§ 157.50 SPECIFICATIONS.
   (A)   The thoroughfare and street layout, and alley layout where permitted, shall provide access to all lots and parcels of land within the subdivision. When two roads or streets intersect the same street (T-intersection), offsets less than 125 feet shall not be permitted.
   (B)   Alleys shall not be permitted in those parts of the plat proposed for single-family and two-family residential use. Service roadways may be required in commercial and industrial developments, except where other provisions for suitable access and off-street loading and unloading is assured. No dead-end alleys shall be permitted.
   (C)   Pavement construction standards for service roadways and alleys where permitted, shall conform to the “Standard Specifications for Road and Bridge Construction,” latest amended edition, adopted by the Illinois Department of Transportation.
   (D)   Half-streets are prohibited except when a half-street has been previously platted abutting the tract boundary line, the remaining half-street shall be platted and improved within the tract. In cases where the platting of a half-street is approved, it shall not be constructed or used for access to any lot until such time as the adjoining half-street is platted, approved, and the entire street is constructed.
   (E)   Rights-of-way widths: see Appendix A, Table 1.
   (F)   Partial rights-of-way widths: in those instances in which the owner or owners of a new subdivision own land on only one side of an existing road or street and the rights-of-way is narrower than that required by these regulations, the owner shall dedicate additional rights-of-way lying between the center line of the existing rights-of-way and the outside edge of the additional rights-of-way at least equal to one-half of the required rights-of-way width.
   (G)   The angle of intersection between local roads and streets and collector and arterial roads shall not vary by more than ten degrees from the right angle. All other local roads and streets shall intersect each other as near to a right angle as possible and in no case shall an angle of less than 70 degrees be permitted.
   (H)   Intersections of three or more roads or streets at any one point shall be prohibited.
   (I)   Where parkways or special types of roads or streets are involved, the reviewing authorities may apply special standards to be followed in their design.
   (J)   Horizontal visibility on curved streets and vertical visibility on all roads and streets shall be maintained along the centerline. See Appendix A, Table 1.
   (K)   Curvature measured along the centerline shall have a minimum radius. See Appendix A, Table 1.
   (L)   Maximum grades for roads, streets, and thoroughfares are herein established. See Appendix A, Table 1.
   (M)   Whenever the proposed subdivision contains or is adjacent to a railroad rights-of-way or a highway designated as a limited access highway by the appropriate highway authorities, provisions shall be made for a parallel thoroughfare.
   (N)   Roads, streets, alleys where permitted, and other thoroughfares shall be designed in consideration to their relation to existing and planned roads, streets, thoroughfares; to reasonable circulation of traffic; to topographical conditions; to runoff conditions; to extraordinary future public maintenance and replacement costs; and, in their appropriate relation to the proposed uses of the land to be served by such roads, streets, and thoroughfares.
   (O)   Stormwater systems, roads, streets, alleys where permitted, and other thoroughfares shall have complete plans, profiles, and cross sections, provided by the subdivider and prepared by an Illinois Registered Professional Engineer.
   (P)   Roads, streets, alleys where permitted, and other thoroughfares shall be graded, surfaced, and improved to the dimensions as approved and work shall be performed in the manner prescribed in “Standard Specifications for Road and Bridge Construction,” latest amended edition, adopted by the Department of Transportation of the State of Illinois.
   (Q)   Minimum road surface widths are hereby established by these regulations. See Appendix A, Table 1. Where a subdivision is being platted upon an existing road, such road must be improved by the developer to meet the minimum standards established for the classification of that road and herein contained. Where use of an existing road or thoroughfare is to be shared between subdivision use and any general public use, required improvements above the minimum standards will be considered on a cost-sharing basis between the developer and the road or thoroughfare authority.
   (R)   All roads, streets, alleys where permitted, and other thoroughfares in any subdivision shall have a drainage plan conforming to all state, county, local, and federal laws and regulations applicable and shall represent best modern engineering practices.
   (S)   The diameter of the paved surface of a permanent turnaround shall not be less than 120 feet.
   (T)   Spite or reserve strips controlling access to public roads, streets, rights-of-way, actual or proposed, shall be prohibited.
   (U)   Dead-end or stub-end streets are prohibited. A road or street permanently ending in a cul-de-sac shall not be considered “dead-end” for purposes of these regulations.
   (V)   All streets, roads, and other thoroughfares providing primary means of access to property shall be named. Names of streets, roads, and thoroughfares in a proposed plat shall be chosen to avoid confusion and duplication with existing names, especially with such names located within the jurisdiction supplying fire protection to the site. The developer shall be responsible for the purchase and erection of road and street name signs resulting from the development and shall construct and locate such signs according to the direction of the applicable City or Township Road Commissioner.
   (W)   Traffic control and warning devices whose need is created by the subdivision shall be purchased and erected by the developer.
   (X)   Maximum length of permanent cul-de-sac streets shall be 600 feet measured from the centerline of the intersection of the street to the center of the turning circle. Each cul-de-sac shall be provided at the closed end with a turn around having a minimum diameter of 120 feet, and a minimum street rights-of-way line diameter of 120 feet. No cul-de-sac may intersect with another cul-de-sac.
(Ord. 88-4582, passed 10-18-1988)