(A) Purpose and Intent
The Conservation Residential Overlay District is established to implement the Comprehensive Plan. The goals and objectives of this overlay are to:
(1) Encourage environmentally sound planning;
(2) Protect open space and natural resources;
(3) Create attractive living environments;
(4) Encourage the creative placement of dwelling units;
(5) Limit the consumption of scenic, historic, and forested land for development;
(6) Design residential developments using natural topography, drainage ways and advanced water-quality protection techniques; and
(7) Create a contiguous network of open spaces by linking the open space areas within the residential development to open space on adjoining land wherever possible.
To further these goals and objectives, the overlay district provides the opportunity for residential developments to receive an increase in the number of potential dwelling units (based on the underlying zoning requirements) when such residential developments meet open space and other design requirements set forth within this Section.
(B) Location of District and Applicability
The provisions of the Conservation Residential Overlay District shall apply to the geographic areas designated as such on the Town of Cary Official Zoning Map. For properties designated as Conservation Residential on the Town of Cary Official Zoning Map and located outside of the Town's extraterritorial jurisdiction (ETJ), annexation and rezoning in accordance with this Section and all other applicable sections of the Land Development Ordinance is required before applicants may utilize the density bonus provisions of Sections 4.4.3(D) through (H).
This overlay district does not preclude any residential or non-residential uses allowed within the underlying zoning districts, provided that all applicable Land Development Ordinance requirements are met. Properties may be rezoned to residential or non-residential districts if supported by the Comprehensive Plan and in accordance with applicable sections of the Land Development Ordinance. Parcels zoned as Planned Development Districts and parcels subject to development plans approved before July 15, 2004, are exempt from the application of this Section for so long as the PDD or development plan remains valid.
The density bonus provisions of Sections 4.4.3(D) through (H) are optional. However, all development within the overlay district shall, in addition to all other requirements of the Land Development Ordinance, provide a buffer of fifty (50) feet in width along the American Tobacco Trail. The buffer shall function as visual separation between the public trail and private property; it shall contain native plant material, supplemented where necessary with deciduous and evergreen trees to provide an opaque screen for the benefit of trail users and adjoining property owners. The buffer shall conform to the requirements of a Type 'A' Buffer as described in LDO Section 7.2.3(D).
(C) Subdistricts Created and Defined
Due to the existing character and desired types of future development in the Conservation Residential Overlay District, differing residential densities, dimensional standards, open space requirements, and other related development standards are set forth within this Section. In order to present the full range of zoning and development requirements for each different area, this overlay zoning district is divided into two (2) subdistricts as follows:
(D) Eligibility and Process to Obtain Density Bonus
An increase in the number of lots (density bonus) above the number of lots that could be achieved utilizing the underlying zoning (base number of lots) is allowed, provided the development plan meets open space requirements and other design requirements set forth within this Section.
New residential developments within the Conservation Residential Overlay District seeking to utilize the density bonus provisions of this Section shall require submission of a development plan in accordance with Section 3.9 of this Ordinance, and approval of such plan by the appropriate decision-making body. To be eligible to gain additional units above the base number of lots, the minimum size of the site shall be ten (10) acres.
(1) Rezoning
For property located within the overlay district as shown on the Town of Cary Official Zoning Overlay Map, rezoning is not required in order to submit development plan applications that meet the requirements stated in Sections 4.4.3(D) through (H).
For properties within the Conservation Residential Overlay District but not within the Town Limits and/or Extraterritorial Zoning Jurisdiction (ETJ), annexation and rezoning is required before such properties can be developed pursuant to Sections 4.4.3(D) through (H). Annexation and rezoning (to establish initial zoning) to the Residential-40 district and Conservation Residential Overlay District must be approved before a proposed development plan using the provisions of Section 4.4.3(D) through (H) can be submitted for review.
Rezonings to non-residential and institutional uses may be permitted if consistent with the Comprehensive Plan. Rezonings to non-residential and institutional districts are not required to be subject to the requirements of this Overlay District.
(E) Calculating the Base Number of Lots
The base number of lots is defined as the lot yield based on the implementation of the requirements of the underlying zoning district. The base number of lots is the starting point from which extra lots may be permitted if non-regulatory or bonus open space, as defined below, is provided and other design requirements are met.
The applicant shall choose one (1) of the following methods for calculating the base number of lots:
(1) The base number of lots may be determined by taking ninety (90) percent of the potential developable area of the site and multiplying by the maximum density (based on lot area requirements) for the underlying zoning district. The purpose of reducing the potential developable acreage by ten (10) percent is to account for the approximate area that would be allocated to roadways within a conventional subdivision. "Potential developable area" within this Section is defined as the total land area of the site excluding all regulatory floodplains, streetscapes and other required areas (see Chapter 7: Development and Design Standards). For sites that contain and/or are adjacent to the American Tobacco Trail, a buffer of at least fifty (50) feet in width is required. This minimum buffer width is considered regulatory/required area, and shall not be included in the calculation of potential developable area.
Example: Site A
Total Site Acres: One hundred (100)
Acres in regulated/protected areas: Twenty (20)
Potential Developable Area Including Roadways: One hundred (100) - Twenty (20) = Eighty (80) Acres
Calculated Developable Area: Eighty (80) Acres x Ninety (90) percent = Seventy-two (72) Acres
Base Number of Lots: Seventy-two (72) Acres x 1.09 (density permitted in R-40) = Seventy-eight (78) lots
(2) The base number of lots may be determined based on the applicant providing a sketch development plan that fully complies with the development requirements of the underlying zoning district for the site.
(F) Increases to Base Density; Residential Use Type Allowed; and Minimum Dimensional Standards
(1) Increase in Density - An increase in the number of lots (density bonus) is provided in exchange for the permanent preservation of non-regulatory (referred to as "bonus") open space and compliance with other design requirements. An increase in the number of lots is achieved by allowing a smaller minimum lot size and increasing the permitted density (see Table 4.4-2 below).
(2) Allowance for Attached Dwelling Units - All lots developed in accordance with Sections 4.4.3(D) through (H) shall be for single-unit detached dwelling units with the exception of lots within the Conservation Residential Low Density (LCR) subdistrict. Within this subdistrict, attached, semi-detached, detached patio dwelling and townhome units shall be permitted, but shall not exceed twenty (20) percent of the total development yield. The lots for attached dwellings and detached patio dwellings shall use the Transitional Residential (TR) dimensional requirements, and therefore may have smaller lot sizes than the minimum lot size for detached lots as prescribed below.
(3) Specific Requirements by Subdistrict
Overlay Subdistrict | Maximum Development Density (d.u./acre) | Minimum Lot Size if Site Contains Less than Twenty (20) Percent of the Total Area in regulatory open space (sq. ft.) | Minimum Lot Size if Site Contains between Twenty (20) and Less than Thirty (30) Percent of the Total Area in regulatory open space (sq. ft.) | Minimum Lot Size if Site Contains Thirty (30) Percent or more of the Total Area in regulatory open space (sq. ft.) | Bonus Open Space Required Per Additional Lot |
Conservation Residential, Low Density (LCR) | 2.5 | 10,000 | 8,000 | 6,000 | 8,872 sq. ft. |
Conservation Residential, Very Low Density (VLCR) | 1.5 | 15,000 | 8,000 | 6,000 | 14,816 sq. ft. |
Notes:
Reduction in lot size due to twenty (20) percent or greater area in regulatory open space will be reduced incrementally until the maximum development density or minimum lot size is achieved, whichever occurs first.
The amount of bonus open space required is based on the following ratio:
In VLCR, a density bonus equal to three percent (3%) of the base number of lots is allowed for each one percent (1%) of bonus open space provided from the potential developable area of the site.
In LCR, a density bonus equal to five percent (5%) of the base number of lots is allowed for each one percent (1%) of bonus open space provided from the potential developable area of the site.
LCR Example (continued from 4.4.3(E)(1) above):
Size of Site | Base Number of Lots [see Section 4.4.3 (E)] | Bonus Open Space | Additional Lots (Density Bonus) | Gross Density (d.u./acre) |
100 Acres | 78 | 16 acres (20% of potential developable area) | 78 (100% more) | 1.6 |
100 Acres | 78 | 24 acres (30% of potential developable area) | 117 (150% more) | 2.0 |
(G) Bonus Open Space Requirements
All bonus open space provided must meet the following standards:
(1) Bonus open space shall be retained in a natural, undisturbed state, with the exception of those activities allowed by this Section. No more than five percent (5%) of the bonus open space area may be disturbed and allowed to be planted with grass or improved with other pervious ground cover in order to provide common informal gardens and/or play/open areas for the development or for the extension of main water and sewer lines. The five percent (5%) does not include disturbed areas due to the installation of required pedestrian systems (e.g., sidewalks, trails). However, active recreation facilities (e.g., basketball and tennis courts) are not permitted in the bonus open space used to obtain additional lots.
(2) In order to use the bonus density provisions of the Conservation Residential Overlay District, per part (F) of this Section, the subdivision must, at a minimum, provide an eighty (80) foot deep Type A opaque streetscape buffer along all of the subdivision's thoroughfare and collector road frontage. The amount of the eighty (80) foot deep streetscape buffer that is in excess of the amount of streetscape buffer normally required for a conventional subdivision under the requirements of Chapter 7 (See Section 7.2.4) qualifies as non-regulatory or bonus open space. Credit for bonus open space beyond a thirty (30) foot streetscape width may be allowed along thoroughfares that are designed as only two (2) lane roadways (similar to a collector roadway).
(3) Bonus open space shall be no less than thirty (30) feet in width at any point.
(4) Pedestrian access trails to the bonus open space areas shall be provided.
(5) No portion of the bonus open space shall be separated into non-contiguous segments smaller than thirty percent (30%) of the total bonus open space area. Open space divided by a roadway shall be defined as contiguous as well as open space adjacent to or across a roadway from regulatory stream and/or urban transition buffers.
(6) Credit for bonus open space may be provided for the preservation of contributing historic structure(s) within the Green Level National Register Historic District. This refers to the primary contributing structure on the site, such as the main farmhouse, as identified in the Green Level Historic District National Register Nomination document. The primary contributing structure must be located within a site containing at least one (1) acre of contiguous open space in order to better maintain the structure within its context in the landscape. Preservation is defined as the active restoration or rehabilitation and the ongoing maintenance of a structure. To qualify a primary contributing structure for the density bonus option, the property owner shall enter a preservation agreement with a qualified preservation organization. Preservation agreements may include, but are not limited to, historic preservation easements, facade and exterior covenants, or other methods acceptable to the Town.
The primary contributing structure within the Green Level National Register Historic District shall count as one (1) acre of bonus open space, provided that the structure is preserved and/or rehabilitated to the Secretary of the Interior's Standards for Rehabilitation. The primary structure must also be included within at least one (1) acre of bonus open space to preserve rural character features. This bonus open space may be used in a way that reflects the historic use of the property. If these requirements are met, a minimum of two (2) acres of open space may be credited to obtain bonus lots.
(7) The bonus open space shall be shown on the development plan, with a notation to indicate that the bonus open space shall not be used for future structures.
(8) The developer shall establish and incorporate a Homeowners' Association (HOA), which shall own the bonus open space and have the responsibility for maintaining the bonus open space and associated facilities at its own expense. An exception to the ownership of a portion of the bonus open space surrounding a contributing historic structure(s) within the Green Level National Register Historic District may be provided on a case by case basis. As an alternative to an HOA, a private, non-profit organization, whose primary purpose is open space conservation or preservation can own and manage the bonus open space.
(9) A portion or all of the bonus open space may be conveyed to the Town for use as greenways and parkland, provided it meets Town standards for such facilities and is agreed to by the Town. Such conveyance would occur at no cost to the Town.
(H) Additional Design Requirements
(1) Lot Dimensions
(a) For LCR lots, all dimensional requirements (i.e., setbacks, lot width) shall conform to R-8: Residential District standards with the exception of side yards. Side yards shall be a minimum of five (5) feet and an aggregate minimum of fifteen (15) feet. Residential lots less than eight thousand (8,000) square feet shall conform to TR: Transition Residential District standards.
(b) For VLCR, R-12 dimensional requirements shall be used for lots twelve thousand (12,000) square feet and greater in size. For lots between eleven thousand nine hundred ninety-nine (11,999) and eight thousand (8,000) square feet, R-8 dimensional requirements shall be used. For lots less than eight thousand (8,000) square feet, TR dimensional requirements shall be used.
(2) Where lots abut other residential lots within an existing subdivision that is not developed pursuant to Sections 4.4.3(D) through (H), said lots shall have a side and rear yard setback not less than the required side and rear yard setback required on the abutting property or the side and rear yard setback of the Residential 40 District.
(3) All streetscapes along thoroughfares and collectors shall be planted to a Type A standard.
(4) American Tobacco Trail (ATT) Buffer - A buffer of fifty (50) feet in width is required along the American Tobacco Trail. The buffer shall function as visual separation between the public trail and private property; it shall contain native plant material, supplemented where necessary with deciduous and evergreen trees to provide an opaque screen for the benefit of trail users and adjoining property owners. The buffer shall conform to the requirements of a Type 'A' Buffer as described in LDO Section 7.2.3(D). The fifty (50) foot wide buffer is not counted as bonus open space.
(5) No lot(s) shown on a development plan may be cleared or graded until the building permit for the lot is approved. Exceptions to this requirement may be considered based on factors related to the installation of roadways, public utilities or significant topographic issues. This exception must be approved by the Town based on written justification.
(6) Streets shall be designed and located as to preserve and maintain the natural topography and topographic features, as well as to minimize cut and fill practices.
(7) [Reserved]
(8) The requirements of Section 7.3, Stormwater Management, shall be achieved using LID site planning and techniques or a combination of LID and conventional stormwater management practices. The goal of LID is to develop site design techniques, strategies, and best management practices (BMPs) to store, infiltrate, evaporate, retain, and detain run-off on the site to more closely replicate pre-development run-off characteristics and to better mimic the natural and unique hydrology of the site thereby limiting the increase in pollutant loads caused by development. To the extent practical, stormwater shall be treated at its source through the use of small, non-structural BMPs and natural conveyance devices (swales, etc.). All BMPs shall be located in areas owned by the HOA or other entity (see 4.4.3(G)(8)) to ensure adequate maintenance. Structural BMPs may not be located in the bonus open space.
(9) Pedestrian Connectivity: A comprehensive pedestrian system shall be provided that makes the contiguous open space accessible to neighborhood residents and connects the open space to neighborhood streets. Limited pedestrian access shall be provided through Urban Transition Buffers and floodplain areas in accordance with the standards of this Ordinance.
Pedestrian connectivity shall be provided through an integrated combination of: primary trails, consisting of public sidewalks and greenways; and secondary trails consisting of private trails that provide connections within the development from public sidewalks and greenways to open space areas.
Public greenway trails shall be those depicted on the Parks, Recreation and Cultural Resources Facilities Master Plan. Such trails shall be ten (10) feet wide and constructed within a thirty (30) foot wide permanent Town of Cary greenway easement. The Town shall maintain all public greenway trails.
Secondary trails shall be constructed of asphalt, with a minimum width of eight (8) feet. Where feasible, secondary trails shall be located within Homeowners' Association (HOA) maintained common open space. In cases where this is not feasible, a twenty (20)-foot wide private pedestrian easement centered on these trails must be recorded and any required building setback shall be calculated from the outside boundary of the easement on the lot. All secondary trails shall be owned and maintained by the subdivision HOA and shall be available for public use.