(a) Generally. The standards set forth in this section are the minimum standards for streets, roads and intersections. The arrangements, character, extent, width, grade and location of all streets shall conform to the Master Plan as adopted by the Planning Commission and to the standards of the Southeast Michigan Inter-County Highway Commission, and shall be considered in their relation to existing and planned streets, topographic conditions and public convenience and safety and in their appropriate relation to proposed uses of the land to be served. All streets shall be dedicated to public use.
(b) Rights of Way.
(1) Width. Public rights of way shall not be less than set forth in the following table:
Type of Right of Way Width (ft.)
Parkway or boulevard 120
Arterial street 120
Collector street 90
Minor street, including a cul-de-sac 66
(2) Inadequate rights of way. Where a subdivision abuts or contains an existing street of inadequate right-of-way width, additional width for the existing street may be required to achieve conformity with the minimum standards.
(3) Additional right-of-way width in dense areas. Additional right-of-way width may be required to ensure adequate access, circulation and parking in high density residential, commercial or industrial areas of subdivisions.
(c) Location and Arrangement.
(1) Local or minor streets. Local or minor streets shall be so arranged as to discourage their use by through traffic.
(2) Street continuation and extension. The arrangement of streets shall provide for the continuation of existing streets from adjoining areas into new subdivisions, unless otherwise approved by the Planning Commission.
(3) Stub streets. Where adjoining areas are not subdivided, the arrangement of streets in new subdivisions shall be extended to the boundary line of the tract to make provision for the future projection of streets into adjacent areas.
(4) Relation to topography. Streets shall be arranged in proper relation to topography so as to result in usable lots, safe streets and reasonable gradients.
(5) Alleys. Alleys are not permitted.
(6) Marginal access streets. Where a subdivision abuts or contains an arterial street, the City may require:
A. Marginal access streets approximately parallel to and on each side of the right of way; and
B. Such other treatment as it deems necessary for the adequate protection of residential properties and to afford separation of through and local traffic.
(7) Cul-de-sacs. A cul-de-sac shall be not more than 500 feet in length. Special consideration shall be given to a longer cul-de-sac under certain topographic conditions or other unusual situations. A cul-de-sac shall terminate with an adequate turn-around with a minimum external diameter of 150 feet.
(8) Half streets. Half streets are prohibited, except where unusual circumstances make it essential to the reasonable development of the tract in conformity with these Subdivision Regulations and where satisfactory assurance for dedication of the remaining part of the street is provided. Whenever a tract to be subdivided borders on an existing half or partial street, the other part of the street shall be dedicated within such tract.
(9) Private streets. Private streets and roads are prohibited.
(d) Gradients and Alignment.
(1) Gradients. Street grades shall not exceed five percent on either local streets or collector streets, except under unusual topographical conditions.
(2) Alignment.
A. Horizontal alignment. When street lines deflect from each other by more than ten degrees in alignment, the centerlines shall be connected by a curve with a minimum radius of 500 feet for arterial streets, 300 feet for collector streets and 150 feet for local or minor streets. Between reverse curves, on minor streets, there shall be a minimum tangent distance of 100 feet, and on collector and arterial streets, 200 feet. This requirement may be less under unusual topographical conditions.
B. Sight distance. Minimum centerline sight distance shall be 200 feet for minor streets and 300 feet for collector streets, unless unusual topographical conditions dictate otherwise. Sight distance shall be measured at the eye height of three and three-fourths feet to an object height of six inches.
(e) Street Names. A street name may not duplicate that of an existing street in the County except where a new street is a continuation of an existing street. Street names that may be spelled differently but sound the same shall also be avoided. Street names may be rejected by either the County Road Commission or the City.
(f
(f) Intersections.
(f) Intersections.
(1) Angle. 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 seventy-five degrees is not acceptable. An oblique street shall be curved approaching an intersection and shall be approximately at right angles for at least fifty feet therefrom.
(2) Sight Triangles. Minimum clear sight distance at a minor street intersection shall permit vehicles to be visible to the driver of another vehicle when each is 125 feet from the center of the intersection. This requirement is increased to 180 feet for collector streets and 260 feet for arterial streets.
(3) Number of streets. Not more than two streets shall cross at any one intersection.
(4) "T" intersections. Except on arterial streets and certain collector streets, "T" intersections shall be used where practical.
(5) Centerline offsets. Slight jogs at intersections shall be avoided. Where such jogs are unavoidable, parallel street centerlines shall be offset by a distance of 150 feet or more.
(6) Vertical alignment. A nearly flat grade is desirable within intersections. The flat section shall be carried back sixty feet each way from the intersection measured from the nearest right-of-way line of the intersecting street.
(Ord. 421. Passed 6-1-82.)