[Amended 6-20-2023 by Ord. No. 1996]
The arrangement, character, extent, width, grade, and location of all streets shall conform as near as possible to the Comprehensive Plan and shall be considered in their relation to existing and planned streets, to 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.
A. Overall roadway system design.
(1) The roadway system shall be designed to permit safe and orderly movement of vehicular and pedestrian traffic to meet, but not exceed, the needs of the present and future served population; to be simple and logical; to respect natural features, topography, and landscape; and to present an attractive streetscape.
(2) The roadway system shall conform to the City's Comprehensive Plan. For streets not shown on the Comprehensive Plan, the arrangement of such streets shall provide for the logical extension of existing streets and streets shown on the Comprehensive Plan.
(3) The internal street network of a subdivision should provide for logical, continuous extensions of streets to and from adjacent subdivisions, both existing and those yet to be platted.
(4) The roadway system shall provide adequate traffic flow through a subdivision and provide at least two (2) routes from each lot within the subdivision to the rest of the City, except as explicitly permitted by the City Council and any governmental agency with jurisdiction over the applicable roadway system. Additionally, the roadway system should be designed to discourage through traffic from using local streets and local traffic from using arterials.
(5) The roadway system shall provide an internal street network that creates a high level of connectivity as defined in the Comprehensive Plan.
(6) The roadway system shall provide through routes within subdivisions that allow direct and continuous access to the adjacent arterial and collector street network. Such through routes shall be direct in nature with continuous access that allows easy navigation between the arterial and collector street network. At least three north-south and three east-west through routes shall be provided per mile unless the City Engineer and Planning Director determine that through routes are not feasible due to topography, environmental sensitivity, or other condition as deemed appropriate by the City Engineer and Planning Director. Such through routes shall be generally located at the quarter (1/4) and half (1/2) mile intersections with the adjacent streets as depicted on Figure 170-16(A)(6). The half (1/2) mile routes shall provide the most direct routes between the adjoining arterial and collector streets. Alternate routes that provide through routes at locations other than the quarter (1/4) or half (1/2) mile; provided that the City Engineer and Planning Director determine that such alternate route is required due to topography, environmental sensitivity, human conflicts, or other condition as deemed appropriate by the City Engineer and Planning Director.
Figure 170-16(A)(6): Subdivision Through Routes |
B. Street extensions. The roadway system, including the internal street network, of the proposed subdivision shall provide for the continuation or appropriate projection of streets and alleys already existing in areas being subdivided. Where, at the determination of the City Council, 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 City Council deems it necessary, such dead-end streets shall be provided with a temporary turnaround having a radius of at least 50 feet or an equivalent means as authorized by the City Engineer. The roadway system, including the internal road network, of the proposed subdivision shall provide for extending existing roads, but in no case shall a road extension be of less width than the minimum width required in these regulations based on the road classification.
C. Dedication of right-of-way for new streets. The dedication of right-of-way for new streets measured from lot line to lot line shall meet the right-of-way requirements as provided in Table II of these regulations. All points of access to all streets classified as arterial or collector streets shall be subject to the approval of the City Council. Marginal access streets may be required by the City Council for subdivisions fronting on arterial streets.
D. Dedication of right-of-way for existing streets. Subdivisions platted along existing streets shall dedicate additional right-of-way, if necessary, to meet the minimum street width requirements set forth in these regulations. The entire minimum right-of-way width shall be dedicated where the subdivision is on both sides of an existing street. When the subdivision is located on only one side of an existing street, 1/2 of the required right-of-way width, measured from the center line of the existing roadway, shall be dedicated.
E. Intersections.
(1) Intersection design.
(a) Conflicts at intersections shall be minimized.
(b) Adequate stopping sight distances shall be provided, as deemed necessary by the City Engineer, to allow drivers to react to potential conflicts and stop.
(c) Adequate intersection sight distances shall be maintained to provide opportunity for a driver who is waiting at an access point to enter or cross the street.
(d) An area upstream and downstream shall be provided from any access point where drivers will need to change speed, brake, or maneuver should a vehicle turn onto the street.
(e) Appropriate spacing shall be provided to eliminate interference between two or more vehicles attempting to enter the street at the same time.
(f) The function area necessary to minimize congestion shall be provided in the area extending upstream and downstream of the physical intersection (including the longitudinal limits of the auxiliary lanes).
(2) Street intersections. Streets shall intersect as nearly as possible at an angle of 90°, and no intersection shall be at an angle of less than 75° unless specifically approved by City Council. Street curb intersections shall be rounded by a radius of at least 25 feet for residentially zoned lots and 35 feet for all other zoning districts. When the smallest angle of street intersection is less than 75°, the City Engineer may require curb radii of greater length. In all cases, the intersection radii shall not reduce the sidewalk width to less than five feet and shall allow for PROWAG compliant ramps which adhere to the standard City curb ramp details. As necessary, property lines at such street corner shall be chamfered or otherwise set back sufficiently to permit such curb, sidewalk, and curb ramp construction. No lot or other parcel of land which abuts on and has access to either a collector or a minor street shall have a service drive, curb cut, or other means of access within 75 feet of the right-of-way of such arterial street.
(3) Driveway intersections. Driveways shall align with adjacent driveways or streets to the maximum extent possible in order to prevent offset intersections. For nonresidential use type classifications, a minimum of 150 feet between driveways shall be required. When a driveway is located across from and between two other driveways that are on the opposite side of the street and unable to align, such driveway should be equally spaced between the opposing driveways.
(4) Traffic signal placing. Traffic signal placing shall be permitted at no closer than 1,320 feet to maximize signal progression, capacity, and speed.
(5) Access spacing requirements.
(a) Spacing required. Full access to minor and major arterial may be permitted at quarter (1/4) mile, half (1/2) mile, and one mile intervals. The preferred spacing for between two full access intersections is 1,320 feet; however, a minimum spacing of 1,200 feet is required. Right-in, right-out access may be permitted at the eighth (1/8) mile interval. The preferred spacing between a full access intersection and a right-in, right-out intersection is 660 feet; however, a minimum spacing of 500 feet is required. Such spacing requirements are depicted on Figure 170-16(E)(5).
Figure 170-16(E)(5): Access Spacing |
(b) Interim measures permitted. Interim access control measures may be permitted until the City Engineer determines that development warrants more restrictive control to provide for public health, safety, and welfare. For example, full access may be temporarily permitted at the eighth (1/8) mile when an arterial street is not yet improved to its ultimate profile.
(6) Access control — intersection hierarchy. The hierarchy of intersections shall be established in Table VI. Connecting street classifications that are more than one level above or below in the hierarchy shall be avoided unless the City Engineer and Planning Director determine that such connection is required due to topography, environmental sensitivity, or other condition as deemed appropriate by the City Engineer and Planning Director. Private access shall only be permitted to connect with local streets; provided, however, that shared private access may be permitted to higher classification streets upon the determination by the City Engineer that such connection is appropriate for public health, safety, and welfare.
F. Street jogs. Street jogs with center-line offsets of less than 150 feet shall be prohibited.
G. Cul-de-sacs. Cul-de-sacs shall be prohibited unless the City Engineer and Planning Director determine that a cul-de-sac is required due to topography, environmental sensitivity, geometry, or other condition as deemed appropriate by the City Engineer and Planning Director. Cul-de-sacs shall not be longer than 400 feet and shall be provided at the closed end with a turnaround having a diameter at the outside of the pavement of at least 75 feet, except such turnaround in industrial and commercial areas shall be 100 feet in diameter. The length of a cul-de-sac shall be measured from the centerline of the intersecting street to the center point of the closed end turnaround of the cul-de-sac.
H. Street names. Streets shall be named in a manner that is consistent with the naming conventions established for the Douglas-Sarpy County metropolitan area, including the numbering of north-south streets.
(1) Names in alignment. Proposed streets in alignment with existing streets shall bear the names of such existing streets.
(2) No duplication. The name of a proposed street that is not in alignment with an existing street shall not duplicate the name of any existing street within the Douglas-Sarpy County metropolitan area.
(3) Name change at curvature. Whenever a street alignment changes direction more than 60° without a return to the original alignment within a distance of 500 feet, the name of the street should be changed at the point of curvature.
(4) Cul-de-sac naming. A cul-de-sac street serving not more than four lots shall take the name of the intersecting street.
(5) Approval by the City Council required. The proposed names of all streets shall be subject to the approval of the City Council prior to such names being assigned or used.
(6) Similar sounding streets. Street names shall be easy to pronounce, spell, and read to reduce confusion. Similar sounding street names, although spelled differently, shall be avoided (Example: Lee and Leigh). In addition, the same street name should not be given a different or multiple street types (Example: "Main" should not be "Main Street" in some places and "Main Road" in other places).
(7) Vanity street names. Streets named after the subdivision shall be prohibited.
I. Horizontal and vertical street curves.
(1) A tangent of a length to be determined by the City Engineer shall be introduced between reverse curves on all streets. Where there is a deflection angle of more than 10° in the alignment of a street, a curve with a radius adequate to ensure safe sight distance shall be made.
(2) All vertical curves shall be designed to meet the American Association of State Highway and Transportation Officials (AASHTO) stopping sight distances/headlight distance required based on design speed.
J. Street grade and elevations.
(1) 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. The minimum street grade shall not be less than 0.7%. Streets that would be subject to inundation or flooding shall not be approved. Profiles or elevations of streets shall be furnished by the subdivider. Street grades shall conform to the minimum requirements provided in Table I of these regulations.
(2) Accessible crosswalks shall be identified, and street grades shall be adjusted accordingly to meet PROWAG requirements.
K. Private streets. There shall be no private streets platted within a subdivision.
L. Alleys.
(1) When required. Alleys may be required to give access to the rear of all lots used for commercial and industrial purposes. Alleys shall not be required in residential areas except in cases where the subdivider provides evidence of the need for alleys that is satisfactory to the City Council.
(2) Design. Alley intersections and sharp changes in alignment shall be avoided, but, where necessary, corners shall be cut off sufficiently to permit safe vehicular movement. Dead-end alleys shall be avoided where possible, but if unavoidable, shall be provided with adequate turnaround facilities and signage at the dead end, as determined by the City Council.
(3) Maintenance. Maintenance and snow removal of alleys shall not be the responsibility of the City.
M. Other right-of-way easements.
(1) Easements for utility rights-of-way shall be not less than five feet in width and whenever possible shall be provided along the rear and side property lines. See Table IV.
(2) When a subdivision is traversed by a watercourse, drainageway, channel, or stream, a stormwater easement or drainage right-of-way shall be provided with adequate width for both water flow and maintenance operations. The total width of any such easement shall be sufficient to accommodate a 100-year storm event, calculated for a fully developed upstream drainage basin. The minimum width of such easement shall be established by the Papillion Creek Watershed Management Policies and the Southern Sarpy Watershed Management Policies, as applicable. Parallel streets, parkways, walkways, or bridges may be required in connection with such drainage easement.
N. Outlots.
(1) Number minimized. The total number of outlots within a subdivision should be minimized to the greatest extent possible.
(2) Ownership of PCSMP outlots. At the time of platting, the subdivider shall be expressly identified as the owner of any outlot(s) being utilized for permanent post-construction stormwater management for a particular subdivision. Ownership of such outlot(s) may be transferred from the subdivider to a homeowners' or business owners' association for the subdivision once such entity is formed. Ownership of any such outlot(s) shall not be transferred to the City unless expressly authorized by resolution of the City Council.
(3) Ownership of outlots. At the time of platting, the subdivider shall be expressly identify ownership over all outlots. Ownership of any outlot(s) shall not be transferred to the City or sanitary and improvement district unless expressly authorized by resolution of the City Council.
(4) No buildings permitted. No buildings, other than those approved by resolution of the City Council, or otherwise allowed pursuant to a subdivision agreement between the City and subdivider, are permitted on outlots.
(5) Narrow outlots adjacent to public roadways prohibited. Narrow outlots adjacent to public roadways shall be prohibited. The subdivider shall extend private lots to the right-of-way. The subdivider may dedicate landscape easements within private lots if desired or incorporate the narrow outlots into public right-of-way as directed or authorized by the City Engineer and Planning Director.