ZONINGPRACTICE August 2007 AMERICAN PLANNING ASSOCIATION

ISSUE NUMBER EIGHT PRACTICE CLUSTER DEVELOPMENT 8 Cluster Development: Modern Application of an Old Town Form By Stuart Meck, FAICP

Residential cluster development is a form of land development in which principal and structures are grouped together on a site, thus saving the remaining land area for com- mon open space, conservation, agriculture, recreation, and public and semipublic uses.

(Left) “Yield plans” to determine density: Under Pennsylvania’s Growing Greener program, conventional yield plans like this, demonstrating the feasibility of 18 two-acre lots in the two acre-district, are no longer allowed. (Right) Village design under Growing Greener is an alternative option. It illustrates how lot yield could be dou- bled as a strong incentive for developers to produce layouts following certain hamlet design principles, including 70 percent of the unconstrained land remaining as permanent open space.

All images by Randall Arendt. Adapted from PAS Report 523/524: Crossroads, Hamlet, Village, Town: Design Characteristics of Traditional Neighborhoods, Old and New; revised edition, 2004.

In many respects, cluster development dates development. A well-planned cluster develop- activity centers, residents of the cluster devel- back to one of the earliest town forms. In ment concentrates dwelling units on the most opment may walk and exercise more. primitive early settlements, dwelling units buildable portion of the site and preserves natu- Clustering also enhances the sense of were often organized to form a common area ral drainage systems, vegetation, open space, community, allowing parents better supervision or enclosure that residents could use together and other significant natural features that help of children playing in common areas and pro- and readily defend if necessary. control stormwater runoff and soil erosion. moting social interaction among neighbors. In the United States, the 1928 develop- The common areas function as a trap for The model ordinance featured in this ment of Radburn, New Jersey, represented the nutrients dissolved or suspended in stormwater issue of Practice is intended to first formal introduction of the cluster devel- runoff. Cost savings during are encourage developers to use cluster devel- opment concept. It drew on English town plan- achieved by the reduction in street lengths and opment as an alternative to conventional ning principles, notably those of the Garden utility installations. Later savings can be realized lot-by-lot development, and authorizes clus- movement. In Radburn, single-family in street and utility maintenance (less surface ter development as of right either in all resi- homes and garden are sited in area that needs repaving and fewer feet of water dential districts or in selected ones. Section “superblocks” of 35 to 50 acres. The super- and sewer line to maintain). Because dwelling 110 of the ordinance (see page 7) also offers blocks have no through traffic and are inter- units are placed closer together, refuse and density bonuses of up to 25 percent when a spersed with and related green spaces other service vehicles do not have to negotiate developer: (a) provides affordable housing on which the residences face. Clustering also over as much street mileage, thus reducing as part of the cluster development (thereby became the basic site design concept in such travel time. helping the local government achieve hous- contemporary new towns as Reston, Virginia, Where clustering is accompanied by ing goals that may have been established by and Columbia, Maryland. higher-density residential land uses and the the state) and (b) conveys land for open Cluster development has a number of dis- provision of pedestrian pathways and bike- space, recreation, or other purposes that is tinct advantages over conventional ways, especially those that link to off-site accessible to the public.

ZONINGPRACTICE 8.07 AMERICAN PLANNING ASSOCIATION | page 2 Under Section 107 of the model (see page 6), the local planning commission has the primary responsibility for reviewing and approving a cluster development, although such a function could also be assigned to a hearing examiner. The model ordinance sets forth criteria for the commission to apply in deciding whether to approve the cluster development. (Remember that the responsibilities of the local planning commission vary from state to state.) The model does not include a severabil- ity clause because it assumed this ordinance will be incorporated into a zoning code that will have one already. This model is based on a sample ordi- nance appearing in Nonpoint Source Pollution: A Handbook for Local Governments by Sanjay Jeer, Megan Lewis, Stuart Meck, Jon Homes fronting directly onto parks: A view showing the direct relationship beween houselots and Witten, and Michelle Zimet, Planning Advisory the formal open space. These lots have no street frontage and are accessed only by foot from the Service Report No. 476 (Chicago: American front, with driveways leading to rear service lanes. These homes possess greater “curb appeal” Planning Association, 1997). Local policy mak- than similar fronting onto curbs and streets. ers, such as mayors, council members, and planning commissioners, can use this ordinances and get into the details of drafting (c) decrease or minimize nonpoint source pol- article to familiarize themselves with the con- and administering one for cluster develop- lution impacts by reducing the amount of tents of land development regulations, alter- impervious surfaces in site development; ments. The primary principle native ways to update such regulations, meth- addressed with cluster development is the (d) promote cost savings in infrastructure ods to incorporate smart growth objectives, installation and maintenance by such tech- preservation of open space and farmland. and types of smart growth ordinances. niques as reducing the distance over which Secondary smart growth principles include The model cluster development ordi- utilities, such as water and sewer lines, need creating distinctive and attractive places. to be extended or by reducing the width or nance provides a starting point for discussion Model provisions are followed by com- length of streets; and among policy makers as to the desirability mentary and remarks concerning the locally (e) provide opportunities for social interac- and general approach to such regulations. In adopted ordinances used as a basis for draft- tion and walking and hiking in open space some cases, the model ordinance provides areas. ing them. several regulatory alternatives among which policy makers can select or, by working with Remember to consult your state statutes THE MODEL TOWN CENTER ORDINANCE their planners, devise a hybrid approach that to employ definitions that are consistent with WITH COMMENTARY suits their community. 101. Purpose those statutes. These definitions were drawn Professional planners can use the (1) It is the purpose of this ordinance to permit from different sources and, while useful, may options discussed in the article to help policy residential cluster development in order to: differ from those already established by your makers understand land development regula- (a) encourage creative and flexible site design state legislation. Definitions of “affordable,” tion and how to meet smart growth objectives that is sensitive to the land’s natural features “low-income household,” and “moderate- and adapts to the natural topography; in the formulation of a town center ordinance. income household” may need to be changed The article contains enough model language (b) protect environmentally sensitive areas of to comply with current requirements of the a development site and preserve on a perma- for planners to understand the technical and nent basis open space, natural features, and applicable federal or state construction or administrative complexities of smart growth prime agricultural lands; rehabilitation program. In particular, the

THE MODEL CLUSTER DEVELOPMENT ORDINANCE This issue of Zoning Practice provides an overview of the structure of cluster development regulations and is part of a larger effort by the American Planning Association on the development of model smart growth ordinances. The original report was prepared under the direction of APA’s research department in Chicago. Stuart Meck, FAICP, was the principal investigator and coauthor. He is the director of the Center for Government Services in the Edward J. Bloustein School of Planning and Public Policy at Rutgers University. Coauthor Marya Morris, AICP, a former APA senior research associ- ate, is now a senior associate with Duncan Associates in Chicago. Rebecca Retzlaff, AICP, assistant professor in Auburn University’s community plan- ning program, assisted the authors. Other coauthors include Kirk Bishop, executive vice president of Duncan Associates, Chicago, and Eric Damian Kelly, vice president of Duncan Associates and a professor of planning at Ball State University in Muncie, Indiana. The editor was James Hecimovich, the editor of APA’s Planning Advisory Service. Lisa Barton, design associate, designed the report. William R. Klein, AICP, APA’s director of research, provided overall project administration.

ZONINGPRACTICE 8.07 AMERICAN PLANNING ASSOCIATION | page 3 bracketed percentages may be modified to limited to, reduction in lot areas, setback recreational, open space, and or/mixed uses affect the scope of the definition. requirements, and bulk requirements, with the as are provided for in the zoning ordinance. resultant open space being devoted by deed Lot means either: (a) the basic development unit 102. Definitions restrictions for one or more uses. for determination of area, depth, and other As used in this ordinance, the following words Cluster development, residential refers to a land dimensional variations; or (b) a parcel of land and terms shall have the meanings specified development project in which the site planning whose boundaries have been established by herein: technique of clustering dwelling units is some legal instrument, such as a recorded deed Affordable means either a sales price that is within employed. or map, and recognized as a separate legal the means of a moderate-income household or a Common open space is the portion of the site entity for purposes of transfer of title. rental amount for housing that is within the means set aside in perpetuity as open space. This area Low-income household is one whose gross of a low-income household, as those terms are may include coastal and freshwater wetlands, annual income does not exceed [50] percent of defined in this Section. In the case of dwelling floodplains or flood-hazard areas, stream corri- the area median as adjusted for household size. units for sale, housing that is affordable is housing dors, prime agricultural lands, habitats of for which the mortgage, taxes, insurance, and fees Moderate-income household means a - endangered wildlife as identified on applicable hold whose gross annual income is less than are no more than [30] percent of the adjusted federal or state lists, scenic views, historical or income for a household whose gross annual [80] percent of the area median as adjusted for cultural features, archaeological sites, or other household size. income is at or below [80] percent of the median elements to be protected from development, as for the area based on household size. In the case well as easements for public utilities. Net buildable area means the portion of the of rental housing, housing that is affordable is cluster development that may be developed or used for common open space, whether publicly dedicated or private, but excluding private streets, public streets, and other publicly dedi- cated improvements. Site plan means the development plan for one or more lots on which is shown the existing and the proposed conditions of the lot. Street, private is a local roadway serving only abut- ting lots, not publicly dedicated or maintained by the [local government] but meeting specific munic- ipal improvement standards and providing access for service and emergency vehicles. Street, public means all public property reserved or dedicated for street traffic.

(Above) A typical green at Chatham Village in Pittsburgh. Occupying the highest ground on this hilltop site, it is framed by buildings that are two stories high in front and three in the back, with garages on the lowest level. (Right) Homes in Chatham Village are accessed from the rear via a loop road, and face each other across smaller and more formal greens.

housing for which the monthly rental amount plus Development means the construction, recon- Structure means anything constructed or utility costs do not exceed [30] percent of the struction, conversion, structural alteration, relo- erected that requires location on the ground or adjusted income for a household whose gross cation, or enlargement of any structure; any attached to something having location on the income is [50] percent of the area median house- mine, excavation, landfill or land disturbance; ground. hold income adjusted for household size. and/or any change in use, or alteration or exten- Buffer is land maintained in either a natural or sion of the use, of land. There is a fair degree of debate about landscaped state and used to screen or mitigate Gross area is the total area of the site, includ- whether the area of a cluster development the impacts of development on surrounding ing the net buildable area and public rights-of- should be limited. Because cluster develop- areas, properties, or rights-of-way. way. ment is fundamentally a design review means any structure used or intended for Infrastructure refers to the facilities and services process, in theory the approach should be supporting or sheltering any use or occupancy. needed to sustain residential, commercial, applicable to a site of any size. However, it Cluster (or Clustering) is a site-planning tech- industrial, institutional, and other activities. nique that concentrates buildings and structures Land development project means a project in may be that, for smaller sites, a cluster devel- in specific areas on a lot, site, or parcel to allow which one or more lots, tracts, or parcels of opment may not yield any appreciable bene- the remaining land to be used for recreation, land are to be developed or redeveloped as a fits over conventional subdivisions. Conse - open space, or preservation of features or struc- coordinated site for a complex of uses, units, quently, the decision to authorize cluster tures with environmental, historical, cultural, or or structures, including, but not limited to, other significance. The techniques used to con- planned development and/or cluster develop- development will depend on the policy prefer- centrate buildings may include, but shall not be ment for residential, commercial, institutional, ences of the individual local government.

ZONINGPRACTICE 8.07 AMERICAN PLANNING ASSOCIATION | page 4 103. Applicability; General Provisions cent of such floodplains and/or wetlands shall (h) The location of sidewalks, trails, and bike (1) A residential cluster development shall be per- be included in calculating the common open paths mitted [as of right in any residential zoning district space.] (i) The number of acres that are proposed to pursuant to this ordinance or as of right in the fol- be conveyed as common open space lowing zoning districts: list district names]: Uses other than residences may be (j) [Cite any other plans or information other- (a) All principal and accessory uses author- located on the site. For example, the cluster wise required by the local government for a ized in the applicable residential zoning dis- major land development or subdivision in its development may include storage facilities, trict(s) shall be allowed in the cluster devel- land development or subdivision regulations, opment. In addition, multifamily dwellings, garages, and recreational buildings. Conceiv- such as a plan for landscaping and screening.] duplexes, and town houses may be permitted ably, a very large cluster development could The calculations in Section 105 (2) below for a cluster development located in a resi- also include sites for schools. dential zoning district that does not other- are intended to mirror those that a local govern- wise allow attached dwelling units. 104. Contents of Site Plan ment would normally employ for determining (1) The preliminary and final site plan for a residen- (b) Maximum lot coverage, floor area ratios, the maximum number of dwelling units permit- building height, and parking requirements for tial cluster development shall include, but shall ted for nonclustered development. Some com- the applicable zoning district shall apply to not be limited to, the following information: the cluster development. Maximum lot cover- (a) The maximum number and type of munities may subtract from the gross area of the age, floor area ratios, and parking require- dwelling units proposed cluster development land area in wetlands and ments, however, shall be applied to the entire site rather than to any individual lot.

(2) The following provisions shall apply to any residential cluster development, regardless of the general requirements of the applicable resi- dential zoning district: (a) The minimum area of the cluster develop- ment shall be [two to five] acres.

In some states, the identification of flood- plains and coastal or freshwater wetlands occurs routinely as part of the land develop- ment and subdivision review process. Optional language in Section 103(2)(g) above requires that at least 50 percent of the floodplains and This axonometric wetlands must be included as part of the com- view illustrates the mon open space. By including the land desig- relationship between nated as common open space, the calculation homes, yards, streets, and of net buildable area gives credit for the land alleys in a way that ensures area in which floodplains and wetlands that backyard privacy even at higher meet state criteria are located. This is intended building densities—a feature to serve as an incentive to employ clustering by not uncommon with cluster allowing the area represented by lands in flood- developments. plains and wetlands to be used in determining the maximum number of dwelling units. (b) The areas of the site on which the dwelling floodplains, which will reduce the maximum units are to be constructed or are currently (b) No minimum width or depth of a lot shall number of dwelling units in the development. located and their size (this may take the form of apply. the footprint of the dwelling unit or a building 105. Calculation of Permitted Number of Dwelling (c) A minimum separation of [10] feet shall be envelope showing the general area in which Units; Density Bonuses provided between all principal buildings and the dwelling unit is to be located). (1) Except as provided in paragraph (3) below, structures. (c) The calculations for the permitted number the maximum numbers of dwelling units pro- (d) A minimum yard or common open space of dwelling units, derived pursuant to Section posed for a residential cluster development shall of a least [25] feet in depth shall be provided, [105] not exceed the number of dwelling units other- as measured from all public streets and from wise permitted for the residential zoning district (d) The areas of the site on which other pro- the side and rear lot lines of the entire cluster in which the parcel is located. posed principal and accessory uses may be development. located and their size (2) Except as provided in paragraph (3) below, (e) Each lot shall have a minimum access of the number of permitted dwelling units on a site [12] feet to a public or private street. Such This model assumes the local govern- shall be calculated in the following manner: access may be shared with other lots. ment will require sidewalks as part of the (a) Measure the gross area of the proposed (f) More than one principal building or struc- public improvements required for subdivision. cluster development site in acres and tenths of ture may be placed on a lot. (e) The areas of the site designated for com- an acre. (g) Not less than [25] percent of the site shall mon open space and their size (b) Subtract from the gross area determined be conveyed as common open space in the (f) The areas of the site designated for parking in subparagraph (a) the area of public and manner provided for in Section [110]. [Where and loading and the size of individual spaces private streets and other publicly dedicated the site contains floodplains and/or coastal or (g) The number and percentage of dwelling improvements, measured in acres and tenths freshwater wetlands, not less than [50] per- units, if any, that are proposed to be affordable of an acre, excluding common open space

ZONINGPRACTICE 8.07 AMERICAN PLANNING ASSOCIATION | page 5 (whether or not it is conveyed pursuant to applicable state statute], together with any ordi- (i) the cluster development advances the pur- Section [110] below). The remainder shall be nances and regulations adopted pursuant poses of this ordinance as stated in Section the net buildable area. thereto and appearing in [cite applicable local [101]; and (c) Convert the net buildable area from acres land development regulations]. (j) [other, such as contiguity requirement for common open space]. to square feet (SF), using the equivalency of 107. Review Criteria 43,560 SF = 1 acre. (1) In reviewing a residential cluster develop- (2) The [local planning commission] may, in its (d) Divide the net buildable area by the small- ment, the [local planning commission shall opinion, apply such special conditions or stipula- est minimum lot size (in square feet) per unit determine whether: tions to its approval of a residential cluster devel- for a dwelling unit permitted in the zoning opment as may be required to maintain harmony (a) the site plan satisfies the requirements of district. This figure shall be rounded to the with neighboring uses and to promote the objec- Sections [103], [104], and [105]; nearest lower number to establish the maxi- tives and purposes of the comprehensive plan and mum number of dwelling units to be permit- (b) buildings and structures are adequately the zoning and subdivision ordinances. ted in the cluster development. grouped so at least [25] percent of the total area of the site is set aside as common open space. To (3) If the [local planning commission] finds that The bonus provisions in Section 105 (3) the greatest degree practicable, common open the requirements of paragraph (1) above are sat- space shall be designated as a single block and isfied, it shall approve the residential cluster below are a means by which a local government not divided into unconnected small parcels development, subject to any special conditions can ensure that new housing will benefit low- and located in various parts of the development; or stipulations pursuant to paragraph (2) above, moderate-income households and implement any density bonus pursuant to Section [105], and state goals for affordable housing. Indeed, should any reductions [and/or waivers] pursuant to Section [108]. a local government decide it wants to more aggressively provide for affordable housing Most local governments have adopted through cluster development (as well as open standard design specifications for streets. This space conveyance) it might increase the density allows the planning commission to reduce street bonus from the suggested figure of 25 percent. pavement widths in order to minimize impervi- ous surfaces on the site, as well as to limit the (3) The [local planning commission] may approve an increase of up to [25] percent of the maximum (Above) Terminal vista: “Reverse-frontage” portions of the site that must be regraded to number of dwelling units in the cluster develop- lots should never be allowed to be created at accommodate wider streets. If a street proposed ment, as calculated in paragraph (2) above, if: the end of a cul-de-sac, causing the back end in a cluster development is to be used as a con- Note that only when the common open of houses to face directly onto the cul-de-sac nector from an adjoining development or as a space is both conveyed and is accessible to “circle.” (Below) Neighborhood freeway through street, it is probably not a candidate for the public is a density bonus justified. If the design: The combination of excessively wide a reduction in width. There is no firm rule, how- common open space was simply conveyed to streets and the absence of shade trees is an ever, on when a reduction or waiver should be a private entity (as opposed to the local gov- unattractive combination, despite some engi- allowed, and determinations should be made ernment), but there was no public access, a neers’ claims that wider streets are safer and on a case-by-case basis. density bonus could not be approved. that trees constitute “fixed deadly objects.” The 22-foot pavement width shown in (a) the percent of density bonus is no greater brackets assumes a 15-foot travel lane and a than the percent of dwelling units in the cluster seven-foot parking area. If parking were development that are affordable units; and/or desired on both sides of the street, a 28-foot (b) the percent of density bonus is no greater pavement would accommodate two seven-foot than the percent of the gross area of the clus- parking lanes and a 14-foot wide travel lane. ter development that is both: 1. set aside as and conveyed as common 108. Reduction [and/or Waiver] of Certain open space pursuant to Section [110]; Physical Design Requirements and (c) pedestrians can easily access common (1) In approving a residential cluster develop- open space; 2. accessible to the public. ment, the [local planning commission] may (d) the site plan establishes, where applica- reduce the pavement width of any public or pri- While these review criteria are intended to ble, an upland buffer of vegetation of at least vate streets that would otherwise be required by guide the planning commission in the evalua- [50] feet in depth adjacent to wetlands and the [subdivision regulations or other design surface waters, including creeks, streams, specifications for roads] to [22] feet. tion of the proposed cluster development, they springs, lakes, and ponds; cannot replace a sensitive and creative site (e) individual lots, buildings, structures, (2) An applicant who wants the reduction of planner who has the responsibility of designing streets, and parking areas are situated to pavement width of public or private streets as minimize the alteration of natural features, provided for in paragraph (1) above, shall submit cluster development or an experienced profes- natural vegetation, and topography; a statement of justification for the reduction sional planner whose responsibility it is to (f) existing scenic views or vistas are permit- [and/or waiver] along with the final site plan. review the proposal and advise the planning ted to remain unobstructed, especially from commission on necessary design changes. public streets; If the density bonus is to be given on the (g) the site plan accommodates and pre- basis of a guarantee of the provision of afford- 106. Procedures for Review serves any features of historic, cultural, or able housing, there must be a mechanism to archaeological value; (1) The [local planning commission] shall review ensure that the housing, whether it is for sale and approve a residential cluster development (h) floodplains, wetlands, and areas with and any amendments thereto as a land develop- slopes in excess of [25] percent are protected or for rent, will remain affordable for a reason- ment project in the manner provided for in [cite from development; able period of time. This is done through a

ZONINGPRACTICE 8.07 AMERICAN PLANNING ASSOCIATION | page 6 REFERENCES deed restriction and mortgage lien approved modes, and making the development review by the local government’s law director. process more predictable). In addition, because

109. Controls on Resale and Re-rental of smart growth ordinances provide more trans- Affordable Housing Units Used as Basis for portation options and more compact, mixed use Arendt, Randall G. 1996. Conservation Density Bonus development, they inevitably have public health Design for Subdivisions: A Practical (1) Affordable dwelling units used as the basis implications; they encourage walking, bicycling, for approving a density bonus in Section [105] Guide to Creating Open Space and human interaction, with the potential to shall be subject to a deed restriction and a mort- Networks. Washington, D.C.: Island gage lien to ensure that newly constructed low- support more active, socially engaged lifestyles Press. and moderate-income sales and rental units that result in better physical and mental health. remain affordable to low- and moderate-income Arendt, Randall G. et al. 1994. Rural by households for a period of not less than [30] Design. Chicago: APA Planners years, which period may be renewed. The following should have been included Press. (2) The deed restriction and mortgage lien shall in About the Authors in last month’s issue. be approved by the [local government] law direc- Diehl, Janet, et al. 1988. The Zoning Practice regrets the accidental tor and shall be enforceable by the [local govern- error: Conservation Easement Handbook: ment] through legal and equitable remedies. Managing Land Conservation and “This article is distilled by the authors from 110. Conveyance of Open Space Historic Preservation Easement material in a forthcoming PAS Report, (1) Common open space provided by a residential Programs. Washington, D.C.: Trust cluster development shall be conveyed as follows: Zoning as a Barrier to Multifamily Housing for Public Land and Land Trust (a) To the [local government] and accepted by Develop ment , co-authored by Gerrit Knaap, Alliance. it for , open space, agricultural, or other Stuart Meck, Terry Moore, and Robert Ewing, Reid. 1996. Best Development specified use or uses, provided that the con- Parker, released by APA in July 2007. veyance is approved by the [local planning Copyright APA 2007. Research for the report Practices. Chicago: APA Planners commission] and is in a form approved by the Press, 69–72. [local government] law director; or was supported by the Lincoln Institute of Land Policy, the Fannie Mae Foundation, Jeer, Sanjay, et al. 1997. Nonpoint Source (b) To a nonprofit organization whose principal purpose is the conservation of open space, to a and the U.S. Department of Housing and Pollution: A Handbook for Local corporation or trust owned or to be owned by Urban Development.” Governments. Planning Advisory the owners of lots or dwelling units within the Service Report No. 476. Chicago: residential cluster development, or to owners of American Planning Association, shares within a cooperative development. If such a corporation or trust is used, ownership Single-family homes clustered around 81–90. shall pass with the conveyances of the lots or a common green. ©iStockphoto.com/ Livable Oregon, Inc. n.d. Skinny Streets: dwelling units. The conveyance shall be Joe Gough approved by the [local planning commission] Better Streets for Livable Communi- and shall be in a form approved by the [local ties. Portland, Ore: Livable Oregon. government’s] law director . VOL. 24, NO. 8 Sanders, Welford G. 1980. The Cluster (2) In any case, where the common open space Zoning Practice is a monthly publication of the in a residential cluster development is conveyed Subdivision: A Cost-Effective American Planning Association. Subscriptions pursuant to subparagraph (1)(b) above, a deed Approach. Planning Advisory Service restriction enforceable by the [local government] are available for $75 (U.S.) and $100 (foreign). W. Report No. 356. Chicago: American shall be recorded that provides that the common Paul Farmer, FAICP, Executive Director; William R. Planning Association. open space shall: Klein, AICP, Director of Research. (a) be kept in the authorized conditions(s); Southworth, Michael, and Eran Ben- Zoning Practice (ISSN 1548–0135) is produced at and Joseph. 1997. Streets and the APA. Jim Schwab, AICP, Editor; Michael Davidson, (b) not be developed for principal uses, Guest Editor; Julie Von Bergen, Assistant Editor; Shaping of Towns and Cities. New accessory uses (e.g., parking), or roadways. York: McGraw-Hill. Lisa Barton, Design and Production. Stein, Clarence S. 1957. Toward New CONCLUSION Copyright ©2007 by American Planning Towns for America. New York: This overview of the structure of cluster develop- Association, 122 S. Michigan Ave., Suite 1600, Reinhold Publishing Co, 37-34. ment is part of larger effort by the American Chicago, IL 60603. The American Planning Planning Association to develop model smart Association also has offices at 1776 Unterman, Richard, and Robert Small. Massachusetts Ave., N.W., Washington, D.C. growth ordinances, including models that may 1977. Site Planning for Cluster 20036; www.planning.org. Housing. New York: Van Nostrand be adapted by local governments to implement All rights reserved. No part of this publication may Reinhold. special planning policies (e.g., multimodal transportation, affordable housing, etc.). As be reproduced or utilized in any form or by any Whyte, William H. 1964. Cluster used in this effort, smart growth ordinances and means, electronic or mechanical, including photo- Development. New York: American development codes mean regulations intended copying, recording, or by any information storage Conservation Association. and retrieval system, without permission in writing to achieve a variety of objectives (e.g., encourag- from the American Planning Association. ing mixed uses, preserving open space and environmentally sensitive areas, providing a Printed on recycled paper, including 50-70% choice of housing types and transportation recycled fiber and 10% postconsumer waste.

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