A. 
Considerations. In considering an application for approval of the subdivision and/or development of land, the Board shall be guided by the standards set forth herein, which shall be deemed to be minimum requirements for the convenience, health, safety and welfare of the Village.
B. 
Character of land. Land to be subdivided and/or developed shall be of such character that it can be used safely for building purposes without danger to health or peril from fire, flood or other menace. Land subject to such hazards shall not be subdivided nor developed for residential purposes nor for such other uses as may increase the danger to health, life or property or aggravate a flood hazard, but such land may be set aside for such uses as shall not involve such danger nor produce unsatisfactory living conditions.
C. 
Conformance to Master Plan and Official Map. All subdivisions and developments shall conform to the Official Map and shall be properly related to the proposals shown on the Master Plan, if any. The plat shall include all streets shown on said map and plan, which are within the site and such other streets as the Board may require.
D. 
Frontage on improved street. The area proposed to be subdivided and/or developed shall have frontage on and direct access to a street duly placed on the Official Map, and if such street is private, it shall either be improved to the satisfaction of the Board or a performance bond pursuant to § 185-35 hereof covering such improvement shall be posted.
E. 
Preservation of natural cover. Land to be subdivided and/or developed shall be laid out and improved in reasonable conformity with existing topography, in order to minimize grading, cut and fill and to retain, insofar as possible, the natural contours, limit stormwater runoff and conserve the natural cover and soil. No topsoil, sand or gravel shall be removed from any lot shown on any subdivision plat, except for the purpose of improving such lot and for the laying out of streets shown thereon. Topsoil so removed shall be restored to a depth of six inches and properly seeded and fertilized on the areas of such lots not occupied by buildings or structures. No excess topsoil so removed shall be disposed of outside of the boundaries of the Village, except upon the approval of the Board of Trustees of the Village.
F. 
Preservation of existing natural features. Existing natural features that enhance the attractiveness of the site and which would add value to residential or other development or to the Village as a whole, such as trees, watercourses, ponds and similar irreplaceable assets, shall be preserved insofar as possible by harmonious design and careful development. The Board may make reasonable modifications in standards for layout of streets to accomplish such purposes as well as the objectives noted in Subsection E.
A. 
General. The arrangement, character, extent, width, grade and location of all streets shall conform to the Official Map and to the Master Plan, if any, and shall be considered in their relation to existing and planned streets, to existing topography and natural features, to public convenience and safety and in their appropriate relation to the proposed uses of the land to be served by such streets.
B. 
Relation to topography. Street layouts and grades shall be related appropriately to the existing topography, and streets shall be arranged to obtain as many as possible of the building sites at or above the grades of the streets. Steep grades shall be avoided as well as combinations of steep grades and curves.
C. 
New streets. Where proposed streets are not shown on the Official Map or the Master Plan, if any, such new streets, in addition to conforming to the Construction Standards and Specifications, shall be of sufficient width, suitably located and adequately constructed to accommodate the prospective traffic, to facilitate drainage and to afford access for fire-fighting, snow-removal and road-maintenance equipment. All streets shall be coordinated so as to compose a convenient system and to cause no undue hardship to adjoining properties.
D. 
Arrangement. The arrangement of streets shall provide for the continuation of principal streets between adjacent properties when such continuation is necessary for convenience, movement of traffic, effective fire protection or efficient provision of utilities and also where such continuation is in accordance with the Official Map or the Master Plan, if any. If the adjacent property is undeveloped and the street must be a dead-end street temporarily, the right-of-way shall be extended to the property line. A temporary circular turnaround shall be provided on all temporary dead-end streets, with the notation on the plat that land outside the normal street right-of-way shall revert to abutting owners whenever the street is continued.
E. 
Nonresidential streets. Whenever a street of an area to be subdivided is designated for professional, business or industrial use or for any use other than single-family residence, adequate provision shall be made for off-street loading and unloading and for off-street parking. Off-street parking facilities may, in the discretion of the Board, be required either on the street set apart for such nonresidential use or on an area of land adjoining such street. The Board may require that any parking area may be offered to the Village for dedication.
F. 
Intersections.
(1) 
Street jogs with center-line offsets of less than 125 feet shall not be permitted except with the approval of the Board.
(2) 
Intersections of streets shall be at angles as close to 90° as possible. Toward this end, an oblique street should be curved approaching an intersection and should be approximately at right angles for at least 100 feet therefrom. Where three or more streets intersect, a turning circle or other special treatment may be required by the Board. Wherever two streets intersect at an angle smaller than 75°, the right-of-way returns and the relation of the gutter grades shall be given special treatment, as determined by the Board, and islands to channelize traffic may be required.
(3) 
Intersections of major streets by other streets shall be at least 800 feet apart, if possible. Cross (four-cornered) street intersections shall be avoided insofar as possible except as shown on the Official Map or Master Plan, if any. A distance of at least 175 feet shall be maintained between center lines of offset intersecting streets. Grades shall be limited to no more than 2% within 50 feet of an intersection.
G. 
Treatment along major arterial streets. Where a subdivision abuts or contains an existing or proposed major street, the Board may require marginal access streets, reverse frontage with screen planting contained in a nonaccess reservation along the rear property line, deep lots with rear service alleys or such other treatment as may be necessary for adequate protection of residential properties and for separation of through and local traffic.
H. 
Provision for future resubdivision. Where a tract is subdivided into lots substantially larger than the minimum size required by the zoning,[1] the Board may require that streets and lots be laid out so as to permit future resubdivision in accordance with the requirements contained in this chapter.
[1]
Editor's Note: See Ch. 216, Zoning.
I. 
Dead-end streets.
(1) 
Where a street does not extend to the boundary of the subdivision and its continuation is not required by the Board for access to adjoining property, its terminus shall normally not be nearer to such boundary than 100 feet or the minimum lot depth prescribed by the zoning regulations,[2] whichever is greater. The Board may require the reservation of appropriate easements to accommodate future streets, drainage facilities, pedestrian traffic, utilities or other public purposes.
[2]
Editor's Note: See Ch. 216, Zoning.
(2) 
For greater convenience to traffic and more effective police and fire protection, permanent dead-end streets should, insofar as possible, be limited in length to 900 feet and shall be provided at the closed end with a turnaround having an outside roadway diameter of at least 80 feet and a street property line diameter of at least 100 feet. In zoning districts which permit lots of less than one acre, the minimum outside roadway diameter shall be increased to 120 feet.
(3) 
Where it is impossible to subdivide a property, except by a dead-end road which is longer than 900 feet, the Board may permit a greater length.
J. 
The following standards are adopted for all roadways constructed in the Incorporated Village of Old Westbury:
[Amended 2-23-1984 by L.L. No. 1-1984]
(1) 
Normal roadway design criteria.
(a) 
Streets:
[1] 
Minimum grade: 1.00% (0.70% in special cases, as determined by the Planning Board on recommendation of the Village Engineer.)
[2] 
Maximum grade: 10.0%.
[3] 
Width of road pavement: 24 feet for fifty-foot right-of-way.
[4] 
Maximum length of a dead-end street: 900 feet.
[5] 
Minimum property line radius, curvature in right-of-way: 200 feet.
(b) 
Culs-de-sac or turnaround areas:
[1] 
Minimum grade, all cases: 1.0%.
[2] 
Maximum grade: 3.0%.
[3] 
Property line radius: 60 feet (all cases).
[4] 
Gutter line radius: 47 feet (all cases).
[5] 
Provide curbed island in middle: radius = 17 feet, appropriately landscaped as approved.
(c) 
Intersections:
[1] 
Maximum grade: 2.5% (2.0% preferable).
[2] 
Provide triangular corners, right-of-way lines: thirty-foot isosceles triangle.
(d) 
Minimum sight distance, vertical curves: 300 feet.
(e) 
Minimum width, right-of-way: 50 feet.
(f) 
Curbing: concrete gutter, two feet wide.
(g) 
Minimum pavement requirements: 2 1/2 inches of asphalt (two lifts, the second lift to be applied not less than one year nor more than three years after the first lift is applied), five inches of dense graded stone mix or recycled concrete (total of 7 1/2 inches).
(2) 
Changes in grade. All changes in street grades shall be connected by vertical curves of sufficient radius to provide a smooth transition and proper sight distance, as approved by the Board.
(3) 
Tangents. A tangent at least 100 feet in length shall be introduced between reverse curves on all streets, except where a greater length is required by the Board.
(4) 
Curves. When the alignment of the street changes more than 10°, the tangents shall be connected by a curve with a radius of not less than 200 feet, unless a greater radius is required by the Board to ensure a proper sight distance.
(5) 
Reserve strips. Reserve strips controlling access to streets shall be prohibited, except where their control is placed in the Village under conditions approved by the Board.
(6) 
Property lines at intersections. Property lines at intersections shall be established in such a manner as to place, within the street right-of-way, the triangular area which is formed by the street lines extended and a straight line adjoining points on said street lines 30 feet distant from their point of intersection.
(7) 
Street names. All streets shall be named, and such names shall be approved by the Board. Names shall be sufficiently different in sound and in spelling from other street names in the Village or adjoining municipalities so as not to cause confusion. A street which is a continuation of an existing street shall bear the same name. In general, street names shall conform to the following classifications:
(a) 
Road: major or secondary street.
(b) 
Drive or lane: local residential street, except as follows:
[1] 
Court or place: permanent dead-end street.
[2] 
Circle: street that returns to its starting point or a street, both ends of which intersect another street at different locations.
A. 
Utilities. Easements across lots or centered on or adjacent to rear or side lot lines shall be provided for utilities where necessary and shall be at least 20 feet wide.
B. 
Drainageway. Where a subdivision contains or is traversed by a watercourse, channel or drainageway, as defined herein, there shall be provided a stormwater or drainage easement conforming substantially to the lines of such watercourse, channel or drainageway and including such further width or construction, or both, as shall be adequate for the purpose. The Board may require parallel streets or parkways in connection with such drainageway.
A. 
Dimensions and shape. The dimensions and shape of a block shall be determined with due regard to:
(1) 
Provisions of adequate building sites suitable to the special needs of the type of use contemplated.
(2) 
Zoning requirements as to lot sizes and dimensions.
(3) 
Needs for convenience access, circulation, control and safety of street traffic.
(4) 
Limitations and opportunities of topography and the objectives of these regulations.
B. 
Width. The width of a block shall be at least twice the minimum lot depth.
C. 
Long blocks. In long blocks the Board may require the establishment of easements or public ways through the block to accommodate utilities, drainage facilities or pedestrian access to community facilities.
A. 
General. The lots size, width, depth, shape and orientation and the minimum building setback lines shall be appropriate for the location of the subdivision and for the type of development and use contemplated. Lot shape shall be as nearly regular as is practicable.
B. 
Corner lots. Corner lots for residential use shall have extra width to permit compliance with the front yard setback from both streets.
C. 
Double lots. Where lots are more than double the minimum area required by the Zoning Ordinance,[1] the Board may require that such lots shall be of such dimensions and arrangement as will allow further subdivision and the opening of future streets where necessary to serve potential lots, all in compliance with the Zoning Ordinance and this chapter.
[1]
Editor's Note: See Ch. 216, Zoning.
D. 
Arrangement and access. The lot arrangement shall be such that there will be no foreseeable difficulty, for reasons of topography or other conditions, in obtaining building permits to build on all lots in compliance with applicable regulations and in providing, by means of a street approved by the Board and upon which each lot fronts, safe driveway access to buildings on such lots from an improved street duly placed on the Official Map.
E. 
Access across a watercourse. Where a watercourse separates the buildable area of a lot from the street by which it has access, provisions shall be made for installation of a culvert or other structure of design approved by the Engineer.
F. 
Lot lines and setbacks. Side lot lines shall be substantially at right angles to straight streets and radial to curved street lines. Lot lines shall coincide with municipal boundary lines rather than cross them. Where extra width has been dedicated for widening an existing street, lots shall begin at such extra width line, and lot dimensions and setbacks shall be measured from such line. The Board may, whenever it deems such lines desirable or necessary, require the showing on the plat of specific setback lines which may vary from lot to lot, provided that the front setback shall be not less than the zoning requirement.
G. 
Double frontage. Double frontage lots, other than corner lots, shall be avoided except where deemed essential by the Board in order to provide separation of residential development from traffic arteries or to overcome specific disadvantages of topography orientation. An easement or reserve strip, at least 20 feet in width and across which there shall be no right of access, shall be provided along the line of lots abutting such traffic artery or other disadvantageous use, and such easement shall be planted and maintained as may be approved by the Board.