(A) The arrangement of highways shall conform as nearly as possible to the County Comprehensive Plan. Except for cul-de-sacs, roads and streets normally shall connect with roads and streets already dedicated in adjoining or adjacent subdivisions, or provide for future connections to adjoining unsubdivided tracts, or shall be a reasonable projection of roads in the nearest subdivided tracts. The arrangement of highways shall be considered in their relation to the reasonable circulation of traffic, to topographic conditions, to runoff storm water, to public convenience and safety and in their appropriate relation in the proposed uses of the area to be served.
(B) Local roads and streets should be so planned as to discourage their use by non-local traffic. Dead-end streets and roads shall be prohibited, but cul-de-sacs or approved “Tee” will be permitted where topography or other conditions justify their use. Cul-de-sacs shall not be longer than 500 feet, including a terminal turn-around which shall be provided at the closed end, with an outside curb radius of at least 60 feet and a right-of-way radius of not less than 66 feet or an approved “Tee”.
(C) Where the plat to be submitted includes only part of the tract owned or intended for development by the subdivider, a tentative plan of a proposed future street and road system for the unsubdivided portion shall be prepared and submitted by the subdivider.
(D) When a tract is subdivided into larger than normal building lots or parcels, such lots or parcels shall be so arranged as to permit the logical openings of future roads and appropriate resubdivision, with provision for adequate utility connections for such resubdivision.
(E) Under normal conditions, roads shall be designed so as to intersect as nearly as possible at right angles, except where topography or other conditions justify variations. Under normal conditions, the minimum angle of intersection of roads shall be 80 degrees. Road intersection jogs with an offset of less than 200 feet shall be avoided.
(F) Wherever the proposed subdivision contains or is adjacent to the right-of-way of a county, state or federal highway, provision shall be made for a marginal access street or road approximately parallel and adjacent to the boundary of such right-of-way, or for a road at a distance suitable for the appropriate use of land between such road and right-of-way. Such distance shall be determined with due consideration for the minimum distance required for approach connections to future grade separations, or for lot depths. In platted subdivisions, individual lots will have no direct access to any county, state or federal highway.
(G) Alleys shall be provided in commercial and industrial districts; except that, this requirement may be waived where other definite and assured provisions are made for service access, such as on-site loading, unloading and parking consistent with and adequate for the uses proposed. Except where justified by special conditions, such as the continuation of an existing alley in the same block, alleys will not be approved in residential districts. Alleys, where provided, shall not be less than 20 feet wide. Dead-end alleys shall be avoided wherever possible, but, if unavoidable, such dead-end alleys may be approved if adequate turn-around facilities are provided at the closed end.
(H) Dedication of half streets or roads will not be approved, except where it is essential to the reasonable development of the subdivision and in conformity with the other requirements of these regulations, where it is found that it will be practical to require the dedication of the other half when the adjoining property is subdivided, or where it becomes necessary to acquire the remaining half by condemnation so that it may be improved in the public interest.
(I) (1) For all public ways hereafter dedicated and accepted, the minimum right-of-way widths for streets, roads and highways shall be as shown in the County Comprehensive Plan, and where not shown therein, the minimum right-of-way width for streets, roads, highways, alleys or pedestrian ways included in any subdivision shall not be less than the minimum dimensions for each classification as follows:
Arterial highways | |
Alley | 20 feet |
Local streets and roads | 66 feet |
Marginal service access roads | 50 feet |
Minor arterial highway | 100 feet |
Pedestrian way | 10 feet |
Principal arterial highway | 130 feet |
Major intercity and regional highways | |
Major intercity highway | 150 feet |
(2) Where the existing or anticipated traffic on major and minor arterial highways warrants greater widths of right-of-way, these shall be required. Right-of-way widths for major intercity highways shall also meet standards established by the state’s Highway Department. Where any platted subdivision abuts a public road including a township road, right-of-way dedication from centerline of public road shall be provided in compliance with above schedule but in no case shall said dedication be less than 50 feet.
(3) No exclusion of roads wholly within subdivision.
(J) Minor street access to existing highways shall not be permitted at intervals of less than 600 feet.
(K) (1) The grades in all streets, roads, highways and alleys in any subdivision shall not be greater than the maximum grades for each classification as follows:
Arterial highways | |
Alley | 8% |
Local streets and roads | 8% |
(2) In addition, there shall be a minimum grade on all roads and highways of not less than 0.5%.
(L) The horizontal and vertical alignment standards on all roads, highways and streets shall be as follows.
(1) Horizontal, radii of centerline.
Arterial highways | |
Local streets and roads | 100 feet |
Minor arterial highways | As required by the state’s Transportation Department |
Principal arterial highways | As required by the state’s Transportation Department |
Major intercity highways | |
Major intercity expressway | As required by the state’s Transportation Department |
Major intercity highways | As required by the state’s Transportation Department |
NOTES TO TABLE: There shall be a tangent between all reversed curves of a length in relation to the radii of the curves so as to provide for a smooth flow of traffic. | |
(2) Vertical, all changes in street grades shall be connected by vertical parabolic curves of such length as follows.
Arterial highways | 30 times the algebraic difference in the percent of grade of the 2 adjacent slopes |
Local streets and roads | 20 times the algebraic difference in the percent of grade of the 2 adjacent slopes |
Major intercity highways | As required by the state’s Transportation Department |
(M) Subdivision road cross-section requirements.
(1) Width.
(a) All roads shall be subgraded to 32 feet minimum.
(b) Five ton aggregate base shall be consist of either:
1. Four inches of Class 5 on top of four inches of Class 3 or 4; or
2. Seven inches of Class 5.
(c) Bituminous surface two inches thick and 22 feet wide shall be completed at such time as 65% of the individual lots in the subdivision are sold.
(d) Road base shall be at standard immediately before blacktopping and approved by the County Engineer.
(2) Structure of roads.
(a) Five-ton aggregate base shall be applied first.
(b) A seven-ton roadway shall have a minimum two inches of bituminous.
(3) Ditches.
(a) Side slope shall be a minimum three to one.
(b) Ditch bottom shall have a width minimum of four feet.
(c) Ditch depth shall be two feet from shoulder at minimum.
(N) All proposed public streets or roads shall be offered for dedication as public right-of-way. Private street or roads shall not be permitted, except upon approval as part of a planned unit development or in other instances when specifically recommended by the County Planning Commission.
(Ord. passed 12-11-1979)