The arrangement, character, extent, width and locations of all streets within any subdivision shall be properly related to existing and planned streets as indicated in the county transportation plan; to reasonable circulation of traffic; to topographic conditions; to runoff of stormwater; to public convenience and safety; and to the proposed uses of the land to be served by the streets.
(A) Minimum specifications. The following minimum specifications apply specifically to residential subdivisions. At the recommendation of the County Engineer, higher standards comporting with accepted engineering practices may be imposed for streets in nonresidential subdivisions.
Type of Street | Minimum Right-of-Way Width (Feet) | Minimum Pavement Width1 (Feet) |
Type of Street | Minimum Right-of-Way Width (Feet) | Minimum Pavement Width1 (Feet) |
Alley | 20 | 182 |
Collector | 60 | 364 |
Land access | 50 | 324 |
Marginal access | 40 | 223 |
Private lane | 25 (access easement) | 20 |
1 As measured from back to back of curbs | ||
2 No curbs required | ||
3 Curb requirements may be waived by subdivision variance | ||
4 Reduced pavement widths may be allowed by a variance granted by the Land Use Committee or the County Board in accordance with § 92.077 if the subdivider agrees to provide excess off-street parking, or if the street is very short (less than 500 feet) and highly unlikely to be extended. | ||
(B) Topographical considerations. Grades of streets shall conform as closely as possible to the natural topography, but shall not exceed the maximum grade nor be less than the minimum grade indicated in division (A) above. All streets shall be arranged so that as many as possible of the potential building sites are at or above street grade.
(C) Through traffic discouraged. Marginal access and land access streets shall be laid out so as to discourage use through traffic. To effect a more desirable street layout, the use of curvilinear streets, cul-de-sacs or U-shaped streets is encouraged; the rigid rectangular gridiron street pattern should be avoided.
(D) Limited access to area service highways. Where a subdivision abuts or contains an existing or proposed area service highway, the subdivider may be required to limit access to the highway by one of the following means:
(1) The subdivision of lots so that they back onto the highway, and front onto a parallel marginal access or land access street (double frontage lots), coupled with the installation of screening along the rear lot lines of such lots;
(2) A series of cul-de-sacs, U-shaped streets or short loop streets entered from and generally at right angles to the highway, with the rear lot lines of the lots at the termini of the streets backing onto the highway; or
(3) A frontage road separated from the highway by a planting strip, but having access thereto at suitable points.
(E) Dead-end streets.
(1) Temporary stub streets. Streets shall be arranged to provide the continuation of collector streets between adjacent properties when such continuation comports with the county transportation plan, or is necessary for adequate traffic circulation, effective fire and police protection and efficient provision of utilities. If a street must dead-end temporarily because the adjacent property is undeveloped, the right-of-way shall be extended to the property line, and no strip that would prevent connections with future streets shall be reserved. A temporary turnabout shall be provided at the terminus of any temporary dead-end street.
(2) Permanent dead-end streets. The terminus of a permanent dead-end street shall not be closer than 50 feet to the boundary of an adjacent tract. A cul-de-sac turnaround, having a minimum right-of-way radius of 50 feet and a minimum pavement radius of 40 feet, shall be provided at the end of every permanent dead-end street.
(F) Alleys. Alleys may be built in single-family districts at the subdivider’s option. Alleys may be required in multiple-family districts and in commercial or industrial districts unless other adequate provisions for service access are made. Alleys should not intersect with one another nor change sharply in alignment. Adequate vehicular turnaround space shall be provided at the terminus of any dead-end alley.
(G) Intersections.
(1) Only two streets. Not more than two streets shall intersect at any one point.
(2) Right angles. Streets shall be laid out to intersect as nearly as possible at right angles. In no case shall two streets intersect at an angle less than 75 degrees. An oblique street shall be curved approaching an intersection, and shall be approximately at right angles with the intersection for at least 100 feet therefrom, unless the subdivider’s engineer recommends, and the County Engineer concurs, that a lesser distance would be in accordance with safe and accepted traffic engineering practices.
(3) Proper alignment. Proposed new intersections along one side of an existing street shall, wherever practicable, coincide with any existing intersection on the opposite side of the street. Street jogs with centerline offsets of less than 125 feet are prohibited, unless the intersected street has divided lanes without median breaks at either intersection.
(4) Rounded corners. Returns at intersections shall be made concentric, and shall be rounded by a radius of not less than 20 feet at the right-of-way line.
(5) Flat grade. An area having not greater than 3% slope for a distance of 100 feet from the nearest right-of-way line of the intersecting street shall be provided at the approach to any intersection.
(6) Maximum cross slope. The cross slope on all streets, including intersections, shall not exceed 3%.
(7) Adequate sight lines. Whenever any proposed intersection involves earth banks or existing vegetation on the triangular area shown in Figure 1, the ground or vegetation, including trees, shall be cut in connection with the grading of the public right-of-way to the extent necessary to provide an adequate sight distance.
(H) Horizontal curves. Where a street changes direction (for example, where a centerline deflection angle occurs), a circular curve having the minimum centerline radius indicated below shall be introduced. (See Figure 2.)
(1) Land access street: 75 feet.
(2) Collector street: 250 feet.
(I) Reverse curves. A tangent at least 100 feet long shall be introduced between reverse curves on land access and collector streets. (See Figure 3.)
(J) Dedication or reservation of right-of-way.
(1) When right-of-way must be dedicated. (This division (J)(1) does not apply to private streets.)
(a) The subdivider shall dedicate at least the minimum right-of-way indicated in division (A) above whenever he or she proposes to build any of the listed streets.
(b) Whenever the subdivider proposes to build any of the listed streets, he or she shall dedicate a right-of-way in excess of the stated minimum where, in the County Engineer’s professional opinion:
1. Due to topography, additional width is necessary to provide adequate sight lines; or
2. Due to the location of streams, railroad tracks and other topographic features, additional width is needed to construct bridges, underpasses or safe approaches thereto.
(2) When right-of-way must be reserved. The subdivider shall reserve a right-of-way in the instances stated below. If the governmental entity requiring the reservation has not purchased the right-of-way or acquired it through condemnation proceedings within one year from the date the final plat is recorded, the reservation shall cease to legally bind the subdivider.
(a) Whenever the state, the county or any township or municipality within the county has gone on record as desiring to relocate or construct any street or highway through or adjacent to any proposed subdivision, the subdivider shall reserve sufficient right-of-way in the locations prescribed by the governmental entity.
(b) Whenever a subdivision abuts an existing street that does not meet the standards set forth in division (A) above, the subdivider shall reserve sufficient right-of-way along the side of the street abutting the subdivision so that, when additional right-of-way is acquired on the other side, it will be possible to comply with the standards.
(3) Right-of-way not part of minimum setback. As noted in § 92.022, any land that is dedicated or reserved for public rights-of-way shall not be counted in determining compliance with the lot size and setback requirements set forth in the zoning code.
(K) Private lanes. In cases where lots do not directly abut or have direct access to a public street a private lane may be utilized provided the lane serves no more than four dwelling units but more than a single unit. If an additional lot is platted or desires to access the private lane, all properties must be resubdivided and meet all platting requirements herein, including, but not limited to, the minimum street specifications and improvement standards and drainage requirements.
(1) The private lane may be constructed in a manner consistent with typical driveway construction by using gravel or clean rock in lieu of concrete or asphalt provided the lane remains maintained and passable.
(2) A maintenance agreement shall be recorded establishing the arrangement for which the private lane will be maintained.
(3) The final plat shall include an access easement (as per § 92.030).
(4) The final plat shall show the location and the width of the private street.
(5) The final plat shall include a certificate stating essentially as follows:
“I, , owner of tract and the private road or street shown hereon, declare that the private road or street is not dedicated to the public, but shall remain private, to be maintained by and for the adjoining lot owners until such time that said street(s) is accepted by the appropriate township or Madison County, Illinois.”
(L) Private streets. A commercial or residential subdivision street may remain private without being dedicated to the public under the following circumstances:
(1) Minimum street specifications and improvements standards have been met;
(2) Adequate easement and maintenance agreements are in place;
(3) The final plat shall include a certificate stating essentially as follows:
“I, , owner of tract and the private road or street shown hereon, declare that the private road or street is not dedicated to the public, but shall remain private, to be maintained by and for the adjoining lot owners until such time that said street(s) is accepted by the appropriate township or Madison County, Illinois.”
(1993 Code, § 92.23) (Ord. passed 10-17-1956; Ord. passed 10-18-1978; Ord. 2012-05, passed 6-20-2012) Penalty, see § 92.999