BYLAW: Development Methods
DATE ADOPTED: July 1998
MUNICIPALITY: Amherst, MA
FOR MORE INFORMATION ON THIS BYLAW CONTACT:
Jonathan Tucker, Planning Director
4 Boltwood Ave
Amherst, MA 01002
PURPOSE OF BYLAW:
This Bylaw permits three (3) methods which may be utilized to develop land for residential purposes where such Uses are permitted in Section 3.3. The three methods are: Conventional Residential Subdivision Development;Cluster Development and;Planned Unit Residential Development (PURD)
TEXT OF THE BYLAW
SECTION 4.0 OVERVIEW This Bylaw permits three (3) methods which may be utilized to develop land for residential purposes where such Uses are permitted in Section 3.3. The three methods are:Conventional Residential Subdivision Development;
Cluster Development and;
Planned Unit Residential Development (PURD)In order to ensure development which is compatible with the Purposes and Intent of this Bylaw, the three Development Methods shall comply with the General Development Standards set forth is Section 4.1, and the applicable Standards set forth is Sections 4.32 and 4.42.The Zoning Districts in which the three Development Methods may be used are indicated in Table 2. Nonresidential zoning districts are not included in Table 2 because the three Development Methods described in this section apply only to residential development.
The abbreviations used in the Table are defined as follows:
Y = Yes The Development Method is permitted by right.
N = No The Development Method is not permitted in the zoning district.
SP = SPECIAL PERMIT The Development Method is permitted if a special permit is issued by the Board of Appeals.
SPP = SPECIAL PERMIT, The Development Method is permitted if a special
PLANNING BOARD permit is issued by the Planning Board.
TABLE 2 DEVELOPMENT METHODS
|4.2||CONVENTIONAL RESIDENTIAL SUBDIVISION DEVELOPMENT||Y||Y||Y||Y||Y||Y|
|4.4||PLANNED UNIT RESIDENTIALDEVELOPMENT||N||SP*||SP*||SP||SP||N|
SECTION 4.1 GENERAL DEVELOPMENT STANDARDS
The three Development Methods listed in Section 4.0, Overview, shall be undertaken in accordance with the following General Standards:
4.10 All Developments in the Town shall conform to the Design Standards and Required Improvements set forth in the Rules and Regulations Governing the Subdivision of Land and the Street and Site Work Construction Standards of the Town, as amended.
4.11 The frontage of lots shall be on existing or proposed minor or secondary streets as defined by the Amherst Planning Board's Rules and Regulations Governing the Subdivision of Land except as provided for in Section 4.4214.
SECTION 4.2 CONVENTIONAL RESIDENTIAL SUBDIVISION DEVELOPMENT
Conventional Residential Subdivision Development includes any subdivision of land, as defined in the General Laws, Chapter 41, to be developed for residential purposes.
SECTION 4.3 CLUSTER DEVELOPMENT
4.30 General Description
A "Cluster Development" shall mean a residential development in which the building and accessory uses are clustered together with reduced lot sizes, into one or more groups. The land not included in the building lots shall be permanently preserved as open space.
It is intended that a Cluster Development be developed as an entity by a landowner, or association of adjacent landowners, in which an alternative pattern of development may be permitted by which the following benefits are likely to be gained:
4.310 Economical and efficient street, utility, and public facility installation, construction, and maintenance.
4.311 Efficient allocation, distribution, and maintenance of common open space.
4.312 Land use harmonious with the natural features.
4.313 Compatibility with the character of the surrounding residential areas.
4.314 Efficient use of land to increase the options for affordable housing.
4.315 Housing development which allows for integration of a variety of housing types within one project.
4.316 Protection of natural resources, including but not limited to aquifers, wetlands and farmland.
4.32 Use and Dimensional Standards
4.320 A one-family detached dwelling, a zero lot line single family dwelling, a two-family detached dwelling (duplex), or attached dwellings, or other lawful accessory building may be constructed on certain lots in a Cluster Development (as herein defined and limited) although such lots have less area, frontage, and/or rear and side yard dimensions than normally required.
4.321 The total area of land included within the development shall be five (5) acres or more.
4.322 In all cluster developments, a minimum of 50 percent of the total lots shall be reduced at least 25 percent in area from the minimum standard lot size requirement of the zoning district in which the parcel is located.
4.3230 Unless otherwise provided for, the Dimensional Regulations of Table 3 shall be complied with.
4.3231 The maximum density of a cluster subdivision, except for an affordable cluster, shall not exceed the allowed density for a standard subdivision in any zoning district, said density to be calculated by taking the parcel area, subtracting 10% of that area and dividing that number by the minimum lot area of the zoning district in which the parcel is located. In addition, it is the intention of this Section that the cluster subdivision not result in more lots than would be approved for a standard subdivision under a Definitive Subdivision Plan.
4.3232 The Planning Board may reduce the frontage requirements for not more than 50 percent of the lots in the subdivision.
4.324 Zero lot line units are allowed in accordance with Section 4.320. A side yard need not be provided on that side of a dwelling unit that shares a party wall or double wall with an adjacent dwelling unit.
4.325 A minimum of 40% of the total dwelling units shall be single-family dwellings. A minimum of 20% of the total dwelling units shall be non-zero lot line, single family dwellings. A maximum of 60% of the dwelling units may be two-family dwellings. A maximum of 30% of the total dwelling units may be attached dwellings, There shall be no more that eight attached dwelling units allowed in one building.
4.326 The entire development shall be serviced with public sanitary sewer system, except in the ARP and WP districts associated with the Lawrence Swamp Aquifer, and in the FP District. In these districts, the Board of Health may, in accordance with state and local health regulations, authorize individual and/or shared septic systems in Cluster Developments where public sanitary sewer service is not reasonably available.
4.327 FP District In the FP District, dimensional regulations for Cluster Developments shall be as follows:
4.3270 The maximum number of building lots shall be calculated as follows:
1. Determine the Net Parcel Area by subtracting 50% of the area of all Unbuildable Land Area from the total parcel acreage. Unbuildable Land Area shall consist of the combined acreage of all wetlands, FPC District and 100-year floodplain areas. 100-year floodplain areas shall consist of those areas so identified on federal flood insurance maps.
2. Subtract 10 percent of the resulting Net Parcel Area for road allowance.
3. Divide the remaining 90 percent of the Net Parcel Area by the Basic Minimum Lot Area for the underlying zoning district. The resulting figure shall be the maximum number of building lots allowed in the Cluster Development.
4.3271 In the FP overlay district, the Basic Minimum Lot Area for the underlying zoning district shall be used only for determining the maximum number of building lots possible in a Cluster Development and for determining the amount of common land to be provided. Otherwise, all dimensional regulations for Cluster Developments in the FP District shall be the same as those specified in Table 3 for Cluster Developments in the R-N District, except as noted in Sections 4.3272 and 4.3273.
4.3272 In addition to the dimensional regulations specified in Table 3, Cpall be a maximum lot area for cluster lots as follows:
Cluster Maximum lot area 20,000 sq. ft.
Cluster flag lot max. 30,000 sq. ft.
4.3273 A 40 foot buffer zone of open space and/or common land shall be provided along any edge of the residential portion of a Cluster Development which abuts adjacent or on-site farmland. 4.33 Affordable Units4.330 The Planning Board may authorize a greater number of dwelling units than would be allowed by the density requirements of Section 4.3231 only if a minimum of 10% of the total units in the development are affordable units as herein defined. In no event shall the Board authorize a greater number of dwelling units than 120% of the maximum number of units otherwise allowed. For the purpose of this calculation, 10% of the total parcel size shall be subtracted for road allowance prior to calculating the maximum density normally allowed.
4.331 Attached units shall only be allowed in cluster developments that include affordable units.
4.332 For all cluster developments containing a minimum of 10% affordable units, the following Dimensional Regulations shall be substituted for those in Table 3.
4.333 Affordable housing units are those which may be rented or purchased by those who meet the guidelines for maximum annual income for a low-income or moderate-income family or household. The income limit for "low income" shall be 80% of the median income for Amherst, and the income limit for "moderate income" shall be 120% of median income for Amherst. Median income for Amherst will be as calculated by the U.S. Department of Housing and Urban Development, or any successor agency, and shall be adjusted for family size.
4.334 The applicant shall establish such restrictions, conditions, and/or limitations as are necessary to ensure that the units required for low-and moderate-income households will be permanently available for ownership, and available for a minimum of twenty years in the case of rental housing.
4.335 Housing constructed by a public agency or non-profit corporation using a federal, state, or local housing assistance program may adhere to the requirements set forth by the funding agency provided that the intent of these regulations are met.
4.336 Affordable housing units shall be geographically dispersed throughout the development.
4.34 Common Land Standards
The total area of Common Land shall equal or exceed the sum of the following: 4.340 The area by which all single-family dwelling lots are reduced below the basic minimum lot area normally required in the zoning districts.
4.341 The area by which all two-family dwelling lots are reduced below the minimum lot area normally required in the zoning districts for a two-family dwelling.
4.342 Projects that contain attached dwellings shall provide common land in accordance with the following formula: Subtract from the total parcel area the sum of a) and b), with a) being the area devoted to roads or rights-of-way and b) being the total area of all building lots. The remaining area shall be common land.
4.343 Land within the FPC District may be used to fulfill up to 60% of the Common Land requirements in Cluster Developments.
4.344 Within the common land provided in the Cluster Development, at least 2000 square feet per dwelling unit must be usable open space for active and passive recreation. Such space shall not include parking space, roadway, sidewalk area, land within the FPC District or Wetlands as determined by the Conservation Commission. Usable open space shall be defined to include such facilities as contiguous open space available for play, tot lots, gardens, hiking/jogging trails, tennis courts, or similar facilities.
4.345 In the FP District, all common land in a cluster development not set aside as usable open space for active and/or passive recreation shall be permanently preserved as farmland.
4.35 Common Land Ownership
4.350 All common land hereunder shall either (1) be conveyed to the Town of Amherst and be accepted by it for park or open space use, or (2) be conveyed to a non-profit organization, the principal purpose of which is the conservation of open space, (3) be conveyed to a corporation or trust owned or to be owned by the owners of the lots or residential units within the development, or (4) be conveyed to a private, non-profit or public entity for the purposes of farming, with a restriction enforceable by the Town of Amherst being recorded which provides that such land shall either be actively farmed or kept in an open and natural state, If such a corporation or trust is utilized, as indicated herein, ownership thereof shall pass with conveyances of the lots or residential units. Under the second and third ownership alternatives listed above, a restriction enforceable by the Town of Amherst shall be recorded providing that such land shall be kept in an open or natural state and not be built upon for residential use or developed for accessory uses such as parking or roadway.
4.351 In the FP District, that portion of the common land which is set aside as permanently preserved farmland and all Unbuildable Land Area shall be protected by a permanent agricultural preservation restriction recorded on the deed. Title to this permanently restricted farmland may remain with the original farmland owner or be conveyed to the Town of Amherst, the Commonwealth of Massachusetts, a homeowners' association, or a non-profit farmland trust or similar conservation organization whose principal purposes include the preservation of farmland. The agricultural restriction recorded on the deed shall be enforceable by the Town of Amherst. It shall be kept as active farmland or kept in an open or natural state for future farming uses, and shall not be built upon for residential use or developed for accessory uses such as parking or roadway.
4.352 The location, size, and shape of common land shall be subject to the approval of the Planning Board if such land is to be conveyed to the Town.
4.36 Review and Approval Process
4.360 Approval will be by Special Permit by the Planning Board, in accordance with the standards set forth in Section 10.3, with the purposes of Cluster Development as set forth in Section 4.31 of the Zoning Bylaw and with the design requirements of Section 4.38.
4.361 Subsequent approval by the Planning Board of such portions of the Cluster Development as constitute a subdivision shall be required as set forth in the Subdivision Control Law, including approval of the streets and utility system. A favorable action which may be made by the Planning Board on a Special Permit application shall not, therefore, be deemed either to constitute subdivision approval under the Subdivision Control Law or Rules and Regulations Governing the Subdivision of Land, nor imply that such approval will be given.
4.37 Flood-Prone Conservancy
Each application for a Cluster Development containing land within the Flood-Prone Conservancy district shall be accompanied by an additional set of plans and documents. Within ten days after receipt of the application the Planning Board shall transmit a copy thereof to the Conservation Commission which said Commission may, in its discretion, investigate the proposed development and report in writing its recommendation to the Board. The Planning Board shall not take final action on approval until it has received a report thereon from the Conservation Commission or until said Commission has allowed 35 days to elapse after receipt of such application without submission of a report.
4.38 Cluster Development Design Requirements
4.380 Vehicular and Pedestrian Circulation: primary routes shall be clearly differentiated from secondary routes and driveways; conflicts shall be minimized between vehicular routes and pedestrian routes and recreation areas.
4.381 Screening and Buffers: layout and design shall respond to needs for privacy between and around dwelling units; no structures shall be placed closer to the project property line than the front setback requirement for that zoning district.
4.382 Common Land: the majority of the common land shall consist of large blocks of contiguous areas easily accessible to most residents of the development from streets, cul-de-sacs and other open areas and links between different sections of common land shall be clearly shown; physical and visual access to the common land from the dwelling units shall be maximized, the preservation of the original landform and existing vegetation shall be maximized.
4.383 Utilities and Services: dumpsters shall be located in convenient locations, visually screened, and shall not impede pedestrian or vehicular circulation; the installation and location of drainage systems shall not impede access to common land.
4.384 Protection of Environmentally Sensitive Areas: the Board may reduce the number of lots otherwise allowed for the protection of aquifers, wetlands, or other environmentally sensitive areas.
4.385 Building Siting: the Planning Board may review and approve the sites of all buildings, structures, driveways and parking areas for each lot and may establish building envelopes for all buildings within a cluster subdivision.
SECTION 4.4 PLANNED UNIT RESIDENTIAL DEVELOPMENT
4.40 General Description
Planned Unit Residential Development shall mean a mixed use development on a plot of land containing a minimum of 134,500 square feet in which a mixture of residential, open space, and such other uses, and a variety of building types, as may be permitted hereunder which are determined to be sufficiently advantageous to render it appropriate to grant special permission to depart from the normal requirements of the district to the extent authorized by this Bylaw.
It is intended that a Planned Unit Residential Development be a subdivision to be developed as an entity by a landowner which does not correspond in lot size, bulk or type of dwelling, density, intensity of development, or required open space to the regulations in any one other district established by this Zoning Bylaw. The major purpose of the Planned Unit Residential Development, in addition to the purposes governing this Bylaw as stated in Article 1, is to provide for a mixture of housing types at certain locations and in certain districts in the Town at a greater density than would normally be allowed in each district without detracting from the livability and aesthetic qualities of the environment. A Planned Unit Residential Development should result in: 4.410 Economical and efficient street, utility, and public facility installation, construction, and maintenance,
4.411 A variety of housing types and characteristics appropriate to various social and economic groups,
4.412 Efficient allocation, distribution, and maintenance of common open space,
4.413 Land use harmonious with the natural features and,
4.414 The development of real property values for the long range future.4.42 Use and Dimensional Standards
4.420 In a Planned Unit Residential Development the following uses shall be permitted:
4.4200 One-family dwelling
4.4201 Two-family or semi-detached dwelling
4.4203 Multiple-family dwelling
4.4204 Nursery or Kindergarten
4.4205 Place of worship
4.4206 Public educational use
4.4207 Governmental use
4.421 In a Planned Unit Residential Development the following requirements relating to the density and intensity of land use shall be met:
4.4210 Separate lots for single family dwellings shall be permitted, but are not required. If provided, the lot area shall be three quarters of the minimum lot area required for the applicable Zoning District in Table 3. If not provided, the same calculation shall be used per lot to determine the maximum density allowed for the single family units.
4.4211 Separate lots for duplex dwelling units shall be permitted, but are not required. If provided, the lot area shall be three-quarters of the minimum lot area, plus the additional minimum area per family required for the applicable Zoning District. If not provided, the same calculation shall be used per lot to determine the maximum density allowed for the duplex dwelling units.
4.4212 Separate lots for townhouses shall be permitted but are not required. If provided, the lot area for each unit shall be not less than two times the footprint of the unit, and shall include the area of the footprint of the unit. In no case shall any property line of the lot extend further from the unit than a distance in linear feet, that is numerically equivalent to 10% of the area, in square feet, of the footprint of the unit.
x = Footprint of the townhouse
y = Lot area (2x) of the townhouse (includes footprint)
z = Distance of lot line from the townhouse (maximum 10%, in linear foot equivalent, of the area of the townhouse footprint)
4.4213 For townhouses, with or without separate lots, and for multi-family units, two times the minimum additional lot area per family for the applicable Zoning District shall be used to calculate the maximum density allowed in the PURD for these units.
4.4214 There shall be no frontage requirements in the PURD.
4.4215 Maximum height of structures: as regulated in Table 3.
4.4216 Minimum setback and rear/side yards pertaining only to the periphery of the Planned Unit Residential Development: equal to the requirements in each district as shown in Table 3. If separate full size lots are created, the minimum setback and side yards shown in Table 3 for the applicable Zoning District shall be provided. Dimensional regulations for all undersized single family and two family lots shall conform to the required regulations for the R-G District found in Table 3.
4.4217 Within the open space area provided in the PURD, at least 1,000 square feet per dwelling unit must be usable open space for active and passive recreation. Such space shall not include parking space, laundry drying area, required yards, land within the FPC District or Wetlands as determined by the Conservation Commission. Usable open space shall be defined to include such facilities as contiguous open space available for play, tot lots, gardens, hiking/jogging trails, tennis courts, or similar facilities.
4.4218 Maximum percentage of dwelling units of any one type of permitted housing: 75%.
4.4219 Minimum parking requirements: as regulated in Article 7 of this By-Law.
4.4220 Not more than fifty percent of land within the FPC District and wetlands as determined by the Conservation Commission shall be used to fulfill the density requirements for the PURD notwithstanding Section 6.4.
4.43 Common Land Ownership
Open space or common land shall be assured and maintained in accordance with the procedures prescribed in Section 4.35 of this Bylaw.
4.44 Review and Approval Process
In addition to the requirements specified in Section 10.3, Special Permit, of this Bylaw and Section 9, Chapter 40A of the General Laws, the following procedures shall be required for the presentation of a Planned Unit Residential Development plan: 4.440 The proposed development shall be in harmony with the Master Plan of the community, if any, as prepared and amended by the Planning Board.
4.441 The development plan shall specify reasonable periods within which development of each section of the Planned Unit Residential Development may be started. Deviation from the required amount of usable open space per housing unit may be allowed, provided such deviation shall be adjusted for in other sections of the Planned Unit Residential Development.
4.442 Subsequent approval by the Planning Board of such portions of the development as constitute a subdivision will be required as set forth in the Subdivision Control Law, including approval of the street and utility systems. A favorable recommendation by the Planning Board that the Special Permit be issued shall not, therefore, be deemed to either constitute subdivision approval under the Subdivision Control Law or the Subdivision Rules and Regulations of the Planning Board, nor imply that such approval will be given.
4.45 Flood Prone-Conservancy
Each application for a PURD containing land zoned Flood Prone-Conservancy shall be accompanied by an additional set of plans. Within ten days after receipt of the plan, the Board of Appeals shall transmit a copy thereof to the Conservation Commission, which said Commission may, in its discretion, investigate the proposed development and report in writing its recommendations to the Board of Appeals. 4.46 The Board of Appeals shall not take final action on application for a Special Permit hereunder until it has received a report thereon from both the Planning Board and Conservation Commission, or until said Planning Board and Conservation Commission have allowed 35 days to elapse after receipt of such plan without submission of a report.