The Dell Medical School
district is the first SITES v2
Gold certified project in Texas.

Dell Medical District—University of Texas at Austin | Photo: Esto

WHY SITES?
The Sustainable SITES Initiative
The Sustainable SITES Initiative (SITES) is a rating system that guides, evaluates, and certifies
sustainability and resilience in the design, development, and management of landscapes andother outdoor spaces. Owned and administered by Green Business Certification Inc. (GBCI),SITES supports landscape architects, planners, developers and others in implementing naturebased solutions. This means that SITES projects prioritize biodiversity and mitigate climatechange while conserving resources, improving public health and providing economic benefits.
SITES certification applies globally to a wide variety of project types and sizes and for sites
with or without buildings—ranging from parks to corporate campuses, urban development
projects to universities, and more. By protecting and restoring ecosystem services, SITES
provides essential benefits to the environment, property owners, and local and regional
communities and economies.

About Green Business Certification Inc. (GBCI)GBCI is the world’s leading sustainability and health certification and credentialing body.
Established in 2008, GBCI exclusively administers project certifications and professional
credentials and certificates within the framework of the U.S. Green Building Council’s
Leadership in Energy and Environmental Design (LEED) green building rating system, as wellas the Sustainable SITES Initiative (SITES), the PEER standard for power systems, the WELL
Building Standard, EDGE (Excellence in Design for Greater Efficiencies), TRUE certification forzero waste and Investor Confidence Project (ICP) for energy efficiency retrofits.
Why SITES? | sustainablesites.orgbTA B L E O F C O N T E N T S
CARBON, ENERGY + CLIMATE................................................................................................. 2
WATER........................................................................................................................................... 3
RESILIENCE .................................................................................................................................. 5
BIODIVERSITY.............................................................................................................................. 7
MATERIALS + WASTE................................................................................................................. 8
HUMAN HEALTH + WELL-BEING............................................................................................. 9
COMMUNITY BENEFITS........................................................................................................... 10

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C A R B O N , E N E R G Y + C L I M AT E
SITES guides projects in reducing carbon emissions and regulating climate, creating positive
impacts at multiple scales. Strategies such as protecting and restoring native habitats,restoring soil, and increasing key vegetation cover help to cool cities and communities.
Promoting the use of low-impact materials, electric or manual maintenance strategies, andenergy-efficient equipment helps to reduce carbon emissions and energy consumption. There
are many ways to reduce carbon in our built environment; however, only landscapes have theunique capacity to sequester and store carbon while creating a more livable place.

Energy Conservation in Buildings
In cool temperatures, trees strategically planted around buildings can serve as a windbreakthat insulates buildings against heat loss. In warmer months, tree cover and the use ofgreen walls and green roofs cool buildings through shading and evapotranspiration.
Evapotranspiration alone can reduce peak summer air temperatures by as much as 2 to 9 °F.
Tree canopy with 20% coverage over a house can result in annual cooling savings of 8 to 18%
and annual heating savings of 2 to 8%. By moderating temperature extremes, vegetation
reduces energy consumption in buildings as well as the carbon emissions and costs
associated with indoor climate control.

Reducing Urban Heat Island Effects
Urban areas that experience significantly warmer temperatures than surrounding rural areas
are known as urban heat islands. This phenomenon occurs because cities typically containbuilding, pavement and road materials that absorb and emit heat; structural masses that
obstruct natural wind flow; and heat-emitting sources such as vehicles and air-conditioning
units. Urban heat islands can experience increased air-conditioning costs, more air pollution,and heat- and pollution-related illness and mortality. However, vegetation protects buildings
and pavement from direct solar exposure, reducing urban heat absorption and emittance.
Parks can be up to 2 °F cooler than the surrounding urban area in the day. The cooling effectof urban green space has been directly correlated with vegetation cover and tree shade area.

Global Climate Regulation and Increasing Carbon Storage
With concerted global action on land use over the next decade, nature can be a significant
part of the climate solution, offering up to 37% of the mitigation needed to prevent global
temperatures from rising more than 2 °C through carbon sequestration and other natural
climate solutions.
SITES requires projects to protect critical functioning ecosystems, such as floodplains andwetlands, so they can continue to provide essential services, including preserving biodiversity,
minimizing flood risks, improving water quality, and sequestering and storing carbon. For
example, the estimated total carbon storage of wetlands globally is 225 billion metric tons
(MT), or the equivalent of carbon emissions from roughly 189 million cars every year—which ismore than the number of registered automobiles in the United States as of 2015. Additionally,
grasslands store approximately one-third of the global terrestrial carbon stocks and can also
act as an important soil carbon sink.
Additionally, grasslands sequester most of their carbon underground, while forests store
it mostly in woody biomass and leaves. When wildfires cause trees to go up in flames, thecarbon they formerly stored is burned and released back to the atmosphere. When fire burns
grasslands, however, the carbon fixed underground tends to stay in the roots and soil, making
them more adaptive to climate change.
To further reduce impacts on carbon, SITES promotes the use of peat-free amendments.
Peatlands are the largest natural terrestrial carbon store and store more carbon than all othervegetation types in the world combined. SITES also promotes the use of low-emitting orelectrical equipment, native and appropriate vegetation, and local and low-embodied-carbon
materials, and SITES encourages projects to promote walking, biking and public transit inorder to reduce carbon emissions. Additionally, SITES also rewards projects that quantify theircarbon impact and make improvements accordingly.
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WAT E R
Natural systems are of critical value for their ability to store, clean and distribute water andto serve as a habitat for a variety of species. SITES encourages designs that conserve water,
maximize the use of precipitation, protect water quality, and protect and restore aquatic
resources. The goal is to incorporate strategies and technologies that restore or mimic natural
systems and ultimately value water as a critical resource rather than a waste product.

Conserving Water
According to a 2014 Government Accountability report, 40 out of 50 U.S. state water
managers expected water shortages under average conditions in some portion of their statesover the next decade. Outdoor water use accounts for more than 30% of total householdwater use, on average, but can be as much as 60% of total household water use in arid
regions.
SITES values water as a precious resource and considers various strategies to conserve water
on a project. First, healthy soils and vegetation work hand in hand to elevate a landscape’s
water retention capabilities. Healthy vegetation maintains soil structure, contributes to soilorganic matter and prevents erosion, creating healthier soils better equipped to store waterand nourish plants. SITES also encourages the use of native drought-tolerant plant species
that require little to no irrigation in order to conserve water. Water retained on site provides
habitat for animal life and ecosystem functions. It can also be used for irrigation, thus
conserving potable water resources and reducing associated energy use and costs. Retainedwater may slowly infiltrate down through the soil, eventually recharging and purifying
groundwater resources, where about 33% of public municipal water and 90% of rural drinking
water is sourced.

Expedia Group Headquarters Campus | Photo: Marion Brenner

Promoting Green Infrastructure
What it means to “manage” stormwater has evolved over time. For many years, managing
stormwater meant collecting rainwater that fell on impervious surfaces such as roofs,
roads and parking lots and transporting it to a stream, river or treatment facility. However,
SITES emphasizes the use of green infrastructure (GI) or low-impact development (LID) as
stormwater controls for improving water quality, reducing stormwater volume, and controlling
erosion and sedimentation. The list of benefits that GI or LID can provide also includes:
improved air quality, reduced heat island effect, improved amenity values and increased
property values.
Why SITES? | sustainablesites.org

3Reducing Stormwater Runoff
When stormwater falls onto impervious surfaces such as roads and parking lots, it is unable
to soak into the soil. Instead, it travels over these surfaces, collecting pollutants such as heavy
metals, petroleum products, bacteria and pesticides. Stormwater runoff can flow directly into
bodies of water, or it can be funneled through stormwater drains into traditional stormwater
management systems. In large storm events, these systems can overflow and discharge
wastewater into nearby bodies of water. Combined sewer overflows may contain untreatedwaste, toxic materials and other debris that cause human illness, water pollution, and thedegradation of aquatic ecosystem health and function. By capturing, treating and reusing
water, SITES-certified landscapes naturally minimize the adverse effects of water runoff.
Additionally, public and private utilities save on the costs and energy expenditures associatedwith stormwater collection and treatment. SITES helps projects maximize their water-holding
retention capacities on site by protecting and restoring soils and landscapes, as well as bypromoting the implementation of GI, such as rain gardens, pervious pavement, green roofs
and bioswales.

Improving Water Quality
Aquatic ecosystems are negatively impacted by pollution from sources such as stormwaterrunoff, as well as changes to the landscape and hydrological systems. SITES encourages therestoration of aquatic ecosystems such as riparian buffers, streams and wetlands. Excess
nutrients, such as phosphorus and nitrogen, cause eutrophication in bodies of water. During
eutrophication, an overgrowth of algae can lead to low levels of dissolved oxygen in thewater, aquatic plant and animal deaths, and contamination of drinking water. When theseecosystems are healthy, they naturally filter pollutants by intercepting surface runoff andremoving, retaining, and processing inorganic nutrients and organic wastes.
SITES also promotes the protection and restoration of floodplains, which reduce waterpollution by providing areas for the deposition of excess sediment carried in floodwaters.
Instead of clogging waterways and smothering habitats, deposited sediment replenishes soils
and nourishes vegetation. Healthy soils, in turn, further filter water resources through physical,
chemical and biological processes.

The Campsite at Shield Ranch | Photo: Leonid Furmansky

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RESILIENCESITES-certified projects mitigate floods, droughts, heat waves, wildfires and other hazards
that pose risks to property owners and the health and safety of humans and habitats. Theserisks are exacerbated by climate change and high-impact development. SITES mitigates thesehazards by protecting and restoring landscapes, enhancing biodiversity and promoting theimplementation of GI and ongoing sustainable management strategies.

Flood Mitigation
Warmer atmospheric temperatures cause more evaporation and larger, more frequent
heavy precipitation events, leading to an increased risk of flooding. Between 1998 and 2014,
the United States spent an estimated $48.6 billion to repair and replace flood-damaged
infrastructure. SITES-certified landscapes with restored ecosystems, such as wetlands andfloodplains, as well as GI strategies such as bioretention ponds, mitigate flooding by storingand slowly releasing excess water from thunderstorms, hurricanes and other precipitation
events. SITES-certified landscapes that include sand dunes and mangrove forests mitigate
coastal flooding by providing a physical buffer against waves and storm surges. A study foundthat during Hurricane Irma in 2017, mangroves in Florida prevented over $1.5 billion in direct
flood damages and protected the lives of over half a million people.

Xuhui Runway Park | Photo: Insaw Photography

Drought and Heat Mitigation
The risk of droughts and heat waves increases alongside atmospheric temperature rise.
Droughts and heat waves can lead to reduced water flow, water scarcity, soil erosion,
biodiversity loss and increased wildfire risk. This can damage infrastructure, degrade
ecosystems, and cause human illness and death. Of all weather-related events, heat waves
cause the most deaths worldwide. Healthy vegetation promoted by SITES provides shadingand evapotranspiration to reduce heat absorption and air temperature.
Healthy soils are also better at storing water and delivering it to plants. GI strategies such asbioretention ponds and rain gardens retain precipitation and recharge groundwater resources.
In times of droughts and heat waves, healthy ecosystems that retain and conserve water areimportant, especially in urban heat islands that experience significantly hotter temperatures
than surrounding areas.

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Wildfire Mitigation
The frequency of wildfires, length of wildfire seasons and burned area from wildfires are
increasing as the climate gets warmer and drier. Wildfires are also more likely to occur due toland use changes, large-scale insect infestation, poor management practices and fuel loads
that exceed historical conditions. Wildfires cause significant ecological damage and pose
grave threats to human life and property. However, wildfire risk can be greatly reduced bydesigning, building and maintaining sites to better manage fuels. SITES encourages project
teams to create defensible space around structures by planting native fire-resistant plant
species and practicing prescribed burns similar to natural fire regimes. These strategies
manage vegetative biomass and reduce the accumulation of dead, flammable plant material.
Increased biodiversity also helps to decrease fuel loads. For example, burrowing animals stir
up leaf litter, which helps the ground retain moisture and breaks down dead leaves.

Ensuring Future Food Supply
Farmland is ripe for development because it tends to be flat, well drained, open andinexpensive. Once converted to industrial and urban uses, farmland and its value are lostand cannot be regained. Even so, agricultural land is still being converted to urban andhighly developed land nationwide. Between 2001 and 2016, 4 million acres were lost to
the expansion of urban areas. SITES conserves the most productive farmland for future
generations by discouraging projects from building in these areas.
By using native plants, SITES supports habitat for insects, birds, bats and other importantpollinator species that support plant reproduction and crop cultivation. Up to 80% of theworld’s crop plant species depend on pollination by animals, with natural pollination services
soon to be worth over $3 trillion globally. The physical availability of food is important inglobal efforts to reduce the number of people suffering from hunger and malnutrition.

Sedimentation and Erosion Control
Erosion occurs when the health of plant and soil communities is degraded by activities suchas deforestation, overgrazing, chemical pesticide and fertilizer use, and poor construction
practices. Eroded soils may lose fertility as well as their ability to support vegetation, combat
pests and retain water. Erosion also causes sedimentation, which can lead to water pollution,
decreased water quality and reduced stream flow capacity. Both erosion and sedimentation
can worsen the impact of floods and degrade the overall health of ecosystems.
SITES prevents erosion by preserving and restoring the health of plant and soil communities,
which can take decades or even centuries to grow. During construction, SITES projects
control erosion, sedimentation and pollutants. Strategies include mulching, creating sedimenttraps and covering topsoil for reuse. Native plants are also encouraged because their roots
hold the soil in place, absorb the energy of coastal waves, and break up the flow of stream
and river currents that may cause erosion.

George “Doc” Cavalliere Park | Photo: Bill Timmerman, Timmerman Photography

Why SITES? | sustainablesites.org

6BIODIVERSITY
Biodiversity is lost due to habitat exploitation, climate change, pollution and invasive species.
According to the United Nations, ecosystem loss and degradation are the main threats to
85% of all threatened species. Biodiversity is necessary for the conservation of biological andgenetic diversity, as well as the evolutionary processes that support the long-term health andsurvival of the Earth’s many inhabitants. SITES enriches biodiversity through strategies that
protect and restore ecosystems. Additionally, SITES prohibits the use of invasive plants andrequires projects to have an invasive species management plan and to use an integrated pest
management approach.

Ecosystem Conservation and Restoration
Stable ecosystems are critical for protecting and encouraging biodiversity. Likewise,biodiversity is critical in supporting healthy, stable ecosystems. Stable ecosystems withhigh levels of biodiversity provide life-sustaining resources and services, such as fresh
air and water, climate regulation, pollination, soil fertility, food and medicine. They also
protect against extreme weather events and help control carriers of human disease. SITES
discourages projects from building in areas that are undeveloped or that contain vital habitatand resources for threatened and endangered species. Instead, SITES-certified projects areencouraged to build in mutually beneficial areas such as urban sites that have already beendeveloped. Ecosystems are further protected and restored through SITES strategies such as
restoring healthy soils, establishing native vegetation systems and limiting the use of toxic
pesticides. A significant amount of biodiversity can be harbored in SITES-certified projects,
including urban parks, gardens, and restored industrial parks and residential areas. SITES
protects and restores ecosystem complexity and function, enriches biodiversity, and supports
the recovery of individual species populations. For every dollar invested in ecosystem
restoration, it is estimated that economic benefits worth up to $30 USD are created.

Management of Invasive Species
Invasive species adapt easily to new areas, reproduce quickly, outcompete native plant andanimal species, and ultimately cause harm to ecosystems, property and the economy. The
United Nations has declared invasive species a key driver of population decline of threatened
and endangered species, habitat loss and degradation, and illegal trade. Approximately
42% of threatened or endangered species are at risk due to invasive species. Preventing,monitoring and controlling the spread of invasives is also costly. Annually, invasives cost theUnited States $137 billion in damages to crops, fisheries, forests and other resources.
SITES forbids the use of invasive plants on projects and requires projects to have a multiyear
invasive species control and management plan. This ultimately supports a healthy and stableecosystem, as well as enhances the biodiversity of a landscape.

Pest Management
Pest species such as insects and bacteria pose threats to ecosystems and farmland. They
spread disease, consume plant material and cause declines in native species populations.
Pests are combated with chemical pesticides at a global cost of $20 billion annually. However,chemical pesticides lead to water and air pollution, soil contamination, and the unintended
death of additional organisms, all of which can disrupt the function, integrity and resilienceof ecosystems. Chemical pesticides can affect the human nervous, hormone and endocrine
systems. SITES promotes natural methods of pest management rooted in the protection andrestoration of healthy, biodiverse ecosystems. Compared to chemical pesticides, naturally
occurring parasites and predators are estimated to provide 5 to 10 times the amount ofpest control for far cheaper. Some estimates value the overall services provided by healthy
ecosystems, including the service of natural pest management, at as much as $125 to $145
trillion per year.

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M AT E R I A L S + WA S T E
SITES reduces the amount of waste sent to landfills and incinerators through strategies suchas efficient use, reuse, recycling and composting of materials. These methods are encouraged
during construction, renovation and demolition of a project site as well as throughout theentirety of a site’s life cycle. Project teams further reduce the production of waste from SITEScertified landscapes by purchasing sustainable materials from responsible manufacturers.

Waste Diversion and Resource Recovery
Waste produced throughout a project site’s life cycle can lead to water and land pollution,
loss of animal life, and human diseases. When stored in landfills, waste contributes to the
production of carbon dioxide and methane gases, which contribute to climate change.
In 2019, industrial and municipal solid-waste landfills accounted for approximately 17% of
human-related methane emissions, equivalent to the emissions of over 21.6 million passenger
vehicles driven for one year. Without strong environmental parameters, waste incinerators
release pollutants such as particulate matter, acid gases, nitrogen oxides and cancer-causing
dioxins.
SITES encourages project teams to design and construct sites to be altered or retrofitted in
the future. Alterations and retrofits are more economical and less wasteful than the complete
demolition and redevelopment of a site. SITES-certified landscapes are also encouraged toefficiently use, reuse, recycle and compost materials through their entire life. This saves on thecosts of transporting wastes to landfills and incinerators, as well as on the costs of purchasing
new materials such as structures and paving. Additionally, composting vegetation trimmings
and food waste supports nutrient cycling and improves soil health.

Sustainable Purchasing
SITES encourages project teams to look for sustainable production strategies whenpurchasing materials. Strategies include increased energy efficiency, reduced resource
consumption and waste, lowered amounts of embodied carbon, and minimized effects onhuman health and the environment. SITES also discourages the purchase of products madefrom threatened tree species and encourages the purchase of products made with recycledcontent. Products made with recycled content may cost less to manufacture and purchase. Bypurchasing local, sustainable products from responsible suppliers, SITES-certified landscapeteams reduce the amount of energy and resource waste associated with production
processes.

Midtown Park | Photo: Design Workshop

Why SITES? | sustainablesites.org

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H U M A N H E A LT H + W E L L - B E I N G
SITES landscapes promote human health and well-being by regulating the climate, mitigating
natural disasters, and preventing disease and illness. SITES further supports both physicaland mental health by promoting outdoor opportunities for physical activity, restorative andaesthetic experiences, mental restoration, and social interaction.

Physical Well-Being
Trees and other vegetation act as a filter to improve air quality by sequestering carbon
dioxide from the atmosphere, as well as by absorbing other particulates and low-level ozone
and emitting breathable oxygen. Estimated total annual air pollution removal (of ozone,
particulate matter, NO2, SO2 and carbon monoxide) by urban trees across 55 U.S. cities is711,000 metric tons, representing $3.8 billion in public value. In fact, a single acre of tree cover
can remove about 80 to 200 pounds of air pollution per year.
Car-dependent communities without adequate outdoor recreational opportunities discourage
active transportation and physical activity. Physical inactivity is a risk factor for obesity,
diabetes, heart disease and other health threats. SITES promotes physical activity byencouraging playgrounds, walking paths, multimodal transportation routes and proximity to
public transportation. The physical health and well-being of all citizens can be improved by
SITES-certified landscapes that promote activities such as walking, biking and more.

Mental Well-Being
Exposure to nature contributes positively to mental health and well-being by reducing stressand improving cognitive function. One study found that green spaces near schools promoted
cognitive development in children and that adults living in public housing units with more
green space displayed better focus than those with less green space. Physical activity andexercise also support mental well-being by reducing stress and feelings of depression andanxiety.

Orange Mall Green Infrastructure Project at Arizona State University | Photo: Arizona State University

Why SITES? | sustainablesites.org

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COMMUNITY BENEFITSSITES encourages projects to address social equity and improve economic opportunities
in their design and development choices. In doing so, SITES landscapes can contribute tobuilding a more stable and engaged community that reflects the regional and cultural identity.

Community Development
By hosting publicly available events, facilities, amenities and programming, SITES-certified
landscapes bring communities together to inform design and to help create projects that
communities actually need and want. Project sites may host educational workshops, afterschool programs, sporting games or nature tours, or they may simply provide outdoor spaces
where people can gather, eat, work and play together. SITES ensures equitable site use forpeople of all ages and those with disabilities by encouraging landscapes to provide optimumsite accessibility, safety and wayfinding. SITES-certified landscapes are also encouraged to
involve site users and stakeholders to address the landscapes’ effects on local residents andpromote long-term engagement with the community. SITES inspires a stronger sense ofidentity and meaning for project sites by involving the community and protecting significant
historic buildings and other cultural aspects of the landscape.

Food Insecurity Mitigation
By encouraging on-site food production, SITES landscapes combat food insecurity andprovide community engagement and education about food production and nutrition. SITES
landscapes are encouraged to grow essential foods by including on-site vegetable gardens,
community gardens, and native, edible nut and fruit-bearing plants. They are also encouraged
to ensure equitable access by selling or distributing this food to local communities.
Community gardening provides a catalyst for neighborhood and community development
while stimulating social connection, encouraging self-reliance, beautifying neighborhoods andreducing family food budgets. Methods of on-site food production used by SITES-certified
landscapes can also amend degraded soils, use captured rainwater, contribute to composting
efforts and reduce pollution caused by chemical pesticides and fertilizers

Local Economic Stimulation
As SITES-certified landscapes are built, used and enjoyed by visitors, economic benefits arestimulated for local communities. During construction, SITES encourages projects to hire local
workforces and purchase local materials and services. SITES-certified landscapes continue
to provide economic benefits — such as employment, entrepreneurship and improved value
in adjacent properties — throughout their life cycles. Local income and job growth lead toincreased local spending and economic activity, which supports public, social and community
services. SITES further supports local communities by promoting ecotourism, or sustainable
travel to natural areas. Ecotourism allows travelers to visit SITES-certified landscapes andlearn about local environments without causing them harm, all while stimulating local
economies. By capturing economic opportunities that result from site development andproviding these opportunities to residents, SITES-certified landscapes promote the longterm economic sustainability of local families and businesses, ultimately supporting resilient,invigorated communities.

CONCLUSION
By protecting, restoring and generating ecosystem services, the Sustainable SITES Initiative
promotes climate regulation, protects air and water quality, controls flooding, improves
resilience, mitigates risks from potential hazards, enhances biodiversity, conserves resources,
and reduces waste. SITES provides additional benefits for human health and well-being,
community development, and local economic stimulation. A wide range of projects canuse SITES to elevate the value of their landscapes, ultimately benefiting the environment,
property owners and communities.

Why SITES? | sustainablesites.org

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