(A) General:
1. The arrangement, character, extent, width, grade and location of all streets must be considered in their relation to existing and planned streets, 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. In the case of tentative plats for parts of tracts, where it appears necessary to the plan commission for the satisfactory overall development of an area, an owner may be required to prepare at least a street plan of his entire tract based upon proper topographic surveys before approval of any portion of such plan.
3. Whenever an area is subdivided into lots of forty thousand (40,000) square feet or more that may at a later date be resubdivided, consideration must be given to the street and lot arrangement of the original subdivision so that additional minor streets can be located to permit a logical arrangement of smaller lots.
4. In the layout of all subdivisions, due regard must be given to the preservation of historical sites and natural features such as large trees, watercourses and scenic views.
(B) Street Layout: The arrangement of streets in a subdivision must either:
1. Provide for the continuation or appropriate projection of existing principal streets in surrounding area; or
2. Meet a particular situation where topographical, drainage or other conditions make continuance or conformance to existing streets impracticable.
(C) Frontage Roads:
1. Where a subdivision abuts or contains an existing or proposed major highway or interstate highway, the plan commission may require:
(a) Frontage roads;
(b) Reverse frontage with screen planting contained in a nonaccess reservation along the rear property line;
(c) Deep lots with rear service alleys;
(d) Other treatments as necessary for protection of residential properties and to separate through and local traffic.
2. Where a subdivision borders on or contains a railroad right of way or limited access highway right of way, the plan 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, for park purposes in residential districts, or for commercial or industrial purposes in the appropriate districts. Such distances must be determined also with due regard for the requirements of approach grades and future grade separations.
(D) Half Streets Prohibited: No building permit will be issued for the construction of a building on a lot that abuts a public right of way dedicated to one-half (1/2) or less of its proposed width.
(E) Street Dimensions: All streets must conform to the following requirements:
Arterial Streets | Collector And Multi-Family Streets | Local Residential Streets | Frontage Roads | Business Parks | Industrial Parks |
Arterial Streets | Collector And Multi-Family Streets | Local Residential Streets | Frontage Roads | Business Parks | Industrial Parks | |
Right of way width | 80' - 100' | 70' | 66' (curb/ gutter); 66' (no curb/ gutter) | 50' | 80' - 100' | 80' - 100' |
Pavement width (back of curb to back of curb) | 48' - 72' | 36' | 33' (curb/ gutter); 24' (no curb/ gutter) | 28' | 48' | 40' |
Minimum radius of horizontal curves (road centerline dimension) | 600' | 400' | 100' | 200' | 500' | 400' |
Vertical curve sight distance (measured at 4.5' above the center of the roadway) | 400' | 300' | 200' | 200' | 400' | 400' |
Minimum tangents between reverse curves (road centerline dimension) | 200' | 200' | 100' | 100' | 200' | 200' |
Maximum gradient | 3% | 3% | 6% | 6% | 3% | 3% |
Minimum gradient | 0.4% | 0.4% | 0.4% | 0.4% | 0.4% | 0.4% |
Minimum curb tangents at street intersections | 30' | 25' | 25' | 25' | 30' | 30' |
(F) Intersections:
1. Streets must intersect as nearly to right angles as possible, with no intersection less than sixty degrees (60°).
2. Street jogs with centerline offsets of less than one hundred twenty five feet (125') are prohibited.
(G) Cul-De-Sac Streets:
1. Permanent dead end streets may not be longer than eight hundred feet (800') and must be provided with a cul-de-sac turnaround with a pavement radius of at least forty five feet (45') and a right of way radius of at least sixty five feet (65'). Other types of turnarounds are prohibited.
2. Where a cul-de-sac island is provided, the island must be landscaped and the pavement width must be twenty seven feet (27'). Landscape islands within cul-de-sac islands must be maintained by the adjoining property owners or established homeowners' association.
(H) Stub Streets:
1. Where an existing street terminates at the boundary line of a proposed subdivision, the street must be continued in the proposed subdivision unless natural conditions on the adjacent property preclude continuation of the street.
2. When a proposed street terminates at the subdivision boundary, right of way lines and pavement must extend to the subdivision boundary if the adjacent property is undeveloped. The following notation must be placed on the final plat: "Future access connection for adjacent development".
(I) Alleys:
1. Alleys are prohibited in residential areas except where approved by the plan commission.
2. Alleys may be required in commercial and industrial districts. The plan commission must refer any variations to the city council for waiving this requirement if provisions are made for service access such as off street loading, unloading and parking, consistent with and adequate for the uses proposed.
3. Where provided, alleys must have a minimum right of way width of twenty feet (20').
4. Alley intersections and sharp changes in alignment must be avoided where possible, but where necessary, corners must be cut off sufficiently to permit safe vehicular movement.
5. Dead end alleys must be avoided where possible, but if unavoidable, must be provided with adequate turnaround facilities at the dead end, as determined by the plan commission.
(J) Surfacing: The following types of street surfacing are minimum requirements:
1. Local Residential Streets:
(a) Three inch (3") bituminous surface on an eight inch (8") compacted aggregate base; or
(b) Six inch (6") concrete surface on a four inch (4") compacted aggregate base.
2. Arterial And Collector Streets: Four inch (4") thick bituminous surface on a twelve inch (12") compacted aggregate base.
(K) Curbs And Gutters:
1. Concrete curbs (type B-6.12 as specified in the most recent edition of the highway standards of the Illinois department of transportation) must be installed on all new streets, except in detached single-family subdivisions where a mountable curb of similar dimensions may be approved by the city engineer, the planning commission, and the city council.
2. Where curb and gutter are not required, streets must be constructed with:
(a) Three inch (3") thick bituminous surface on eight inch (8") compacted aggregate base for street construction;
(b) Shoulders consisting of the same material as the required aggregate base course, extending two feet (2') beyond each edge of the bituminous surface;
(c) Ditches a minimum of two feet (2') deep with slopes no steeper than four to one (4:1); and
(d) Minimum twelve inch (12") diameter pipe culverts for driveways and minimum fifteen inch (15") diameter pipe culverts for crossroad culverts.
(L) Street Names: Street names may not be similar to or duplicate the names of existing streets. New streets that are extensions of existing streets must bear the name of the existing street. All street names are subject to the approval of the plan commission.
(M) Street Signs And Markers: The subdivider must purchase and install street name signs that conform to the standards of the city at one corner of each street intersection.
(N) Streetlights: Streetlights must be installed at all intersections and at the end of all cul-de-sac and stub streets. Installation of lighting must meet all current city specifications. Payment must be made by the developer to the city for the installation of lighting standards, poles, brackets, luminaries, lamps and wiring meeting all current city specifications. (Ord. 1379, 6-9-2008)