 7% of the total gross acreage controlled by one developer. Such dedication or reservation shall be in addition to any public street dedications. The acquisition of the additional area needed for parks, playgrounds, schools or other public use other than streets and alleys, shall be secured by the proper governing body or arrangements made for securing the area from the owner within a period not to exceed one year.
      (2)   In subdividing any land within the city due regard shall be shown for all natural features such as tree growth, water courses, historic spots or similar conditions which, if preserved, will add attractiveness and value to the proposed development.
(Ord. 88-30, passed 8-8-88 ; Am. Ord. 95-40, passed 9-11-95) Penalty, see § 151.999