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Standards in Sustainable

Cayce Bean and Chia-Hui Yang (Mayla)

csd Center for

UTSoA - Seminar in

Standards in Sustainable

Cayce Bean Chia-Hui Yang (Mayla)

Fig. 01 Kresge Foundation Headquarters, Troy, Michigan

Sustainable Landscape goals of these eight parameters Architecture address environmental benefits. and conservation Sustainable landscape architecture both strive to work creates ecological for the with to reduce air , outdoor and urban environment. It increase water quality, lower beginss with appropriate systems water , utilize native which address function, cost, , and reduce usage of pest energy efficiency, beauty, the and control. However, sustainability and environment. Broadly speaking, conservation differ in the emphasis sustainable landscape architecture is sustainability places on addressing the integration of ecological, social, social and economic factors in cultural, and economic factors in addition to environmental factors. In designing to help protect other words, conservation can be habitat, contribute to seen as the environmental part of the management, conserve water, sustainability concept. among other objectives. The current trend in the practice of landscape Scope architecture is to find the balance of “ and function” required for The first part of this paper examines successful sustainable .1 the Sustainable Sites Initiative as an example of a current benchmark Sustainability vs. Conservation and rating system for landscape architecture. The second part of The Chesapeake Conservation this paper addresses the concept Landscaping Council (CCLC) of living systems and details two defines “Eight Essential Elements” materials, water and vegetation, for conservation landscaping.2 The which are relevant to

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Initiative won a 2009 Green Business Award.

Overview

The initiative’s definition of sustainability derives from the well-known Brundtland report. To be sustainable, a site has “design, , operations, and maintenance practices that meet the needs of the present without compromising the ability of future generations to meet their own needs.”6 Sustainable sites do not only mitigate negative impacts on the environment, but are a mutual benefit to the site itself and the people who use it. In addition, a sustainable site must address

Fig. 02 Aspects of Sustainability social, environmental, and economic concerns. The economic aspects addressed must take into account both the Sustainable Sites Initiative building guidelines and rating the value of the natural systems and to living systems. This section systems. To this end, the USGBC of the site. This is the root of the also concludes with a few examples anticipates eventual adoption in program’s ecosystems services of living systems strategies. to their Leadership in Energy and framework. In other words, the (LEED) guidelines have been built around Sustainable Sites Initiative program. The Sustainable Sites the concept that people receive guidelines, however, will not apply benefits, in the form of goods and History and Objectives only to sites with buildings, rather, services from healthy ecosystems. “the Initiative seeks to apply The Sustainable Sites Initiative sustainability principles to any site, Ecosystem services grew out of a conference hosted with or without buildings, which in 2005 by the American Society will be protected, developed or Ecosystems provide goods and of Landscape (ASLA), redeveloped for public or private services to us that without which 4 the Lady Bird Johnson Wildflower development.” The Initiative sees we would not be able to survive. Center. The Botanical the opportunity for the guidelines Often, when evaluating the economic (USBG) joined the effort in to be applied to a wide range of considerations of a development 2006 when the initiative officially projects from to college project, these services are began. The United States Green campuses to utility corridors. To inadequately valued or neglected Building Council (USGBC) became a achieve this broad application, the entirely. This can result in an 3 stakeholder in 2007. stakeholders are also interested in inaccurate analysis that hides many partnering with local organizations of the potential costs and benefits 5 The main goals of the initiative over common objectives. The draft to the project and to the site. In are to create a set of guidelines report of Performance Benchmarks addition to these more tangible and benchmark which become was released in 2008 and the factors, ecosystems can contribute a stand alone guide and rating Performance Benchmarks were to “our healthy, our prosperity, our system for site sustainability and released November 5, 2009. In security, and to our social and to serve as a supplement for other October 2009, the Sustainable Sites

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MOUNTAIN FOREST & DRYLANDS CULTIVATED URBAN ISLANDS AND POLAR • Global climate • Pollination • Global climate • Air and water • Local climate • Global climate regulation • Food and regulation cleansing regulation regulation • Erosion and renewable • Local climate • Water supply and • Water supply • Local climate sediment control non-food regulation regulation and regulation regulation • Pollination products • Air and water • Hazard mitigation • Erosion and • Air and water • Waste decomposition cleansing • Human health sediment control cleansing and treatment • Human health and and well-being • Human health and • Erosion and • Food and renewable well-being benefits benefits well-being benefits sediment control non-food products • Cultural benefits • Food and renewable •Food and renewable • Habitat functions non-food products non-food products • Waste decomposition • Cultural benefits and treatment • Human health and well-being benefits • Food and renewable non-food products • Cultural benefits

INLAND WATER COASTAL MARINE • Water supply and regulation • Water supply and regulation • Global climate regulation • Hazard mitigation • Hazard mitigation • Waste decomposition • Waste decomposition and treatment • Habitat functions and treatment • Human health and well-being benefits • Waste decomposition and treatment • Food and renewable • Food and renewable non-food products • Human health and well-being benefits non-food products • Food and renewable non-food products • Cultural benefits • Cultural benefits

Fig. 02 Examples of some of the goods and services various ecosystems can provide for communities. cultural identity.”7 10. Food and renewable non-food strategies is a cost worthy expense. products This means “presenting an The initiative has defined twelve 11. benefits9 accurate valuation of the benefits of essential ecosystem services. A ecosystems.”10 sustainable site should protect Often, sites are not developed in a and enhance these services.8 The way to preserve these services or Ecosystem services are the structure specified ecosystem services are: they are used and then abandoned for the Initiative’s guidelines because as brownfields. Even brownfields, they believe that any landscape 1. Global climate regulation however, are performing some “holds the potential both to improve 2. Local climate regulation valuable ecosystem services and and to regenerate the natural 3. Air and water cleansing furthermore, could be restored in benefits and services provided by 4. Water supply and regulation such a way to restore and enhance ecosystems in their undeveloped 5. Erosion and sediment control the ecosystem services of the site. state,” and that sites can be 6. Hazard mitigation In the restoration of brownfields, in developed in a way to enhance these 7. Pollination particular, and the development of services and improve the benefits for 8. Habitat functions new projects, in general, there is a the humans and the ecosystem.11 9. Waste decomposition and challenge to convince developers treatment that changing conventional site

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Guidelines and Benchmarks

The goal of the initiative produced performance benchmarks is to “develop credits that would shift the landscape development and management market toward sustainability while still being practical and achievable.”12 This focus on achievable outcomes, however, is not an allowance for less rigorous solutions – the bar has been set high. The stakeholders have acknowledged that defining the credits and how they are quantified and measured will need to be an evolving process, adapting to new conditions, technologies, and trends, in addition to responding to the performance of previously attempted solutions.

The benchmarks are performance Fig. 04 Landscape Architecture intergrate the Living Material to build the Living Systems based and interrelated for several reasons. Ecosystem conditions cannot be generalized between 1. Site Selection the concept of landscape materiality, region. A strategy that works 2. Pre-design Assessment and rejecting nature as naturally positively in one region may be occurring and instead embracing neutral or detrimental in another 3. Site Design – Ecological it as a dynamic set of constructed region. The credits are designed Components systems. In living systems, to encourage a holistic approach to 4. Site Design – Human Health landscape architecture integrates site development because it is the Components living materials such as plants and view of the stakeholders that no one 5. Site Design – Materials Selection water working within the complex successfully addressed credit, or 6. Construction behaviors of biological systems. issue, can make a site sustainable.13 7. Operations and Maintenance Landscapes are also viewed as However, prerequisite credits must a series of cyclical and evolving be met to qualify as a sustainable Each benchmark addresses a processes in which materiality is site. There is a process for specific set of ecosystem services defined in terms of capabilities, amending the prerequisites since the as related to one of five expertise growth, decay, exchange, stakeholders acknowledge that not areas: soils, vegetation, , conversion, adaptation, retention, all apply to every site. Credits that materials selection, and human infiltration, and evaporation. As a are benchmarks that are optional. health and well being.15 These topics system of continual flux, exchange, are identified as the key technical and transformation, landscapes The credits are categorized and areas that must be addressed by must be integrated into their design structured in such a way as to guide sustainable sites. propose and material structure, not the project team through the process just an applied surface layer.16 from site selection to operations and Living Systems Living systems incorporate many maintenance.14 The seven major of the technical areas of the framework categories are: The idea of living systems broadens Sustainable Sites Initiative including:

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urban , new adaptable sites, stormwater management, and climate control, vegetation, and hydrology among others.17

Living Materials -Water Precipitation Condensation Water covers 70% of the Earth and essential to life in general and sustainability and landscapes Evaporation in particular. With respect to sustainable landscapes it is Surface runo Surface runo important to understand water as a system rather than a substance. Transpiration When analyzed as a system, less emphasis is placed on controlling location and more emphasis is Evaporation placed on the effects of surface interventions on the movement of uptake 18 Inltration into water locally and regionally. It groundwater is also important for to Groundwater ow have a basic understanding of the Aquifer hydrological cycle. Fig. 05 The Hydrological Cycle The hydrological cycle, also known as the water cycle, describes the and greater erosion. Conversely, pollutants can contaminate drinking way that water moves through our sensitively addressing these factors and groundwater. ecosystems. As it is a never-ending can enhance a site dramatically in cycle it is important to protect water addition to improving conditions on This excess volume, when not at every step of the process.19 neighboring sites and enhancing the managed on site, is called runoff. In local watershed. other words, runoff is “rainwater that There are three major factors can’t be collected where it falls.”21 which influence the way that water In the scope of this section the Like stormwater, runoff can be a performs on a specific site: the following topics will be addressed: major source for some bodies of quantity of water, the material over storm water, water collection, and water, but excess runoff can also which the water runs, and shape of constructed wetlands. cause flooding downstream. It the land over which the water runs. can also lead to erosion due to an A moderate amount of water flowing Stormwater unexpected amount of water flowing over a gentle slope with porous over a steeper slope or softer soil. soil will likely be absorbed by the Stormwater is water that hits the soil. The same amount of water earth as precipitation. While Runoff is also a major source of on a steeper slope with impervious stormwater through infiltration is pollution; for example, contaminates, material will run-off to a different they way in which our ground water, including bacteria, on pavements are location.20 Due to these factors, it is streams, and lakes are recharged, easily washed away and taken into easy to see how construction greatly there are two major issues regarding the hydrological cycle.22 Pavements effects water performance. Soils the problem of excess stormwater: and other impervious surfaces are can be compacted or replaced with volume and pollution. Excess also a major contributing factor paving materials and slopes can volume generally leads to flooding to an increase in runoff because be regraded leading to more runoff while surface and atmospheric these surfaces greatly decrease

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end of a gutter to a “multiple end- use system at a large corporate campus.”26 The key difference is that with water harvesting, water is seen as a resources, as opposed to the conventional water management view of excess water as something to be controlled and mitigated.27

Almost any surface can be used to collect water, but a few guidelines should be followed. Firstly, the water collected from paved surfaces cannot be used as drinking water, but can serve for plant watering and countless other water needs. If the surface is a low pollutant surface, such as paved surfaces with no Fig. 06 Comparative surface runoff and pollutants vehicular traffic, then it can feed directly into a collector. If the surface is a pollutant surface, then before the absorption of a given area of downstream to the next landowner. being collected it must go through a land. Due to these increases in The second reason is that larger biofilter or bioswale. pollution and potential flooding, scale techniques are perceived as reduced infiltration capacity is “one having economies of scale. In this The simplest water collection of the single most serious barriers to view, costs related to performance method, of course, is to the sustainability.”23 and maintenance are largely site toward a planted bed or wetland ignored; this is a faulty view however, area. There are, however, a few Stormwater management is most because capital costs fail to reveal precautions for this system. Care efficient and cost effective if a complete picture. Reinforcing this must be taken with every plant; controlled where the precipitation point, according to one study, “at the site increases the hits the earth. The reasons for this least in the Eastern United States, chances that specific plants will are simple. As runoff moves over every gallon of water properly be either drowned or parched by greater distances its speed increases managed on-site saves at least $2 in this movement of water. Secondly, and it accumulates more volume in a downstream.”24 although can be used snowball effect. Volume and speed, strategically for many sustainable while problematic on their own, are Water Collection design strategies, they also can also primary factors in the erosive loose a significant amount of volume of water. Historically, many have due to evaporation.28 taken advantage of water collection There are two main explanations systems. Additionally, as recently In addition to ponds, water can also of why, despite these factors, as the turn of the 20th century be stored in containers either above often storm water is not managed many often had water or below ground. These tanks are closed to its source. The first is harvesting systems and cisterns. generally made of metal, plastic, that upstream landowners may Water harvesting is defined as “the fiberglass, or concrete, but can also choose not to or do not adequately collection and storage of rainwater be made of stone or wood. Above manage their runoff. In this case, from roofs, paved surfaces, and ground, the tanks should be opaque the downstream landowner has the landscape.”25 Systems for because sunlight will increase the little choice and must manage the water collection vary in size and growth of algae. Below ground storm water or continue to send it scope from a single barrel at the

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tanks, although more expensive to install, have the added benefit of a more moderated temperature throughout the year. The use to which the water will be put should be considered when selecting the material because some can be toxic for drinking water.

Constructed Wetlands

Natural wetlands are sometimes called “earth’s kidneys” because they serve to filter out contaminants in the water of our ecosystems.29 Wetlands slow the flow of water, allowing sediments to fall out. In addition, Fig. 07 Subsurface flow wetland wetlands host a variety of plants and microorganisms that can serve to improve water quality. Constructed wetlands, in recent years, have begun to be promoted by many organizations, including the United States Environmental Protection Agency, as an alternative method to .30 Some go so far as to say that “it is quite conceivable that within a few years it will be landscape professionals who deal with waste water treatment, not sanitary engineers.”31 Constructed wetlands have the potential benefits of having lower construction maintenance costs, being more Fig. 08 Surface flow wetland aesthetically pleasing, and producing less odor than traditional treatment flows over a vegetation supporting wetlands without a flow of water facilities. substrate where to roots and directly on the surface, are used microorganisms filter pollutants.33 primarily near housing or office The technology for constructed Generally the ponds are 1 – 3 feet buildings because there is less wetlands is not new; it originated in deep and have an impervious liner. of human contact, less risk Germany in the 1960s and came to The bottom is filled with gravel, of mosquitoes, and less odor. the United States in the 1980s. In or some other porous material However, because they are covered, fact, despite meager adoption in capable of supporting plant life. The they are less reliable and harder to this country, over 5,000 constructed arrangement of the upper layers maintain if needed. With subsurface wetlands for the purpose of water depends on the type of wetland, flow wetlands, the gravel in the treatment have been implemented either subsurface flow or surface ponds is topped with mulch and 32 in . At its most basic, a flow. plants. When operating, the water is a shallow flows under the mulch directly on top which is split into cells. Water Subsurface flow wetlands, that is of the gravel.

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In contrast, surface flow wetlands, have no or a very shallow mulch layer. Plants are grown in the gravel layer and when operating water flows directly on the surface. This system is less complex and therefore costs less to install and operate. It is also more efficient and it supports a more diverse wildlife habitat. The appropriate strategy is specific to each situation and should be evaluated on a site by site basis.34

Living Materials - Vegetation

Xeriscaping

Xeriscape taken from xeros, meaning dry in Greek is a word firstly coined by the Denver Water Development in 1981 to set up an exemplary model of water saving landscapes.35 In the western United States, more than 50% of residential water demand is used to keep landscapes and lawns green. can reduce the water usage by 15% to 60%. Its Fig. 09 Vertical Landscapes show the integration of Architecuture and Landscape basis is seven essential principles to reestablish : environments. providing a vehicle for connecting 1. planning and designing, urban residents to the natural world, 38 2. limiting turf areas, Landscaping with Native Plants and promoting a conservation ethic. 3. selecting and plants appropriately, Native plants are plants that have Living Strategies 4. improving the soil, evolved naturally in particular area 5. using mulch, before the human introduction Vertical Landscapes 6. irrigating efficiently and of foreign species. They can 7. maintaining the landscape36 be incorporated into traditional Vertical landscapes are a strategy landscape or used more which show the potential for Xeriscape is often associated with creatively in less conventional structural and formal continuity cactus and rock gardens, but these landscaping. Using native plants between landscape and architecture. landscapes can incorporate a wide in results in a Based on the tendency of plants variety of seasonally diverse species. substantial savings of water and to adapt growth to a structure and The underlying tenets of Xeriscaping lower maintenance costs when towards the direction of nutrient promote regionally and climatically compared with conventional sources, vertical landscapes are able 37 appropriate landscaping with native landscape designs. Native to redefine the idea of landscape plants, but also can and should be landscaping strengthens local as existing solely in the horizontal used to promote more sustainable cultural identity by re-introducing plane. These systems consists of a the natural heritage of an area, a non-living structure which supports

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ground water recharging.41

Maintenance Systems

Maintenance within landscape architecture is generally viewed as the preservation of a state. When viewed through the lens of living systems, maintenance instead is articulated as a responsive pattern of cultivation that enhances a more phenomenological reading of the landscape. Maintenance can be well- organized performance throughout the lifecycle of a landscape site.42

Metabolic Systems

One way to view brownfields is as metabolic systems; in this view all materials and processes are inputs and outputs within a larger “food cycle.” This means that hrough site metabolism, material resources are generated, retained, balanced, and reconfigured into new resources. In response to

Fig. 10 Stratified Landscape redefines the ground as a three-dimensional profile the idea of metabolic systems, remediation proposals have begun to shift from off site pollutant removal vegetation. The vegetation, in can be on the top of a capped to in-situ strategies. Additionally, turn, provides a skin that can help or a roof structure, or floating within a new bio-based processes and 40 to control light, air quality, and watercourse. technologies to increase physical temperature. The structure could and economic performance of be transitional, biodegradable, Fluid disused sites are increasing and permanent, or designed to evolve offer new opportunities to incorporate symbiotically, so as to adapt itself to Fluid landscapes are designed to these processes into the spatial, 39 different stages of growth. flexibly accommodate the cyclical aesthetic, and experiential layout of and seasonal fluctuations of water landscapes.43 3-Dimensional Profile flow and to flexibly manage water volume, frequency, and velocity. Conclusion A stratified landscape strategy Since, the majority of surfaces in the redefines the ground plane from are impervious, Sustainable landscape architecture a traditional material classification these methods of small- scale, local takes into account enconomic, to an armature of 3-dimensional water retention, and infiltration begin social, and environmental aspects profiles housing dynamic living to compensate for the depletion of of landscapes. There are many systems. They are arranged with a the nature sponge structures such different approaches to landscape top interface layer down to a series as soil and wetlands, that were once sustainability, but all would agree of overlapping horizons within each widely dispersed to attenuate the on a few key aspects. First, there site (Figure 10). These landscapes volume of surges, as well as facilitate

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is no right solution that will produce 16. Liat Margolis, Living Systems: Innovative a sustainable landscape everytime. Materials and Technologies for Landscape 36. Ibid. Architecture (a Basel: Birkhäuser, 2007), Secondly, every proposal must be 10-11. 37. “Why Native Plants.” Lady Bird Johnson contextually responsive and specific. Wildflower Center. http://www.wildflower.org/ Finally, sustainable landscapes are 17. Ibid. whynatives/. not just about creating green spaces, 18. J. William Thompson, Sustainable 38. Margolis, Living Systems, 10-11. but are about implementing design Landscape Construction: A Guide to Green that can benefit both humans and Building Outdoors (Washington, D.C: Island 39. Ibid., 14-15. ecosystems simultaneously. Press, 2000), 133. 40. Ibid., 36-37. 19. U.S. EPA, “Water Availability,” Environmental Protection Agency, http:// 41. Ibid., 56-57. ... www.epa.gov/climatechange/effects/water/ availability.html. 42. Ibid., 76-77.

20. Thompson, Sustainable Landscape 43. Ibid., 100-101. Notes Construction, 134. ...

1. “Sustainable Landscape Architecture 21. Thompson, Sustainable Landscape 101.” The Dirt. http://dirt.asla.org/2009/06/03/ Construction, 136. sustainable-landscape-architecture-101/. Figures 22. U.S. EPA, “Stormwater Management,” 2. “Chesapeake Conservation Landscaping Environmental Protection Agency, http://www. Page: “Point Fraser Precinct Council Home.” Chesapeake Conservation epa.gov/greeningepa/stormwater/index.htm. Landscaping Council. http://www. Development.” Sustainable Sites Initiative. chesapeakelandscape.org/. http://www.sustainablesites.org/cases/enlarge. 23. Thompson, Sustainable Landscape php?id=6&image=1. Construction, 136. 3. “About Us.” Sustainable Sites Initiative. http://www.sustainablesites.org/about/. Figure 01: “Kresge Foundation 24. Ibid. Headquarters.” Sustainable Sites Initiative. http://www.sustainablesites.org/cases/enlarge. 4. “FAQs,” Sustainable Sites Initiative, http:// 25. Ibid., 154. www.sustainablesites.org/faqs/. php?id=14&image=1. 26. “The Manual on Rainwater 5. “Guidelines and Performance Benchmarks Figure 02: “Guidelines and Performance Harvesting, Third Edition” (Texas Water Benchmarks - Draft 2008.” The Sustainable - Draft 2008.” The Sustainable Sites Initiative, Development Board, 2005), 3. 2008, 4. Sites Initiative, 2008, 8. 27. Thompson, Sustainable Landscape 6. Ibid., 6. Figure 03: “Guidelines and Performance Construction, 158. Benchmarks - Draft 2008.” The Sustainable Sites Initiative, 2008, 11. 7. Ibid, 10. 28. Ibid., 158. 8. Ibid, 12. Figure 04: Liat Margolis, Living Systems: 29. “Constructed Treatment Wetlands” (United Innovative Materials and Technologies for States Environmental Protection Agency, 9. Ibid. Landscape Architecture (a Basel: Birkhäuser, August 2004), 1, http://www.epa.gov/owow/ 2007), 95. wetlands/pdf/constructedw_pr.pdf. 10. Ibid., 19. Figure 05: “Guidelines and Performance 30. Thompson, Sustainable Landscape Benchmarks - Draft 2008.” The Sustainable 11. “Why Sustainable Sites?,” Sustainable Construction, 166. Sites Initiative, http://www.sustainablesites. Sites Initiative, 2008, 13. org/why/. 31. Ibid. Figure 06: J. William Thompson, Sustainable Landscape Construction: A Guide to Green 12. “Guidelines and Performance Benchmarks 32. “Constructed Treatment Wetlands,” 1. - Draft 2008,” 31. Building Outdoors (Washington, D.C: Island Press, 2000), 166. 33. Thompson, Sustainable Landscape 13. Ibid. Construction, 166. Figure 07: 1. “Constructed Wetlands,” Natural 14. Ibid., 32. Systems International, http://www.natsys-inc. 34. Ibid. com/resources/about-constructed-wetlands/. 15. Ibid, 31. 35. “Xeriscape.” Denver Water. http://www. Figure 08: “Constructed Wetlands,” Natural denverwater.org/Conservation/Xeriscape/. Systems International, http://www.natsys-inc.

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com/resources/about-constructed-wetlands/.

Figure 09: Liat Margolis, Living Systems: Innovative Materials and Technologies for Landscape Architecture (a Basel: Birkhäuser, 2007), 33.

Figure 10: Liat Margolis, Living Systems: Innovative Materials and Technologies for Landscape Architecture (a Basel: Birkhäuser, 2007), 39.

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