A. 
Authority is hereby granted to the Planning Board pursuant to New York State Town Law § 278 to modify applicable provisions of Chapter 280, Zoning, of this Code, as to layout, configuration and design of lots, buildings and structures, roads, utility lines and other infrastructure, parks and landscaping, to enable and encourage flexibility of design and development of land in such manner as to preserve the natural and scenic qualities of open space lands. Any subdivision designed under this article shall indicate on the final plat that it is a cluster subdivision.
B. 
The Planning Board shall require cluster development of parcels seven acres or greater in size and not classified as a conservation subdivision. The Planning Board, at its discretion, may allow cluster development on any subdivision classified as a conservation subdivision, and may modify any provisions of this article in consideration of the ERSAP.
C. 
The Planning Board, at its discretion, may mandate cluster development of a parcel of seven acres or less in size in order to preserve the natural and scenic qualities of open lands. The Planning Board shall consider the ERSAP in making such a determination, and may require cluster development upon a finding that natural and scenic qualities of the parcel, including, but not limited to, the following should be preserved:
(1) 
Slopes: slopes of 15% or greater on 25% or more of the property.
(2) 
Land seaward of the coastal erosion hazard area line.
(3) 
Water resources: wetlands, aquifer and aquifer recharge areas, municipal water supply watershed areas, flood-prone areas as shown on Federal Emergency Management Agency maps, New York State protected areas, or areas legally protected by the County of Suffolk, the Town of Southold, private trusts or other entities or agencies.
(4) 
Agricultural lands: active farmland within a New York State certified Agricultural District, lands within 2,000 feet of a New York State certified Agricultural District, or soils classified in Groups 1 to 4 of the New York State Soil Classification System or areas legally protected by the County of Suffolk, the Town of Southold, private trusts or other entities or agencies.
(5) 
Community water and/or sewer: sites where community sewer, community water, or community water and sewer are available or planned.
(6) 
Critical environmental areas: lands within or contiguous to a critical environmental area designated pursuant to Article 8 of the Environmental Conservation Law.
(7) 
Designated open space areas: lands contiguous to publicly owned or designated open space areas, privately owned designated natural areas, or areas identified in the Southold Town Farm and Farmland Protection Strategy.
(8) 
Historic structures and sites: historic structures or areas of national, state or local importance.
(9) 
Scenic view sheds and special features: sites bordering designated state, county or Town scenic roads, or special features identified in the Town's Comprehensive Plan.
(10) 
Significant natural areas and features: areas with rare vegetation, significant habitats, or habitats of endangered, threatened or special concern species as determined by the New York Department of Environmental Conservation (Natural Heritage Program) or the Town Conservation Board, mature forests over 100 years old, locally important vegetation or unique natural or geological formations.
(11) 
Trails: existing and potential trails, bikeways, and pedestrian routes of Town, state or county significance.
(12) 
Recreation: lakes, ponds or other significant recreational areas, or opportunities or sites designated in the Town's Comprehensive Plan.
(13) 
Applicant request: on lands where the applicant has requested approval of a cluster development subdivision.
D. 
The Planning Board, at its discretion, may mandate cluster development in the AHD, RR, RO, LB, HB and B Zoning Districts for residential uses as permitted by this Code.
[Amended 1-20-2009 by L.L. No. 3-2009]
E. 
The Planning Board shall not increase the density permitted on the subject parcel as determined pursuant to § 240-10 of this chapter.
F. 
Where two or more properties are held in common ownership by the applicant(s) and the properties are adjacent or contiguous to one another, whether separated by a public or private street, utility easement or other such easement, the Planning Board may require clustering of the cumulative permissible yield onto one or more of the parcels.
G. 
Where two or more properties are held in common ownership by the applicant(s) and the properties are not adjacent or contiguous to one another, the Planning Board may require clustering of the cumulative permissible yield onto one or more of the parcels, subject to an approving resolution by the Town Board.
H. 
Design requirements for cluster development subdivisions. In addition to the other requirements of this chapter, the following shall apply:
[Amended 1-20-2009 by L.L. No. 3-2009]
(1) 
In the R-400, R-200, R-120, R-80 and R-40 and A-C Zoning Districts, a cluster development design must set aside a minimum of 60% of the buildable lands as open space lands.
(2) 
In the HD Zoning District, a cluster subdivision development must set aside a minimum percentage of buildable lands as shown in the column entitled "Open Space Set Aside" in the Schedule for Open Space, Buffers and Setbacks for Residential Site Plans at the end of Chapter 280.
(3) 
Utility and open space easements may be included in the calculation of the minimum required open space.
(4) 
Roads, streets and rights-of-way may not be included in the calculation of the minimum required open space.
A. 
The required open space land shall consist of a combination of primary conservation areas and secondary conservation areas as defined in § 240-3 and described in § 240-10C. The proposed design shall strictly minimize disturbance of these environmentally sensitive areas. The applicant shall demonstrate that such features will be protected by the proposed subdivision plan.
B. 
The location of open space lands shall be determined in general accordance with the goals of the Town's Comprehensive Plan and in particular with the Southold Town Farm and Farmland Protection Strategy to provide an interconnected network of open space and farmland.
C. 
Active agricultural land with farm/agricultural support buildings may be used to meet the minimum required open space land.
D. 
Open space land should generally remain undivided, except for roadway median strips, traffic islands, walkways, trails, courtyards, play areas, recreation facilities, drainageways, historic sites or unique natural features requiring common ownership protection.
E. 
No portion of any house lot as described in an existing or future deed may be used for meeting the minimum required open space land unless encumbered with a perpetual restriction preventing the development of such area in any way.
F. 
House lot standards. Development areas for the location of house lots include the necessary building envelope for each dwelling unit, constituting the remaining lands of the tract outside of the designated open space areas. House lots shall not encroach upon primary conservation areas, and their layout shall, where practical, respect secondary conservation areas. House lots shall be designed in accordance with the following standards:
(1) 
The buildable area of all proposed lots all shall meet the following setback requirements to the greatest extent practicable:
(a) 
From all external road rights-of-way, including New York State designated scenic byways (S.R. 25 and C.R. 48): 100 feet.
(b) 
From all other tract boundaries: 50 feet.
(c) 
From agricultural lands, either bordering or within the tract: 50 feet.
(d) 
From active recreation areas, such as courts or playing fields (not including small playgrounds for young children): 100 feet.
G. 
Views of house lots from exterior roads and abutting properties shall be minimized by the use of natural or landscaped buffers, changes in topography, existing vegetation, or additional landscaping in accordance with this chapter or other provisions of the Code.
H. 
House lots shall generally be accessed from interior streets, rather than from roads bordering the tract. New intersections with existing public roads shall be minimized. Two accessways into and out of subdivisions containing 10 or more dwellings are generally required for safety. Proposals for more than two entrances onto an arterial road, as defined herein, shall be discouraged if they would unnecessarily disrupt traffic flow or unduly impact the environment.
I. 
To the extent practical, the lots shall directly abut or face open space created under this chapter.
A. 
Ownership. As a condition of approval of a standard subdivision plat pursuant to this chapter and in order to further the Town's goals of permanent preservation, the Planning Board shall require that fee title to parcels of open space shown on the plat be conveyed to one or more of the following:
(1) 
The Town of Southold or other governmental unit or authority. The Town may, but shall not be required to, accept any portion of the open space land and common facilities, provided that:
(a) 
There is no substantial cost of acquisition to the Town; and
(b) 
The Town agrees to and has access to maintain such facilities; and
(c) 
Such facilities for public use shall be accessible to residents of the Town.
(2) 
Homeowners' association. Open space land and common facilities may only be conveyed to a homeowners' association if the following regulations are met:
(a) 
The applicant shall provide the Town with a description of the organization of the proposed association, including its bylaws, and all documents governing ownership, maintenance, and use restrictions for common facilities.
(b) 
The proposed association shall be established by the owner or applicant, and instruments which satisfy the requirements of this section must be recorded no later than the date on which the subdivision map is filed with the Suffolk County Clerk.
(c) 
Membership in the association shall be mandatory for each property owner within the subdivision and the owner's successors in interest, and each such owner must be required to pay a proportion of the annual cost of maintaining the open space or common areas.
(d) 
The association must have the power to levy assessments against each lot owner and which become a lien on the real property of any member who falls delinquent in his or her assessments.
(e) 
Written notice of any proposed transfer of common facilities by the association or the assumption of maintenance for common facilities must be given to all members of the association and to the Town no less than 30 days prior to such event.
(3) 
Noncommon private ownership. The required open space land may be included within one or more large agricultural reserve lots, provided the open space is permanently restricted from future development, except for those uses listed in § 240-44C. This option may be preferable for open space land that is intended for agricultural, horticultural, or silvicultural use.
(4) 
A private conservation corporation or land trust approved by the Planning Board, which is required under its charter to own and manage the open space in perpetuity for one or more of the purposes set forth in this chapter and which has the capacity to do so.
B. 
As a condition of approval of a conservation subdivision plat pursuant to this chapter and in order to further the Town's goals of permanent preservation, the Planning Board shall require that any required open space land resulting from clustering design shall be held in the same ownership of the other permanently preserved lands in the conservation subdivision.
C. 
Grant of restrictive easements required. Where fee title to open space created by cluster development as provided in this section will be conveyed, the Planning Board shall ensure that the open space is used in perpetuity only for the uses approved by the Board and shall ensure that public and record notice is given of the nature of the restrictions on the open space. To this end, the Planning Board shall:
(1) 
Require the grant of conservation easements, either to the Town of Southold or to an approved private conservation corporation or land trust, and require the filing of such other instruments as will permanently impose the open space restriction required by this chapter and give record notice of the same.
(2) 
Impose such other conditions and restrictions as will, in the discretion of the Board, ensure that the use of the open space is permanently restricted to those uses approved by the Board.
(3) 
All conservation easements required or agreed to by the Planning Board pursuant to this chapter shall be approved as to their form, content and manner of execution by counsel to the Planning Board or by the Town Attorney. Such easements shall be perpetual.
(4) 
All conservation easements, declarations or other instruments imposing or giving notice of restrictions on open space or other real property and required or agreed to by the Planning Board pursuant to this chapter shall be recorded in the office of the Suffolk County Clerk simultaneously with the filing of the subdivision map or development plat.
(5) 
No provision of this chapter shall be construed to supersede or modify any provision of a conservation easement previously granted to the Town of Southold so that the protection of open space which the easement affords is in any way diminished.
(6) 
Any person, firm, corporation or other entity shall have committed a violation of this chapter if said person, firm or corporation violates any provision of a conservation easement granted to or accepted by the Town pursuant to this chapter.
D. 
Restrictions on use. Use of open space shall be restricted and defined in a conservation easement, and shall be limited to the following:
(1) 
Conservation of open land in its natural state, including woodland, fallow field, or managed meadow. The clearing of woodland shall generally be prohibited, except as necessary to clear trails and active recreation facilities, remove invasive species, and to install subsurface sewage disposal systems. Fallow fields may be returned to agricultural production without penalty. The determination of necessity shall lie with the Planning Board and the Land Preservation Department.
(2) 
Agricultural and horticultural uses, including raising crops or livestock, wholesale nurseries, and associated buildings, that are specifically needed to support an active, viable agricultural or horticultural operation, subject to applicable lot coverage requirements in Chapter 280, Zoning, of this Code. Specifically excluded are concentrated animal feeding operations (CAFOs) as defined by the US Environmental Protection Agency, or commercial livestock operations involving swine, poultry, mink, ratites, and other animals likely to produce highly offensive odors. Such easement and a notation of the Town of Southold Farmland Bill of Rights shall be on the referenced final plat.
(3) 
Game preserve, wildlife sanctuary, or other similar conservation use.
(4) 
Woodlots, arboreta, and silviculture in keeping with established standards for selective harvesting and sustained yield forestry.
(5) 
Neighborhood open space uses, such as village greens, commons, picnic areas, community gardens, trails, and similar low-impact passive recreational uses specifically excluding motorized off-road vehicles, rifle ranges, and other uses similar in character and potential impact as determined by the Planning Board.
(6) 
Active noncommercial recreation areas, such as playing fields, playgrounds, and courts, provided such areas do not consume more than half of the minimum required open space land or five acres, whichever is less. Playing fields, playgrounds, and courts shall not be located within 150 feet of abutting properties nor shall such facilities be equipped with lighting. Parking facilities for the same shall also be permitted, and they shall generally be gravel-surfaced, unlighted, properly drained, provide safe ingress and egress, and contain no more than 10 parking spaces. Such recreation uses may be a public park or recreation area owned and operated by a public or private nonprofit agency, but shall not include storage of materials, trucking or repair facilities, or private or municipal sanitary landfills.
(7) 
Water supply and sewage disposal systems, and stormwater detention areas designed, landscaped, and available for use as an integral part of the open space area.
(a) 
Sanitary sewage disposal systems of either an individual or community nature may be located within or extend into required open space areas, provided that subsurface sewage disposal methods are employed, all required separation distances are observed and the ownership and maintenance responsibilities associated therewith are clearly defined in agreements submitted for approval as part of the subdivision application. No application shall be approved that does not provide property owners with both the legal authority and the responsibility, individually or collectively, to maintain all sewer facilities on a continuing basis. This may include the creation of a special district under Articles 12 and 12-A of New York State Town Law.
(b) 
Conservation of water. It is the requirement of the Planning Board to return stormwater to the ground within subdivisions. This is to be done through the use of natural recharge basins and/or leaching basins and/or lots specifically designated as drainage lots to be used for no other purpose. In addition, applicants shall be required to covenant that buildings and structures shall be equipped with leaders, gutters and dry wells to return stormwater runoff to the ground.
(8) 
Easements for drainage, access, sewer or water lines, or other public purposes.