The design of a subdivision shall conform to the following design standards:
(A) Conformity to the major street plan. The width and locations of all streets in a proposed subdivision will conform to the Major Street Plan.
(B) Relation to topography. Streets shall be designed with respect to topography to produce the most usable and properly situated lots, provide proper drainage for storm water, and produce proper grades.
(C) Street extensions.
(1) Extension of present streets. The street layout of the proposed subdivision shall provide for the continuation or extension of streets already existing in areas adjacent to the area being subdivided unless the Planning Commission deems such continuation or extension undesirable for specific reasons of topography or design.
(2) Extension of proposed streets. Where, in the opinion of the Planning Commission, it is desirable to provide street access to adjoining properties, proposed streets shall be extended by dedication to the boundaries of such properties. Where the Planning Commission deems it necessary, such dead-end streets shall be provided with a temporary turn-around having a radius of at least 40 feet.
(3) Required width. The street system for the proposed subdivision shall provide for extending existing streets at the same or greater width, but in no case shall a street extension be of less width than the minimum width required in these regulations for a street in its category.
(D) Dedication of right-of-way.
(1) New streets. The dedication of rights-of-way for new streets measured from the lot line to the lot line shall be as shown on the General Plan, or if not shown thereon, shall meet the following standards.
Street Type Right-of-Way (Feet)
Arterial streets 80
Collector streets 60
Minor streets - through streets 50
Minor streets - local streets
(cul-de-sacs less than 400
feet with only single dwell-
ing units and loop streets
"off collectors less than
2,000 feet around" with only
single family dwelling units) 50
(2) Maximum dedication. The Major Street Plan may indicate greater right-of-way widths for certain arterial streets, but in no case shall the subdivider be required to dedicate a right-of-way width of more than 80 feet for any one street.
(3) Arterial streets with controlled access. All streets classified as arterial streets by the General Plan may be considered as limited access in accordance with KRS 177.220 through 177.310, defined herein as controlled access. All points of access shall be as approved by the Planning Commission.
(4) Marginal access streets. Where the proposed subdivision abuts upon or contains an existing or proposed arterial street or highway on which traffic volumes and vehicular speeds warrant special safety considerations, the Planning Commission may require that marginal access streets be provided in order that no lots will front on such existing or proposed arterial street or highway.
(5) Dead-end streets (cul-de-sacs). Minor terminal or dead-end streets or courts which are designed so as to have one end permanently closed shall not be longer than 500 feet and shall be provided at the closed end with a turn-around having a radius at the outside of the right-of-way of at least 50 feet.
(6) Alleys. Alleys shall be provided to give access to the rear of all lots used for business and industrial purposes. Alleys shall not be provided in residential blocks except in cases where the subdivider produces evidence of the need for alleys which is satisfactory to the Planning Commission.
(7) Existing streets.
(a) Subdivision on both sides of street. Where the subdivision is on both sides of an existing street, sufficient right-of-way shall be dedicated to give the street the required right-of-way.
(b) Subdivision on one side of street. Where the subdivision is to take place on only one side of a street, one-half of the right-of-way needed to give the street the required right-of-way shall be dedicated.
(8) Increased right-of-way necessary. If the Planning Commission deems it necessary, street rights-of-way through commercial zones or present on proposed business areas shall be increased ten feet on each side for needed parking.
(9) Extraordinary physical conditions. If the Planning Commission deems it necessary where extraordinary physical conditions exist, the Planning Commission may alter the right-of-way requirements.
(10) Streets along property lines. Where a proposed street runs along a property line of the proposed subdivision, the street right-of-way, pavement, and other requirements must be met in full.
(11) Conflicting traffic or land use. When a proposed subdivision contains or is adjacent to existing or proposed railroad rights-of-way, arterial street right-of-way, other significant rights-of-way, or conflicting and detrimental land uses; the Planning Commission may require marginal access streets, reverse frontage lots, lots with rear service alleys, lots with additional depth, or other measures which may be necessary for protection of abutting properties and the maintenance or function of major traffic arteries.
(E) Private streets and reserve strips.
(1) There shall be no private streets platted within a subdivision.
(2) There shall be no reserve strips in a subdivision except where their control is definitely vested in the city or county under conditions approved by the Planning Commission as authorized in these regulations.
(F) Street intersections.
(1) Number of approaches. Intersections involving more than four basic street approaches shall be prohibited. Merging lanes and deceleration lanes are considered as parts of one street approach.
(2) Angle at intersection. For a tangent distance of at least 100 feet, measured from the intersection of right-of-way lines, all streets should intersect at an angle of 90 degrees. In no case shall the angle of intersection be less than 75 degrees.
(3) Radii at intersection. Street curb and edge intersections shall be rounded by radii of at least 20 feet.
(4) Street jogs. Street jogs with center line offsets of less than 150 feet shall not be made.
(G) Horizontal curves.
(1) Reverse curves. A tangent at least 100 feet long shall be introduced between reverse curves on arterial and collector streets.
(2) Curve radius. Where there is a deflection angle of more than ten degrees in the alignment of a street, a curve with a radius adequate to insure safe sight distance shall be made. The minimum radii of curves shall be:
Street Type | Minimum Curve Radius (Feet) |
Arterial | 300 |
Collector | 300 |
Minor | 100 |
(H) Vertical curves.
(1) All changes in grade for streets shall be connected by a vertical curve of a minimum length necessary to provide adequate sight distance and other safety factors.
(2) To calculate the minimum length for the curve connecting changes in grade:
(a) Calculate the algebraic difference in grades.
(b) Multiply by the appropriate value.
Values for Arterial and collector 50
crest curve streets
Minor streets 28
Values for Arterial and collector 50
sag curve streets
Minor streets 35
(I) Street grades.
(1) Maximum grades. Street grades shall conform to the following:
Percent Grade
Allowable Desirable
Street Type Maximum Maximum
Allowable Desirable
Street Type Maximum Maximum
Arterial 5 4
Collector 7 5
Minor 12 8
(2) Grades for drainage. All streets shall be designed so as to provide for the discharge of surface water from the pavement and from the right-of-way by grading and drainage. For adequate drainage, the minimum street grade shall not be less than one-half of one percent.
(3) Excessive grades at intersections. When a street grade at the approach to an intersection exceeds three percent, a leveling area shall be provided with grades of not greater than three percent for a distance of 50 feet from the intersection of street center- lines. Vertical curves shall then be used to connect the intersecting grades.
(J) Street elevations.
(1) Streets shall be flood free. The Planning Commission shall not approve streets which will be subject to inundation or flooding. All streets must be located at elevations which will make them flood free in order that portions of the subdivision will not be isolated by floods. Where flood conditions exist, the Planning Commission shall require profiles and elevations of streets in order to determine the advisability of permitting the proposed subdivision activity.
(2) Fills. Fill may be used in areas subject to flooding in order to provide flood-free streets if such fill does not unduly increase flood heights. Drainage openings shall be designed as not to restrict the flow of water and thereby unduly increase flood heights. Such fills and openings shall be approved by the City Engineer.
(K) Access to lots.
(1) Lots on or near arterial streets. Access to lots abutting only on arterial rights-of-way shall conform to § 155.10 (D) (3) but in no case shall the access be closer than 125 feet from an intersection. A lot which abuts a street which intersects an arterial shall have access only to the nonarterial street at a distance of not less than 75 feet from the intersection.
(2) Lot on or near collector streets. A lot which abuts only on a collector shall have access to the lot at a distance not less than 75 feet from an intersection. A lot which abuts a minor street which connects with a collector shall have access to only the minor street at a distance not greater than 50 feet from the collector.
(3) Minor streets. Lots which abut only on minor streets shall have access at a distance not greater than 50 feet from an intersection. Lots that abut on a cul-de-sac shall have access only to a cul-de-sac.
(4) Marginal access streets. Lots abutting on marginal access streets shall have access at a distance no greater than 75 feet from an intersection. If a lot abuts both an arterial street or collector and a marginal access street, access shall be given only along the marginal access street.
(5) Alleys. All nonresidential lots may have access to an alley, except that an alley cannot be used as the primary access point to a commercial or industrial use or other uses which generate a large volume of traffic.
(1) Street names.
(1) Proposed streets which are obviously in alignment with other already existing and named streets shall bear the names of such existing streets.
(2) The name of a proposed street which is not in alignment with an existing street shall not duplicate the name of any existing street, irrespective of the use of the suffix street, avenue, boulevard, drive, place, court, lane, road, pike, highway, parkway, or similar suffix.
(Ord. 682, passed 2-22-79) Penalty, see § 155.99