(A) General Requirements.
(1) Frontage on Improved Streets. No subdivision shall be approved unless the area to be subdivided shall have frontage on and access from an existing street on the Official Map, or if there is not an Official Map, unless such a street is an existing state, county, or township highway; or
(a) A street shown upon a plat approved by the Commission and recorded in the office of the County Recorder of Deeds. Such street or highway must be suitably improved as required by the highway rules, regulation specifications, or orders, or be secured by a performance bond required under these regulations, with the width and right-of-way required by these regulations or as indicated on the Official Map or Thoroughfare Plan. Whenever the area to be subdivided is to use an existing street frontage, such street shall be suitably improved as provided herein above.
(b) Whenever a subdivision of more than five lots along a state or county road is developed the Commission may require a turn lane or access road to be constructed to minimize the risk or traffic hazard.
(B) Grading and Improvement Plan. Streets shall be graded and improved and conform to the city construction standards and specifications and shall be approved as to design and specifications by the County Engineer, in accordance with the construction plans required to be submitted prior to secondary approval.
(C) Topography and Arrangement.
(1) Streets shall be related appropriately to the topography. All streets shall be arranged so as to obtain as many as possible of the building sites at, or above, the grades of the streets. Grades of streets shall conform as closely as possible to the original topography. A combination of steep grades and sharp curves shall be avoided. Specific standards are contained in the design standards of these regulations.
(2) All streets shall be properly integrated with the existing and proposed system of thoroughfares and dedicated rights-of-way as established on the Official Map or Thoroughfare Plan, and/or Comprehensive Plan.
(a) Widths of streets and highways shall conform to the width specified by the City Street Superintendent standards cross-section.
(b) All cul-de-sacs shall terminate in a circular right-of-way with a minimum diameter of 100 feet and shall not exceed 600 feet in length.
(c) Alleys shall be discouraged in residential district but should be included in commercial and industrial areas where needed for loading and unloading, or access purposes. Where alleys are platted they shall be 14 feet in width.
(3) All local and collector streets shall be properly related to special traffic generators such as industries, business districts, schools, churches, and shopping centers, to population densities, and to the pattern of existing and proposed land uses.
(4) Local streets shall be laid out to conform as much as possible to the topography, to discourage use by through traffic, to permit efficient drainage and utility systems, and to require the minimum number of streets necessary to provide convenient and safe access to the property.
(5) Rigid, rectangular "gridiron" street patterns are generally to be avoided, and the use of casually curvilinear streets, cul-de-sacs, or loop streets shall be encouraged where such use will result in a more desirable lay-out and relate better to the existing topography. On flat land, innovative, varying geometrical street patterns shall be encouraged where they are likely to enhance visual interest and a sense of order for those using them (e.g., non-grid rectilinear, trapezoidal, polygonal, or other geometric patterns).
(6) Proposed streets shall, where appropriate, be extended to the boundary lines of the tract to be subdivided unless this is prevented by topography or other physical conditions, or unless in the opinion of the Plan Commission such extension(s) is/are not necessary or desirable for the coordination of the layout of the subdivision under consideration with the existing street layout or for the most advantageous future development of adjacent tracts.
(7) In business and industrial developments, the streets and other access ways shall be planned in connection with the grouping of buildings, location of rail facilities, and the provision of alleys, truck loading and maneuvering areas, walkways, bikeways, and parking areas so as to minimize conflict of movement between the various types of vehicular and pedestrian traffic.
(D) Streets Design.
(1) Street (and alley when provided) shall be completed to grades shown on plans, profiles, and cross-sections, provided by the subdivider, and prepared by a registered professional engineer and approved by the Commission.
(2) The street shall be graded, surfaced and improved to the dimensions required by such plans, profiles and cross-sections and the work shall be performed in the manner prescribed in "Standard Specifications for Road and Bridge Construction and Maintenance" (current issue) of the Department of Transportation.
(3) The street pavement shall be of Portland cement concrete of a flexible pavement of a width as provided in this chapter and shall be constructed in accordance with design characteristics at least equal to those given below.
Design Characteristics of Street and Alley Pavement | ||||
Kind of Pavement and Thickness | Primary (in.) | Secondary (in.) | Local (in.) | Alley (in.) |
Design Characteristics of Street and Alley Pavement | ||||
Kind of Pavement and Thickness | Primary (in.) | Secondary (in.) | Local (in.) | Alley (in.) |
Portland Cement Concrete | 8 | 7 | 6 | 6 |
Flexible Surface - Asphaltic concrete, type "B" | 1½ | 1½ | 1½ | 1½ |
Binder - Asphaltic - concrete or bituminous coated blended aggregate | 5 | 3 | 3 | 3 |
Base - Compacted aggregate or water bound macadam | 8 | 8 | 6 | 4 |
Subbase - type II | 6 | 6 | 6 | 6 |
Total Thickness | 19½ | 17½ | 13 | 11 |
(4) Prior to placing the street and alley surfaces, adequate subsurface drainage for the street shall be provided by the subdivider. Subsurface drainage pipe, when required, shall be coated corrugated pipe or similar type not less than 12 inches in diameter approved by the Commission. Plans and profiles as built shall be filed with the Commission.
(5) Street Names. The sketch plan, as submitted, shall indicate names of proposed streets regarding the duplication of names and possible confusion. After reviewing them, the Administrator shall inform the subdivider of his recommendations for possible revision during the sketch plan review. Names shall be sufficiently different in sound and in spelling from other street names in the county or other nearby area so as to avoid confusion. A street, which is, or is planned as a continuation of an existing street, shall bear the same name.
(E) Access to Collector Streets. Where possible, lots in single family residential subdivisions fronting on collector streets shall be avoided and lots at the corners of intersections between local and collector streets shall front on the local street and have driveway access to it only and not to the collector street. In multiple family residential areas entrances to group parking lots shall have access only to collector streets (where possible) and such entrances shall be widely spaced.
(F) Access to Primary Arterials. Where a subdivision borders on or contains an existing or proposed primary arterial, the Commission may require that access to it be limited by one of the following means:
(1) The subdivision of the lots so as to back onto the primary arterial and front onto a parallel local street, no access shall be provided from the primary arterial and screening shall be provided within a strip of land along the rear property line of such lots;
(2) A series of cul-de-sacs, or loop streets entered from, and designed generally to be at right angles to an access street that is at some distance from and parallel to the arterial street, with the rear lines of their terminal lots backing onto the arterial.
(G) Street Regulatory Signs. The applicant shall provide and install a street sign at every street intersection within his subdivision as required by the Street Department. The city shall inspect and approve all street signs before issuance of certificates of occupancy for any residence on the approved streets.
(H) Street Lights. If installed will be in accordance with the specification set by the County Engineer.
(I) Reserve Strips. The creation of reserve strips shall not be permitted adjacent to a proposed street in such a manner as to deny access to it from adjacent property if such street is a local service street rather than a collector or arterial street. (See divisions (E) and (F) of this section.)
(J) Construction of Streets.
(1) Construction of Streets other than Cul-de-sacs. The arrangement of streets shall provide for the continuation of streets between adjacent subdivisions or other properties when such continuation is necessary for the convenient movement of traffic, for effective fire protection, for efficient provision of utilities, and where such continuation is in accordance with the Comprehensive Plan. If the adjacent property is undeveloped and the street must be a dead-end (stub) street temporarily, the right-of-way shall be provided for all such temporary dead-end streets, with the notation on the subdivision plat that land outside the normal street right-of-way shall revert to abuttors whenever the street is continued. Temporary turnarounds must be provided at the ends of such stub streets. The Commission may limit the length of temporary dead-end streets in accordance with the design standards in these regulations.
(2) Cul-de-sacs (Permanent Dead-end Streets). Where a street does not extend beyond the boundary of the subdivision and its continuation is not required by the Commission for access to adjoining property, its terminus shall normally not be nearer to such boundary than 50 feet. However, the Commission may require the reservation of an appropriate easement to accommodate drainage facilities, pedestrian traffic, or utilities. A cul-de-sac turnaround shall be provided at the end of a permanent dead-end street in accordance with county construction standards and specifications available from the County Engineer's office. For greater convenience to traffic and more effective police and fire protection, permanent dead-end streets shall be limited in length in accordance with the design standards in these regulations.
(K) Design Standards.
(1) General. In order to provide for streets of suitable location, width, and improvement to accommodate prospective traffic and afford satisfactory access for police, fire-fighting, snow removal, sanitation, and street maintenance equipment, and to coordinate street location in order to achieve a convenient system and avoid undue hardships to adjoining properties, the following design standards for streets are hereby required. (Street classifications may be indicated in the Comprehensive Plan, Thoroughfare Plan, or on the Official Map; otherwise, they shall be determined by the Commission.)
(2) Street Surfacing and Improvements. After the developer has installed sewer and water utilities, the applicant may be required to construct curbs and gutters and shall surface or cause the roadways to be surfaced to the widths prescribed in these regulations. Said surfacing shall be of such character as is suitable for the expected traffic and in harmony with similar improvements in the surrounding areas. Types of pavement shall be as determined by the County Engineer. Adequate provision shall be made for culverts, drains, and bridges. All street pavement, shoulders, drainage improvements and structures, curbs, turn-arounds, and sidewalks shall conform to all construction standards and specifications adopted by the Commission, City Engineer, or the county and shall be incorporated into the construction plans required to be submitted by the developer for plat approval.
(3) Excess Right-of-way. Right-of-way widths in excess of the standards designed in these regulations shall be required whenever, due to topography, additional width is necessary to provide for adequate and stable earth slopes. Such slopes shall not be in excess of three to one.
(4) Railroads and Limited Access Highways. Railroad rights-of-way and limited access highways where so located as to affect the subdivision of adjoining lands shall be treated as follows.
(a) In residential districts a buffer strip at least 25 feet in depth in addition to the normal depth of the lot required in the district shall be provided adjacent to the railroad right-of-way or limited access highway. This strip shall be part of the platted lots and shall be designated on the plat: "This strip is reserved for screening. The placement of structures hereon other than earth berms, walls, fences and other landscape screening devices approved by the Commission is prohibited."
(b) In districts zoned for business, commercial, or industrial uses, the nearest street extending parallel or approximately parallel to a railroad shall, wherever practical, be at a sufficient distance therefrom to ensure a suitable depth for commercial or industrial sites.
(c) Streets parallel to a railroad when intersecting a street, which crosses the railroad at grade shall, to the extent practicable, be at a distance of at least 150 feet from the railroad right-of-way. Such distance shall be determined with due consideration of the minimum distance required for future separation of grades by means of appropriate approach gradients.
(5) Intersections.
(a) Streets shall be laid out so as to intersect as nearly as possible at right angles. A proposed intersection of two new streets at an angle of less than 75 degrees shall not be acceptable. An oblique street should be approximately at right angles for at least 100 feet therefrom. Not more than two streets shall intersect at any one point unless specifically approved by the Commission.
(b) Proposed new intersections along one side of an existing street shall, wherever practicable, coincide with any existing intersection on the opposite side of such street. Street jogs with center-line offsets of less than 150 feet shall not be permitted except where the intersected street has separated, dual drives, without median breaks at either such intersection. Where local streets intersect with arterials, their alignment shall be continuous. Intersections of arterials shall be at least 800 feet apart.
(c) Minimum curb radius at the intersection of two local streets shall be at least 20 feet, and minimum curb radius at an intersection involving a collector street shall be at least 25 feet. Alley intersections and abrupt changes in alignment within a block shall have the corners cut off in accordance with standard engineering practice to permit safe vehicular movement.
(d) Intersections shall be designed with a flat grade wherever practical. In hilly or rolling areas, at the approach to an intersection a leveling area shall be provided having not greater than a 2% grade at a distance of 60 feet, measured from the nearest right-of-way line of the intersecting street.
(e) Where any street intersection will involve earth banks or existing vegetation inside any lot corner that would create a traffic hazard by limiting visibility, the developer shall cut such ground and/or vegetation (including trimming trees) in connection with the grading of the public right-of-way to the extent deemed necessary by the County Engineer to provide an adequate sight distance.
(f) The cross-slopes on all streets, including intersections, shall be 3% or less.
(6) Bridges of primary benefit to the applicant, as determined by the Commission, shall be constructed at the full expense of the applicant without reimbursement from the county. The sharing of expense for the construction of bridges not of primary benefit to the applicant as determined by the Commission, will be fixed by special agreement between the county and the applicant. Said cost shall be charged to the applicant pro-rata as the percentage of his land developed and so served.
(L) Street Dedications and Reservations.
(1) New Perimeter Streets. Street systems in new subdivisions shall be laid out so as to eliminate or avoid new perimeter half-streets. Where an existing half-street is adjacent to a new subdivision, the other half of the street shall be improved and dedicated by the subdivider. The Commission may authorize a new perimeter street where the subdivider improves and dedicates the entire required right-of-way width within his own subdivision's boundaries.
(2) Widening and Realignment of Existing Streets. Where a subdivision borders an existing narrow street or when the Comprehensive Plan, Official Map, Thoroughfare Plan, or zoning setback regulations indicate plans for realignment or widening of a street that would require use of some of the land in the subdivision, the applicant shall be required to improve and dedicate such streets at his own expense. Such frontage streets and other streets on which subdivision lots front shall be improved and dedicated by the applicant at his own expense to the full width required by these subdivision regulations. Land reserved for any street purposes may not be counted in satisfying the yard or area requirements of the Zoning Ordinance.
(Ord. 6-2002, passed 3-4-02) Penalty, see § 156.999