A. Ecological Planning / Sustainable Design

    It seems appropriate to conclude by looking at the environmental implications of site planning.  There is a burgeoning awareness of the critical need to change the American attitude toward land.  Until recently we seemed to treat land as a disposable commodity, to be used and then discarded, moving on to a new site.  This attitude is manifested by the “urban sprawl” that is prevalent in increasing patterns around our major cities.  This phenomenon which has been widely reported on in recent years has resulted in, as Vincent Scully describes it, “that vast area in which most Americans now live, sprawled between the metropolitan center, which is emptying out, and the open countryside, which is rapidly being devoured” (qtd. in Katz 221).

    Essentially, as America became more mobile as a result of the automobile, people began to move out of the city to the suburbs.  This not only was the cause of urban decline, but it has placed an increasing demand on the conversion of rural agricultural lands to housing and other more intensive development.  As our highway system expanded, people were able to commute greater and greater distances from their homes to their jobs in the city.  This in turn soon led to the demand for more convenient retail, service, and recreational facilities closer to home.  Eventually these decentralized clusters of commercial and office buildings outgrew the old cities that they surrounded.  This phenomenon has resulted in what Joel Garreau has coined as “Edge Cities.”  We now find that people are moving outward even farther from these nodes, creating yet another layer of sprawl.  Peter Calthorpe discusses this situation, pointing out the irony that today, “the suburb-to-suburb commute represents 40% of total commute trips while suburb-to-city comprises 20%” (Katz xii).

    In terms of public attitudes, we now seem to be realizing the folly of this spiraling uncontrolled growth.  Once land is developed it is gone.  As Mark Twain once said, “God’s not making any new land these days”  (qtd. in Castillon 359).  There are several anti-sprawl or “smart growth” movements currently gaining headway.  In a recent Time Magazine article, there was a discussion of the political mobilization of smart growth on the local, state, and national levels.  Vice President Gore is even being touted as the anti-sprawl candidate of 2000 (Lacayo 45).

    People are beginning to see that sprawl is not simply a result of population growth, but equally the end product of a series of compounding factors.  For example, local land use controls actually encourage new development on the fringes by making it easier and less expensive to build beyond existing development.  Since local governments must generate funds to provide required infrastructure they are often in competition with one another for tax revenues.  This creates an environment in which they are inclined to give preferential treatment to higher tax-producing land uses such as retail centers rather than residential uses.  Large lot, low-density residential zones also discourage new development within the urban areas where land values are higher.  The outlying lands – agricultural lands, woodlands, open space – are often the least resistant to development, physically and legally.  Lastly, federal funds, through highway expansion programs, actually facilitate the movement outward from the city, making it easier for people to commute greater and greater distances.

    The solution to this growing problem lies in an overall comprehensive approach such as we discussed earlier.  Some communities have developed growth management programs that literally establish a ring around the city.  New, compact, mixed land use development is channeled into designated “Growth Areas” within the ring.  Outside of these “Growth Boundaries” growth is severely restricted, keeping sprawl out of open lands, preserving them for agriculture, woodlands, and recreation.

    Such a program must be supported by stronger regulations.  Local ordinances must be adapted to provide for higher density mixed land use growth within the urban boundaries.  Policies also need to be established that encourage urban in-fill.  There are several approaches to revitalization that provide financial incentives to homeowners and businesses to locate within the city through historic restoration or adaptive re-use of existing buildings or sites.  At the same time local and state planning regulations and policies can support growth management strategies by delineating environmental and conservation priorities.  A commitment to conserve open space and critical habitats, supported by programs providing tax incentives, facilitates the decision of land owners to protect ecologically sensitive lands and encourages the developer to consider other options.  From a regional perspective, alternatives to new highways, ranging from improvement of local roads to the development of mass transit systems, can significantly deter the impetus of sprawl.

    While from an individual standpoint the current growth pattern may seem economically beneficial, the cumulative costs are not.  Growth management techniques such as Urban Growth Boundaries work by treating  “the city, its suburbs and their natural environment . . . as a whole – socially, economically, and ecologically . . .” (Katz xi).  This is all part of a more proactive approach to planning for land development to simultaneously contribute to our quality of life while maintaining a sense of ecological integrity.

    The concepts of ecological design and sustainable design, which support this newer approach, are used interchangeably.  “Sustainability allows us to provide for present needs, while promoting long-term ecological and physiological health and productivity”  (Motloch 267).  Ecology is the study of the relationship of all living things to their biological and physical environments.  Sustainable design is then “the intentional planning and design of human ecosystems through the application of ecological understanding, to make conscious informed decisions concerning conflicts between human and ecosystem needs”  (Motloch 272).

    Steiner proposes an ecological planning model that attempts to use “biophysical and sociocultural information to suggest opportunities and constraints for decision making about the use of the landscape”  (Steiner 9-10).   This model involves eleven interconnected steps, including:

1. Identification of issue or issues.
2. Establishment of a goal to address the issue(s).
3-4. Inventories and analyses of biophysical and sociocultural
systems from the larger down to the specific level.
5.  Detailed studies to link inventory and analysis to problem(s) and goal(s).
6. Development of concepts and options.
7. Preparation of a landscape plan.
8. Presentation to and response from affected public.
9. Development of detailed designs for individual sites.
10. Implementation of detailed designs.
11. Administration of plan.

(See Figure 20)

    The application of McHarg’s approach as he describes it, requires elaborate ecological inventories . . .  When such inventories are completed they can be constituted into a value system.  They can be identified not only in degrees of value but of tolerance and intolerance . . . Ecosystems can be viewed as fit for certain prospective land uses in a hierarchy.  It is then possible to identify environments as fit for ecosystems, organisms and land uses.  The more intrinsically an environment is fit for any of these, the less work of adaptation is necessary.  Such fitting is creative.  It is then a maximum-benefit/minimum-cost solution  (McHarg, 197).

    This inventory and subsequent analysis occurs at the local scale, providing an understanding of natural factors in relationship to potential human activities.  McHarg’s method entails a layering of information that can then be assessed in the context of human ecosystems.

    The third scale level is that of the specific site in which particular problems and goals are linked to the completed inventory and analysis.  This allows the planner to determine the suitability of a given site for one or more proposed land uses on the basis of the completed ecological studies tempered by the human values for those land uses.

    The key aspects that must be stressed are the comprehensive overview and the involvement of the affected public.  These require an understanding and focus upon “human ecology” which is how people interact with each other and with the environment.  As Steiner summarizes the ecological planning model, it “is not . . . a rigid, lockstep approach . . . but rather a flexible, iterative method . . . The method is a framework for problem solving” (317).  The bottom line is that functional, sustainable landscapes must be planned with equal consideration for natural and human concerns.  “Nature is a matrix within which designs find an identity and a coherence that contribute to the health of the whole.  Ecological designs are articulated within an ecosystem or bioregion in the way veins are articulated within a leaf.  They fill out an existing structure in a way that enhances the life, the flows the processes within it” (Van der Ryn 105).

    B. Environmentally Sensitive Design

    This last section will illustrate some applications of the concepts and principles discussed above to site planning and design.  In other words, what are some of the specific sorts of physical planning techniques that may be employed to achieve ecological health and sustainability?
 

1). Planning Level – On the regional level there are some approaches that can be implemented to provide for economic development while protecting the landscape character and minimizing the negative environmental impacts of growth.  The University of Massachusetts Center for Rural Massachusetts identified the Connecticut River corridor as a critical area vulnerable to mounting development pressures.  The planners identified a number of significant issues ranging from soil erosion and stream sedimentation, to loss of natural resources, threats to agricultural lands, and incompatible historic and cultural impacts.  After analyzing these issues, the University of Massachusetts group devised an approach for sensitive growth and development utilizing a series of legal controls and planning and design recommendations.  One of these, Open Space Development Design (OSDD), utilizes optional or mandatory regulations to establish overlay zones.  For example, a “Rural Preservation District” might be established that prohibits subdivision development from consuming more than 50% of any parcel.  If the base density is 1 unit /10 acres, then the maximum lot size is five acres, with the remaining five acres permanently restricted from development.  Using a sliding scale approach, as the area actually allocated for development decreases, the number of lots can increase (e.g., 60% open space would allow twelve 3.3 acre lots instead of ten; 70% open space twenty 1.5 acre lots instead of ten, etc.)  (Arendt 226-230).

    Transfer of Development Rights (TDR) is another flexible method in which areas suitable for development are designated as “receiving zones”, with increased use densities.  At the same time, open farmlands and woodlands (or other protected areas) are designated as “sending zones”, in which the property owner may sell the development rights to build in the receiving zones.  In return, the sending zones are retained in their undeveloped state, without unduly penalizing the property owner.

    Another legal mechanism is the use of conservation easements.  Conservation easements refer to the transfer of partial interest in property, either in the form of a gift or for a price, to a nonprofit or governmental entity.  The conditions of the easement restrict the use of the land, the character of development or management conditions (i.e., to protect historic or scenic values, to retain the natural conditions, etc.)  As a charitable contribution, the reduced price or donation of land provides a tax incentive for property owners to restrict development of environmentally sensitive lands.

    These sorts of techniques provide the legal basis for the planners to address the issues created by increased development pressures.  The University of Massachusetts group, among others, has proposed techniques for careful expansion while maintaining the rural countryside and cultural and historic regional patterns.  Referred to as “Connecticut Valley Design Guidelines”, these include such creative development alternatives as:

a. Clustering residential development along the edge of the existing woodland to minimize the visual impact of growth on the open rural pastureland.
b. Restricting lot sizes, development densities, architectural character, to respect the historic and cultural character of existing communities.
c. Designating visually and environmentally sensitive areas as agricultural districts to restrict new growth from encroaching upon them.
d. Restricting development adjacent to environmentally sensitive areas (river’s edge, wetlands, ridgelines, etc.) by zoning and or building restrictions to protect the resource and retain its scenic amenity.  (Arendt 100-102)

    The benefit of such techniques is to protect the rural landscape from uncontrolled or poorly controlled patterns of development over open fields or wooded hillsides.  The growing acceptance of such approaches is due to the fact that they encourage sensitive development without restricting the overall growth potential of an area or penalizing the landowner from realizing a profit.

2). Site Design Level – There are many specific design recommendations that can be made at the scale of individual site design.  These may relate to specific environmental issues such as energy and/or natural resource conservation or to cultural and aesthetic concerns.  In essence, they are specific design guidelines that may be used to achieve the general goals established by the comprehensive planning and facilitated by the land use controls discussed earlier. They may include such general responses as:

a. Considering solar orientation when siting facilities to maximize the potential benefits of active and/or passive solar energy.  One example of this would be to lay out a housing development with streets running generally east-west to facilitate a north-south orientation of the houses.

b. Selecting and placing vegetation:

1) Utilizing deciduous trees adjacent to facilities to provide for cooling shade in the summer, while allowing for the benefit of solar warming in the winter.
2) Buffering prevailing winter winds with evergreen plant massing.
3) Channeling cool summer breezes into suitable exterior spaces of a development with masses of vegetation.

c. Considering facility placement to minimize energy costs of grading and to minimize erosion potential from disturbed slopes.

d. Minimizing use of impervious surfacing to reduce surface runoff thereby recharging the water table on site and minimizing potential soil erosion.
(c and d relate equally to the cultural and aesthetic as well.  By concentrating development and nestling it into the edges of the woodland, we can minimize the visual intrusion into the rural character of an area subject to expanding development pressures.)

e. Preserving as much of the existing vegetation as possible as a site development is designed.  Using native or naturalized plant materials will provide suitable habitats for native wild life and facilitate the preservation of migration patterns.

f. Utilizing native building materials, e.g., field stone, native timber, etc. as well as local styles will also help to preserve the visual character of a place.

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