Greening with Justice: Evaluating Denver’s Urban Green Space Policies Through an Environmental Justice Lens

In an era of rapid urbanization and climate change, urban green spaces such as parks, urban forests, gardens, and other natural areas yield multifaceted benefits in supporting the creation of sustainable and resilient cities.^{^[1]} A network of green spaces, often referred to as green infrastructure, also provides this wide range of benefits, including mitigating urban heat island effect and stormwater runoff, enhancing public health, promoting social cohesion, and driving economic growth. However, research reveals that urban green spaces are inequitably distributed across cities, with wealthier and predominantly white neighborhoods receiving a disproportionate share of these resources, while low-income communities and communities of color are left with comparatively limited access.^{^[2]} This inequity renders green space access an environmental justice issue, requiring innovative strategies that balance ecological sustainability with social equity.^{^[3]} As a result, scholars have called on urban planners to adopt a more balanced approach to green space development, one that pursues ecological goals without sacrificing the social needs of existing communities, a framework described as being “just green enough.”^{^[4]}

Denver, Colorado, exemplifies both the potential benefits and challenges of urban green space development. Situated at the base of the Rocky Mountains, Denver has developed into one of the American West’s most distinctive urban centers, drawing residents and visitors alike with its access to outdoor recreation, cultural institutions, and a lively urban environment.^{^[5]} Since 2016, the City and County of Denver has increasingly relied on green infrastructure to address a range of urban challenges, from managing stormwater and cooling city streets to building more equitable neighborhoods and improving safety for bicyclists and pedestrians.^{^[6]} Denver based its efforts on the recognition that green infrastructure mitigates and adapts to our increasingly changing climate while improving quality of life infrastructure.^{^[7]} For instance, in Colorado, climate change is responsible for varied precipitation patterns, warmer temperatures, more intense wildfires, and poorer air and water quality.^{^[8]} Climate models project that the average temperature will increase by 2.5 degrees Fahrenheit to five degrees Fahrenheit by 2050, which will continue to exacerbate environmental and public health problems.^{^[9]} In response, Denver implemented several planning and regulatory policies designed to expand green infrastructure and improve environmental resilience across the city.^[10]

Despite these efforts, disparities in green space access persist in Denver, particularly in low-income and ethnic minority neighborhoods.^{^[11]} For instance, although lower-income young residents and communities of color in Denver are statistically more likely to live near a park than their wealthier white counterparts, affluent and predominately white neighborhoods have access to far more park acreage per young person, a greater number of high-quality parks, and significantly safer park environments.^{^[12]} These disparities suggest that mere proximity to parks does not guarantee meaningful access for low-income and ethnic minority communities.^{^[13]} This is concerning given the well-documented benefits parks and green spaces provide.

By examining Denver’s successes and challenges, this Note explores how cities can develop green spaces that are not only ecologically beneficial but also socially equitable. Further, this Note underscores the importance of urban green spaces due to their role in creating resilient, sustainable, and equitable cities. Additionally, it calls for strategic legal frameworks and collaborative efforts to guarantee that green spaces remain a central piece of urban development in Denver and beyond.

This Note assesses Denver’s green space policies through the lens of environmental justice scholarship, which has organized the concept around four classical dimensions of justice: (1) distributive justice, which concerns the equitable allocation of environmental benefits and burdens across communities; (2) procedural justice, which addresses whether affected populations have meaningful participation in decisions that shape their environment; (3) recognitional justice, which concerns whether the differing needs, identities, and structural vulnerabilities of affected communities are acknowledged in environmental decision-making; and (4) restorative justice, which focuses on compensating for and repairing past environmental harms through targeted policy action.^[14] This Note’s methodology engages primarily with distributive justice, evaluating whether the benefits of green space investment are reaching the communities that need them most. The Note’s recommendations, however, extend into procedural and restorative terrain, advocating for notable community participation in green space planning and anti-displacement protections that address the historical inequities this analysis documents.^[15] The recognitional dimension remains an important avenue for future inquiry.^[16]

Section II provides a historical and functional overview of urban green spaces, highlighting their environmental, social, health, and economic benefits. Section III reviews the current urban green space policies in Denver, focusing on the successes and limitations of policies such as the Denver GBO, the Denver Parks and Recreation Design Standards, and Colorado Revised Statutes section 24-32-3708.

Section IV outlines the methodology used in this note to assess the effectiveness of urban green space policies. To that end, it utilizes metrics such as the Tree Equity Score and the i-Tree Eco v6 model to measure proxies for policy effectiveness: accessibility and equity, environmental benefits, and economic impacts. To supplement the in-state analysis, case studies from out-of-state cities are also evaluated using the Tree Equity Score and i-Tree Eco v6 model to identify success stories that showcase strategies for improving urban green spaces.

Section V addresses potential counterarguments and challenges to these initiatives, including opposition from developers, on-site pollution, funding constraints, and competing transportation needs. Section VI provides recommendations for improving urban green space development in Denver. These include legal and policy reforms, strategies for implementation, community engagement, and the use of public-private partnerships to ensure that there is equitable and sustainable green space access. Section VII identifies future research directions, emphasizing the need for long-term evaluations of green space impacts, the transferability of successful models, and the potential of public lands for green infrastructure development.

II. Background

Urban green space encompasses all urban land covered by vegetation of any kind, ranging from smaller features such as street trees and green roofs to larger publicly accessible spaces such as parks, playgrounds, and greenways.^{^[17]} A connected network of such spaces is commonly referred to as green infrastructure, defined as “a network of multi-functional green spaces and other green features, urban and rural.”^{^[18]} Tracing the history of these spaces is essential to understand the full range of benefits they provide.

A. Historical Context

The integration of natural elements into urban environments has ancient origins, traceable to the Roman Empire’s deliberate cultivation of green spaces within its cities.^{^[19]} Roman pleasure gardens, known as “horti,” were specifically conceived as spaces where built structure and natural landscape coexisted, offering residents pleasure and a sense of repose.^{^[20]} Drawing on Persian and Greek traditions, these spaces collectively produced a layered system of green areas surrounding the city, ranging from expansive parks on the urban periphery to the private villa gardens of the wealthy, and the smaller cultivated plots of ordinary Romans.^{^[21]} This tradition found its most ambitious expression in the Emperor Nero’s “Domus Aurea,” completed in AD 68, whose grounds embodied the Roman concept of “rus in urbe,” or countryside within the city.^{^[22]} As the historian Suetonius recorded, the palace estate incorporated “various rural tracts of land with vineyards, cornfields, pastures, and forests, teeming with every kind of animal both wild and domesticated.”^[23] The historian Tacitus similarly marveled at “the fields and lakes and the air of solitude” that pervaded the estate’s grounds.^[24]

For centuries after the fall of Rome, urban green space receded from planning priorities, with gardens confined largely to monastic and religious settings.^[25] The 19th century marked a turning point, as industrialization’s toll on urban environment gradually compelled governments and civic organizations to treat public green space as a matter of collective necessity rather than private privilege.^[26] As cities became increasingly overcrowded, polluted, and disconnected from the natural landscape, a growing coalition of civic leaders and philanthropists argued that access to open space was essential to the health and wellbeing of urban populations.^[27] This conviction gave rise to a lasting metaphor: “William Pitt (1708-1778), twice Prime Minister of Great Britain, argued that ‘parks were the lungs of London,’” a phrase later cited in parliamentary proceedings as justification for shielding parks from development and maintaining them as open-air refuges for the public.^[28] The concept gained traction beyond Britain, eventually reaching the United States, where the landscape architect Frederick Law Olmsted drew on it to build public support for urban park development.^[29]

In the United States, the shift toward public parks was further reinforced by the Romantic movement, whose writers and intellectuals celebrated the restorative and spiritual dimensions of nature as an essential counterweight to the stresses of urban and industrial life.^[30] These ideas found practical expression in a nationwide movement that produced expansive park landscapes across American cities in the latter half of the 19th century.^[31] Frederick Law Olmsted and Calvert Vaux’s design for New York’s Central Park, conceived in the 1850s, became the prototype for this movement, incorporating pastoral elements intended to bring rural scenery into the heart of an industrial city.^[32] Central Park in turn became a model for park systems established in cities throughout the United States in the decades that followed.^[33]

However, even these early urban greening efforts reflected and reinforced existing social inequities. The construction of Central Park required the displacement of Seneca Village, a predominately African American neighborhood of property owners, through the exercise of eminent domain.^[34] From its earliest iterations in the American context, the creation of urban green space has thus been entangled with questions of racial and economic justice that persist to the present day.^[35]

The momentum of the 19th century parks movement did not carry uninterrupted into the 20th century. Influential modernist urban planning frameworks, most notably the Charter of Athens promoted by Le Corbusier and the International Congress for Modern Architecture, prioritized automobile traffic and single-use zoning, lamenting that urban open space, described as the “authentic lungs of the city,” had been eroded over two centuries, while simultaneously failing to restore it in practice.^[36] The rapid suburbanization that followed World War II compounded this decline, as populations migrated outward along highway corridors, leaving urban parks underfunded and deteriorating across North America and Europe.^[37] This period represented a sustained low point for urban green space, during which parks across major cities suffered from reduced public use, accumulating maintenance deficits, and increasing public concerns about crime and safety.^[38]

By approximately 1980, however, a countermovement began to take shape. Public-private partnerships formed to restore landmark parks such as New York’s Central Park and Bryant Park, and park planning and management began to reflect a growing sensitivity to ecological values and the broader environmental services that green spaces provide.^[39] Beginning around 1990, park planning and management began to reflect a growing ecological awareness, and in the years that followed, green infrastructure gained increasing prominence as a planning approach attracting attention from researchers, policymakers, and practitioners as cities sought to address the compounding consequences of rapid urbanization and climate change.^[40] This shift reflected a broader evolution in how planners and policymakers understood urban green spaces, no longer simply as aesthetic amenities or pastoral escapes, but as essential infrastructure serving a wide range of human needs, including public health, environmental resilience, economic vitality, and community wellbeing.^[41]

Denver built one of the American West’s most celebrated park systems, even as the city’s green space history remained as marked by inequity as by ambition. The city developed an extensive park and parkway system in the late 19th and early 20th centuries under the influence of the City Beautiful movement, shaped by nationally recognized landscape architects whose work established the physical and aesthetic character of Denver’s early parks.^[42] That legacy of ambition did not translate into equal access for all of Denver’s communities. The Mariposa District, a predominantly Hispanic neighborhood in Denver’s Lincoln Park area, was developed on former brownfields^[43] and was explicitly identified by the EPA as a community with “environmental justice concerns.”^[44] The subsequent redevelopment of the area received significant investment in sustainable green infrastructure.^[45] Despite that investment, the Mariposa District, which recorded a Tree Equity Score of sixty-two as of the date of research, and the adjacent Sun Valley neighborhood together hold Denver’s two lowest Tree Equity Scores.^[46] This geographic concentration of green space inequity exposes the persistent gap between green infrastructure investment and equitable green space outcomes that this Note examines. Denver’s semi-arid climate adds a further layer of complexity unique to the Colorado context. The green landscape aesthetic that defines the city’s historic park system has long depended on substantial water consumption at odds with the region’s natural environment, a tension that will only intensify as climate change tightens pressure on the Colorado River Basin.^[47]

B. Environmental Benefits

Understanding why equitable access to these spaces constitutes an environmental justice imperative requires first examining the concrete benefits that green spaces provide and that communities like Denver’s Mariposa District and Sun Valley are disproportionately denied. Green spaces improve climate resiliency.^{^[48]} Cities like Denver, which experience hot, dry summers, are particularly susceptible to the urban heat island effect. The urban heat island effect is when urban areas become significantly warmer than their rural counterparts due to human activity and the prevalence of heat-absorbing materials like concrete and asphalt.^{^[49]} Urban heat islands can increase urban temperatures by up to 12 degrees Celsius compared to non-urban areas.^{^[50]} Green spaces, especially trees and green roofs, have a cooling effect that can reduce temperatures in urban centers, thus mitigating the heat island effect.^{^[51]} For example, trees can lower ambient temperatures through evapotranspiration—the process by which water moves from the land to the atmosphere—reducing the need for air conditioning and lowering energy consumption.^{^[52]}

Green spaces may also contribute to improved air quality, though the magnitude and reliability of this benefit depend significantly on design, species selection, and placement.^{^[53]} Urban vegetation removes a range of harmful pollutants, including carbon dioxide (CO₂), sulfur dioxide (SO₂), nitrogen oxides (NOx), and particulate matter, contributing to cleaner, healthier air.^{^[54]} This is relevant in cities like Denver, where air quality is often compromised by traffic emissions, industrial activity, and natural wildfire smoke.^{^[55]} Additionally, green infrastructure may also play an indirect role in reducing carbon emissions by making active transportation more attractive.^{^[56]} For instance, vegetation such as tree-lined paths moderates temperature extremes, making walking or biking more appealing in urban areas.^[57] Further, the vegetation also “help[s] keep nearby buildings warmer in winter and cooler in summer, thus reducing building energy use.”^[58]

Green spaces enhance urban biodiversity by providing habitats for a variety of plants, birds, and other wildlife.^{^[59]} Biodiversity refers to the variety of life within a particular habitat or ecosystem.^[60] “Denver is home to many urban wildlife species and has entire functioning ecosystems that support herbivores, omnivores, carnivores, and scavengers alongside people and their pets, vehicles, and buildings.”^{^[61]} Diverse ecosystems are better equipped to withstand environmental stressors, including shifting climate conditions, extreme weather events, and the spread of infectious disease, as biodiversity supports the regulatory functions that keep ecosystems stable and productive.^[62] Enhancing urban biodiversity thus connects local green space planning to the broader project of maintaining the ecosystem functions on which human health and community resilience depend.^[63] Beyond environmental benefits, residents themselves stand to gain.^[64] Research shows that access to green spaces with varied plant and animal life promotes physical activity, may foster social connection, and supports mental well-being, including reduced stress and improved mood.^[65]

Finally, green spaces contribute to stormwater management by intercepting precipitation before it reaches impervious surfaces, removing contaminants that would otherwise enter waterways, and decreasing the overall volume of runoff generated in urban environments.^{^[66]} In a city like Denver, which is subject to both droughts and heavy storms, this function of green spaces is invaluable for maintaining urban resilience.^{^[67]}

C. Social and Health Benefits

Green spaces also generate social and public health benefits that compound their environmental value. Access to nature is linked to better mental health outcomes.^{^[68]} In an urban context, green spaces provide a reprieve from the stress of city life, offering residents a place to relax, exercise, and socialize.^{^[69]} Studies show that proximity to parks and natural areas can reduce symptoms of depression, anxiety, and stress while improving overall well-being.^{^[70]} In Denver, where outdoor activities like hiking, biking, and skiing are central to the lifestyle, green spaces play an essential role in promoting active living and mental wellness.^{^[71]}

Green spaces also foster community engagement and social cohesion.^{^[72]} They serve as public gathering spaces where residents can come together for recreational activities, cultural events, and public celebrations.^{^[73]} In neighborhoods with limited access to such spaces, community ties can become fragmented.^[74] However, well-maintained and accessible parks can act as community hubs, fostering a sense of belonging and ownership among residents.^{^[75]} This is supported by research in the Metropolitan Region of São Paulo, which found that “[i]ncreased levels of community participation were associated with greater access to [urban green spaces] and a reduction in disparities across socio-economic groups.”^[76] Additionally, the study highlighted “[w]hen citizens are actively involved in [urban green space] management, it enhances their sense of ownership and stewardship.”^[77] By offering equitable access to these spaces and empowering residents through participatory management, cities can cultivate both environmental resilience and social equity for their communities.

D. Economic Benefits

The economic benefits of green spaces are significant, particularly in terms of property values and local economies, as research shows that parks and green spaces increase nearby home values, generate substantial tax revenue, and contribute billions of dollars in annual economic activity across the country.^{^[78]} For example, in 2010, Denver’s park system enhanced nearby residential property values by five percent, generating $4.1 million in annual property tax revenue, making green space proximity a significant factor in real estate markets.^{^[79]} Additionally, Trust for Public Land found that properties within 500 feet of Denver’s parks had a combined market value of almost $14.5 billion, with park proximity accounting for approximately $724 million of that total value, demonstrating the substantial premium urban green spaces command in residential real estate markets.^{^[80]} This park proximity premium extends across Denver’s residential real estate market broadly, encompassing a wide range of property types and neighborhoods rather than being confined to high-value areas.^{^[81]}

In addition to improving property values, green spaces contribute to the local economy by supporting tourism.^{^[82]} Denver, known for its proximity to natural attractions such as the Rocky Mountains, leverages its urban parks and outdoor amenities to promote tourism.^{^[83]} “Denver visitors stimulate the local economy and benefit hotels, meeting facilities, attractions, restaurants, art and cultural institutions, tour companies, transportation providers, local farmers, and countless other businesses.”^{^[84]}

Green spaces generate economic savings by reducing the burden on municipal water systems.^{^[85]} Green infrastructure delivers direct municipal savings by intercepting precipitation before it reaches the sewer network because when stormwater is captured or absorbed on-site, cities process less runoff at wastewater treatment facilities and therefore can scale back investment in costly underground conveyance infrastructure.^{^[86]}

Beyond reducing wastewater costs, green infrastructure also provides economic protection against flood damage.^{^[87]} As climate change increases the likelihood of intense precipitation events, both localized flash flooding and overbank riverine flooding are expected to become more frequent challenges for urban communities.^{^[88]} Nature-based stormwater features can reduce the volume of water that accumulates on streets and properties during heavy storms, limiting the physical damage that pooling and seepage cause to homes and infrastructure. ^{^[89]}

Alongside the previous cost-reducing mechanisms, green spaces also reduce healthcare costs.^{^[90]} Research, published in Environment International, found that individuals living in the greenest neighborhoods incurred significantly lower annual healthcare costs than those living in areas with minimal vegetation; the researchers estimated the difference at several hundred dollars per person each year.^{^[91]} The study also found that residents living closest to green space tended to skew toward older, higher-income, and more educated demographic groups, and were more likely to be male and white.^{^[92]} These healthcare savings are not equitably distributed—communities of color are disproportionately excluded from green space access due to historical practices including redlining, displacement, and income-based segregation, meaning the economic benefits of green space accrue primarily to communities that are already advantaged.^[93]

Green infrastructure development also creates employment across a range of skill levels.^{^[94]} For example, in Pennsylvania more than half of green infrastructure workers earn more than $31,200 annually (i.e., fifteen dollars per hour), even among those without a high school diploma or equivalent.^{^[95]} The workforce potential for green infrastructure is substantial, especially when stormwater requirements and funding sources are in place.^{^[96]} From 2011 to 2019, Pennsylvania’s green infrastructure jobs expanded by 9.2 percent, outpacing the state’s overall occupational growth rate of 6.3 percent over the same period.^{^[97]} While this data reflects Pennsylvania’s experience, it illustrates a national pattern of green infrastructure job creation that Denver’s workforce development strategy could replicate at the local level. Having established the breadth of benefits that urban green spaces provide, this Note now turns to examine how Denver’s existing policies are—and are not—delivering those benefits equitably across the city.

III. Current Urban Green Space Policies in Denver

In Colorado, policies regulating urban green spaces focus on balancing growth with environmental sustainability and community health. Denver has implemented several regulatory frameworks to promote green infrastructure development, such as the Denver GBO and the Denver Parks and Recreation (“DPR”) Design Standards. Other Colorado statutes, including Colorado Revised Statutes section 24-32-3708, also contribute to the conservation of open spaces, wildlife habitats, and sustainable urban planning. This section examines the current regulations shaping urban green spaces in Colorado, with a focus on the legal and policy landscape in Denver.

A. Denver Green Buildings Ordinance (“GBO”)

The Denver GBO, enacted in 2018, mandates that new buildings of 25,000 square feet (“sq. ft.”) or larger, as well as major building additions and roof permits for large buildings, incorporate sustainability features.^{^[98]} Developers and property owners must choose from a menu of sustainable building strategies, such as the installation of green roofs, cool roofs, solar energy systems, and energy-efficient designs.^{^[99]} The ordinance’s reach is constrained, however, by a series of exemptions that limit its application to larger developments. The Ordinance does not apply to certain types of buildings, including residential structures like single-family homes, duplexes, or buildings with fewer than three stories.^{^[100]} Additionally, parking structures and temporary buildings are exempt, potentially limiting the ordinance’s impact on overall green space in these areas.^{^[101]} While certain residential developments must meet the cool roof requirement, they are not obligated to adopt other compliance strategies.^{^[102]}

The GBO’s early implementation record demonstrates its contribution to Denver’s green infrastructure. In 2022 alone, the ordinance required 101 newly constructed buildings and forty-eight existing buildings to install cool roofs, with many projects implementing additional compliance strategies such as using green spaces, on-site renewables, and energy efficiency improvements.^{^[103]} As a result, developers installed 35,573 sq. ft. of vegetated roofs, 81,250 sq. ft. of at-grade green space, and 676,424 kWh of solar capacity, thereby making a solid contribution to Denver’s greening efforts.^{^[104]}

Large commercial and office buildings subject to the GBO are disproportionately concentrated in Denver’s downtown core, which contains over 23 million sq. ft. of office space, and affluent neighborhoods like Cherry Creek and the Denver Tech Center.^[105] Meanwhile, lower-income residential areas are characterized by smaller-scale development that falls outside the ordinance’s scope.

The Mariposa District, with a Tree Equity Score of sixty-two at the time of research—among Denver’s lowest—alongside the adjacent Sun Valley neighborhood, exemplifies this disparity.^[106] This predominantly low-income Hispanic community—recognized by the City of Denver in 2021 as a Historic Cultural District honoring the neighborhood’s central role in the Chicano Movement—consists of mixed-income housing redevelopment with individual building phases containing only 5,500 to 11,000 sq. ft. of commercial space.^[107] None of these structures trigger GBO requirements. This means the ordinance’s benefits in stormwater management, roof cooling, and green space expansion remain out of reach for the very residents who need them the most, even as those residents continue to bear disproportionate environmental burdens from inadequate tree canopy, urban heat, and poor air quality.^[108]

The size-based exemption creates a double exclusion. Communities with the greatest need for green infrastructure improvements lack both adequate tree canopy and buildings large enough to mandate GBO compliance.

B. Denver Parks and Recreation Design Standards

The Denver Parks and Recreation Design Standards (“Standards”) serve as a foundational document for ensuring the development of high-quality, publicly accessible urban parks and natural open spaces that align with Denver’s Game Plan for a Healthy City.^{^[109]} Adopted by DPR as a technical and operation manual, the Standards function as an internal planning and design tool that translates the Game Plan’s twenty year vision into concrete physical requirements.^[110] The Standards were developed through collaboration between DPR’s Planning, Design & Construction Director and multiple city departments, including Community Planning and Development and Public Works, following over two years of community input from more than 6,000 Denver residents during the Game Plan development process.^[111]

The Standards apply primarily to DPR-initiated projects and govern how the department designs, constructs, and maintains parks, recreation facilities, and natural open spaces.^[112] They establish specific technical criteria for everything from grading requirements and utility placement to landscape design and accessibility features.^[113] While the Standards are mandatory for all DPR capital projects to ensure consistency across the city’s 280+ urban parks (encompassing nearly 20,000 acres) and thirty recreation centers, they also serve a critical role in guiding private development.^[114]

When private developers propose large-scale projects, particularly those in mixed-use zone districts or requiring General Development Plans, they must coordinate with DPR to ensure any park dedications or public open spaces meet these design standards.^[115] The Standards require developers to dedicate land or create public spaces within large developments, with DPR providing technical guidance on appropriate amenities, environmental impact, and integration within Denver’s broader parks system.^[116] This collaborative approach, enforced through Denver’s zoning code and site plan review process, ensures that privately developed green spaces contribute meaningfully to the city’s interconnected park infrastructure rather than existing as isolated amenities.^[117]

The Standards ensure that new parks and open spaces are accessible to the public and that they meet the diverse needs of Denver’s urban communities by complying with the Americans with Disabilities Act and related accessibility standards.^{^[118]} Building on this foundation of accessibility, the standards should also align closely with Denver’s Game Plan for a Healthy City, making sure that every resident is within a ten minute “walk or roll” to a park.^{^[119]}

The Standards promote a systems-thinking approach that treats parks and open spaces as dynamic components of the city’s broader environmental and social infrastructure.^[120] They also establish a framework for private developer contributions, requiring land dedications or public space creation within large developments.^[121] Ecologically, the Standards prioritize natural resource improvement, wildlife habitat preservation, and climate resilience through green infrastructure, with the goal of reducing urban heat island effects and preparing Denver’s communities for the compounding pressure of climate change.^[122]

C. Colorado Revised Statutes § 24-32-3708

Statewide, Colorado Revised Statutes § 24-32-3708 plays a key role in promoting the preservation of natural land and the expansion of open spaces across urban and rural areas. It states:

(1) No later than December 31, 2025, the director, in consultation with relevant state agencies including the department of agriculture, the division of parks and wildlife in the department of natural resources, the outdoor recreation industry office in the office of economic development, and the Colorado tourism office, shall develop and publish a natural land and agricultural interjurisdictional opportunities report that must include:

(a) Opportunities for local governments and metropolitan planning organizations to achieve connectivity to open space, wildlife habitat, and other priority landscapes;

(b) Opportunities for local governments and metropolitan planning organizations to achieve the preservation of agricultural land, historic and cultural resources, urban parks and green spaces, exurban open spaces, recreational resources, wildlife habitats, and ecosystems with the greatest need for conservation and mitigation of hazards; and

(2) The natural land and agricultural interjurisdictional opportunities report must integrate and include information from relevant state, regional, and local plans that address the subject matters identified in subsection (1) of this section.

This statute requires creating a report identifying opportunities for local governments to connect urban areas to open spaces, wildlife habitats, and other priority landscapes.^{^[123]} It will also outline best practices for conserving urban parks and green spaces, emphasizing the need for urban development to be in harmony with natural conservation efforts.^{^[124]} The statute emphasizes several key critical areas, including collaborating with local governments, connecting urban areas and nature, providing a roadmap for preserving natural and agricultural land while integrating existing plans, and offering practical tools for implementation.^{^[125]}

The statute highlights the importance of collaboration between local governments, urban planners, environmental groups, and other stakeholders to create a cohesive approach to urban green space planning and conservation.^{^[126]} For instance, the statute requires the Executive Director of the Department of Local Affairs to consult with multiple state agencies, including the Department of Agriculture, the Division of Parks and Wildlife, the Outdoor Recreation Industry Office, and the Colorado Tourism Office, to develop a report.^{^[127]} The statute strengthens collaboration with other agencies to ensure holistic involvement in meeting the statute’s preservation goals.^{^[128]}

The subsequent report, prepared by various stakeholders, must identify opportunities for local governments and metropolitan planning organizations to achieve both connectivity and conservation objectives.^{^[129]} Further, the report must identify connectivity opportunities to open spaces, wildlife habitats, and priority landscapes.^{^[130]} Next with regard to conservation, the report must include opportunities relating to the preservation of agricultural land, historic and cultural resources, urban parks, green spaces, exurban open spaces, recreational resources, wildlife habitats, and ecosystems in need of conservation and hazard mitigation. This initiative encourages cities and towns to consider ecological connections when planning urban expansion and development.^{^[131]}

Finally, the report must provide the best practices, tools, and resources to help local governments and metropolitan planning organizations implement the opportunities outlined in the previous paragraph.^{^[132]} This provides stakeholders with an actionable strategy for conservation and connectivity goals.^{^[133]} Moreover, the statute requires the report to integrate information from relevant state, regional, and local plans that address the subject matters identified in the report.^{^[134]} Building upon these initiatives, the following section outlines the methodology used to evaluate the effectiveness of urban green space policies in Denver and beyond, combining quantitative metrics and qualitative case studies to assess accessibility, equity, environmental benefit, and economic impact.

IV. Methodology: Policy Analysis and Case Studies

This section outlines the methodological approach used to evaluate Denver’s urban green initiatives, including the GBO, DPR Standards, and Colorado Revised Statutes section 24-32-3708. Using Tree Equity Score and i-Tree Eco v6 as key metrics, the analysis evaluates policies against three factors: (1) accessibility and equity; (2) environmental benefits; and (3) economic impact. The section then applies these metrics to evaluate Denver’s regulations alongside case studies from Houston, Chicago, and Philadelphia to identify successful strategies and lessons for improving urban green spaces.

A. Metrics for Effectiveness

One critical metric for assessing the factors of accessibility and equity is the Tree Equity Score from American Forests.^{^[135]} The Tree Equity Score is a quantitative tool for evaluating how effectively urban tree canopy serves underserved communities across multiple dimensions of environmental and public health equity. The score ranges from zero to 100, where lower scores indicate greater disparities in access to trees, which have environmental and health benefits.^{^[136]} For context, the Tree Equity Score methodology defines a score of 100 as the point at which a neighborhood has enough trees to meet its canopy goal.^[137] Lower scores reflect both a greater gap between existing and target canopy coverage and a higher concentration of residents who are disproportionately vulnerable to heat exposure, poor air quality, and related health burdens.^[138] A neighborhood score of sixty-two, such as that recorded by Denver’s Mariposa District at the time of research, therefore signals not only a serious shortage of tree canopy but a heightened urgency to address it given the demographic characteristics of the population bearing that shortage.^[139]

The i-Tree Eco v6 model measures the factors of environmental benefit and economic impact. It works by merging tree measurements and field data with pre-processed hourly weather and air pollution data.^{^[140]} The i-Tree model evaluates urban forest structure information—including species composition, density, and health—and quantifies the resulting ecosystem services: pollution removal, carbon sequestration and storage, stormwater runoff reduction, and building energy effects.^[141] It also calculates the public health and economic value of these services, enabling direct comparison of green infrastructure performance across neighborhoods and jurisdictions.^[142]

B. Policy Analysis – Case Study Selection

1. Local Case Studies: Denver Compared to Other Nearby Cities

To provide a nuanced evaluation of green space policies within the Denver area, a range of case studies from nearby cities provide a detailed local analysis of diverse urban green space needs. These cities—Denver, Commerce City, Lakewood, Aurora, Thornton, and Westminster—represent a range of urban contexts, from more densely populated hubs to smaller municipalities. Each of these selections has its own unique challenges and opportunities in relation to urban green space development. Examining these cities provides insight into how Denver compares to other nearby cities within Colorado. Moreover, these cities’ varying Tree Equity Scores and i-Tree values offer insights into the challenges and opportunities in improving green spaces in areas facing higher density and environmental challenges.

Tree Equity Scores
City	Composite Score	Lowest Score
Denver	90	62
Commerce City	78	65
Aurora	92	83
Thornton	87	73
Lakewood	92	83
Westminster	93	78

Figure 1: Detailing the Tree Equity Scores throughout cities near Denver, Colorado.^[143]

Figure 1 reveals a consistent pattern across all six cities: composite Tree Equity Scores substantially overstate equitable canopy access when neighborhood-level data is examined.^[144] Every city in the analysis—including the highest performers, Westminster and Lakewood with composite scores of 93 and 92 respectively, contains neighborhoods where scores drop significantly below the city average, confirming that equity gaps persist even in cities that appear to be performing well by aggregate metrics.^[145] Denver presents the most pronounced disparity, with a composite score of 90 masking a neighborhood of 62—a gap of 28 points that reflects a structural failure to direct canopy investment toward the city’s most vulnerable residents.^[146]

The most acute disparities are concentrated in the cities and neighborhoods where environmental burdens are already the highest.^[147] Denver’s Mariposa District, with its score of 62, exemplifies a pattern seen across the region: communities bearing the greatest heat, air quality, and public health burdens are simultaneously the least served by existing tree canopy.^[148] Commerce City, with both the lowest composite score in the analysis at 78 and documented health burdens from industrial air pollution, presents a similarly urgent case.^[149] This urgency is even more compelling when accompanied by the i-Tree data examined below.^[150]

Denver			Aurora
Tree effect	Environmental Impact	Value ($)	Tree effect	Environmental Impact	Value ($)
Carbon Dioxide Uptake	18,337 tn	1,700,372	Carbon Dioxide Uptake	8,469 tn	785,244
Storm Water Mitigation	272 MG/ yr	553,374	Storm Water Mitigation	77 MG/yr	76,296
Air Pollution Removal	268,481 lb/yr	860,318	Air Pollution Removal	98,331 lb/yr	142,151
Total Value Provided ($)		3,114,064	Total Value Provided ($)		1,003,691
Existing Canopy	4,475 acres		Existing Canopy	2,081 acres
Plantable Space	58,136 acres		Plantable Space	78,540 acres
Increase in Tree Benefit Value by 10% increase in canopy area		141,369	Increase in Tree Benefit Value by 10% increase in canopy area		21,845
Commerce City			Thornton
Tree effect	Environmental Impact	Value ($)	Tree effect	Environmental Impact		Value ($)
Carbon Dioxide Uptake	939 tn	87,152	Carbon Dioxide Uptake	2,185 tn		202,628
Storm Water Mitigation	8 MG/yr	8,203	Storm Water Mitigation	23 MG/yr		37,509
Air Pollution Removal	9,535 lb/yr	4,047	Air Pollution Removal	21,151 lb/yr		18,101
Total Value Provided ($)		99,402	Total Value Provided ($)			258,238
Existing Canopy	231 acres		Existing Canopy	536 acres
Plantable Space	16,150 acres		Plantable Space	15,976 acres
Increase in Tree Benefit Value by 10% increase in canopy area		1,226	Increase in Tree Benefit Value by 10% increase in canopy area			5,560

Lakewood			Westminster
Tree effect	Environmental Impact	Value ($)	Tree effect	Environmental Impact	Value ($)
Carbon Dioxide Uptake	8714 tn	808,091	Carbon Dioxide Uptake	3253 tn	301,659
Storm Water Mitigation	144 MG/yr	205,663	Storm Water Mitigation	44 Mg/yr	66,047
Air Pollution Removal	171,228 lb/yr	444,349	Air Pollution Removal	47,539 lb/yr	96,169
Total Value Provided ($)		1,458,103	Total Value Provided ($)		463,875
Existing Canopy	2,142 acres		Existing Canopy	795 acres
Plantable Space	17,153 acres		Plantable Space	14,353 acres
Increase in Tree Benefit Value by 10% increase in canopy area		65,000	Increase in Tree Benefit Value by 10% increase in canopy area		16,223

Figure 2: The tables above record the data of the i-Tree Eco v6 Model for each respective city. It provides a breakdown of the current tree canopy coverage, potential for expansion, and the environmental and economic benefits that are and could be achieved by increasing tree canopy coverage. Note: tn=tons, MG/yr= million gallons per year, lb/yr = pounds per year.^[151]

The i-Tree data here provides a compelling case in showing the numerous benefits of urban green spaces and, more broadly, green infrastructure. Focusing on Denver’s environmental benefits, its current existing canopy of 4,475 acres delivers many benefits. First, the wood in the trees would sequester 18,337 tons of carbon dioxide, which counteracts the carbon dioxide emissions of 2,817 gasoline powered passenger cars.^[152] Next, the filtration and removal of air pollution by the leaves of trees is annually estimated to avoid one hospital and emergency room (“ER”) visit, reduce acute respiratory symptoms and exacerbated asthma by 387 incidents, and prevent the loss of thirty-three school days.^[153] Finally, the rainfall (272 million gallons per year) absorbed by tree roots and therefore kept out of storm sewers equals the volume of ninety-four Olympic sized pools.^[154] These environmental benefits are not just theoretical, they are quantifiable and actionable, providing a strong rationale for expanding these green space benefits to areas with low access to tree canopies mentioned in the Tree Equity Score analysis.

The economic value of urban green spaces is equally significant here, offering tangible returns on investment. For example, Denver’s trees provide approximately $3.1 million in annual benefits, including $1.7 million from carbon sequestration, $553,374 in stormwater benefits, and $860,318 from air pollution removal.^[155]

One striking insight from the i-Tree data is the underutilization of plantable space in each city, the most notable being Commerce City. Commerce City has 231 acres of existing tree canopy.^[156] Further, the city has 16,150 acres of plantable space, representing a massive opportunity for expansion.^[157] To put this into perspective, only roughly 1.4 percent of Commerce City’s plantable space is currently utilized for tree canopy.^[158] This underutilization is shocking considering that Commerce City “has higher fine particle pollution and more serious respiratory problems than the rest of the state.”^{^[159]} Additionally, this finding is disturbing because Commerce City is home to oil refinery work, most notably the Suncor refinery, which has repeatedly broken federal air pollution regulations, thus directly contributing to these serious respiratory problems.^[160] Expanding the canopy in each of these cities, especially Commerce City, could significantly improve air quality and by extension public health.

It is important to note that pollution does not adhere to city boundaries. The EPA found that traffic-related air pollutants reach their highest concentrations at or near major roads, with the zone of influence varying based on traffic volume, meteorological conditions, topography, and nearby land use.^{^[161]} While near-roadway research captures pollution dynamics at a localized scale, the United Nations Office for Disaster Risk Reduction has recognized that atmospheric conditions can carry point source pollutants well beyond their immediate surroundings, placing communities at significant distances from the original emission source at risk.^[162] The Colorado Department of Public Health and Environment has similarly recognized that the pollutants responsible for regional haze are capable of traveling across large geographic areas, with their effects on visibility and air quality extending to hundreds of miles from the original emission source.^{^[163]} Taken together and given that Commerce City is approximately nine miles from Denver, these authorities support the conclusion that emissions from its industrial activities and roadways can meaningfully affect Denver’s air quality. This interconnectedness underscores the need for regional collaboration in tackling air pollution and expanding green infrastructure.

2. Out-of-State Case Studies

To gain broader insights, this Note analyzes case studies from cities such as Houston, Chicago, and Philadelphia due to their similar environmental challenges. Key examples include Bayou at Midtown in Houston, the Chicago Region Tree Initiative, and Philadelphia’s Pollinator Garden initiative.

a. Bayou at Midtown Park, Houston, Texas

Over the last fifty years, there have been many attempts to revitalize Midtown.^{^[164]} The absence of a distinct neighborhood identity, combined with the deteriorating infrastructure, drove businesses out of the district and toward less expensive suburban alternatives.^{^[165]} Community-driven organization in the 1990s led to the establishment of the Midtown Redevelopment Authority (“MRA”), a body created to champion the long-term economic and social vitality of the Midtown district.^{^[166]} Shortly after its formation, the MRA successfully lobbied the city to designate Midtown as an arts and entertainment district, securing Tax Increment Reinvest Zone (“TIRZ”) funding as a financial mechanism to support the district’s revitalization.^{^[167]} A TIRZ operates as a public financing mechanism through which local governments fund physical and infrastructure improvements within a designated geographic zone.^{^[168]} The primary goals of such improvements are to strengthen the economic foundation of existing businesses already operating in the area and to create conditions favorable for drawing in new commercial investment.^{^[169]} With its strategic location, newly secured TIRZ funding, and formal arts and entertainment designation in place, Midtown was well positioned to undergo meaningful transformation and realize its long-dormant potential as a vibrant urban district.^{^[170]}

In 2010, a comprehensive revitalization initiative was launched through the commissioning of a Livable Center Study, which aimed to identify actionable strategies for reinvigorating the Midtown District.^{^[171]} Building on the study’s finding, the design team developed a comprehensive vision plan that outlined specific urban design strategies and pilot initiatives aimed at tackling the district’s social, environmental, and economic challenges while simultaneously elevating its cultural and artistic identity.^{^[172]} The vision plan further addressed two of Houston’s most persistent structural challenges, namely its lack of formal zoning regulations and its deteriorating infrastructure, by offering targeted recommendations for navigating both constraints.^{^[173]} Through this planning process, the design team determined that successful implementation of transformative projects in the district would depend fundamentally on two core principles: fostering a strong sense of place and building long-term environmental and structural resilience.^{^[174]}

Bayou at Midtown Park in Houston is a transformative urban green space that revitalized a previously neglected six-acre “superblock” in the Midtown district, once an “inhospitable urban environment with few amenities.”^{^[175]} The park, built above an underground parking garage, features a multi-purpose lawn, trails, a marketplace, restaurants, an arts garden, a dog park, and social game courts all designed to create a vibrant, pedestrian-oriented, mixed-use hub.^{^[176]}

A key feature of Midtown Park is the “bayou,” a water detention channel engineered to replicate Houston’s natural wetlands, integrating a 70,000-gallon underground cistern that captures stormwater for on-site reuse in irrigation and recirculation; only when excess water accumulates does an overflow structure route it through the Bayou’s native plantings and soils for treatment prior to discharge into the municipal sewer system.^{^[177]} Bayou “has treated 132,000 gallons of water (as of 2022) and protects against flooding during major rainfall events.”^{^[178]} To overcome the challenge of growing trees above a parking garage in relation to nutrients, the park’s design featured the use of Silva Cells (i.e., a patented, modular, suspended pavement system that integrates water, soil, and tree roots and delivers on-site stormwater management through bioretention), providing adequate soil volume and structural support for those trees.^{^[179]}

Due to the innovativeness of the park’s design, Midtown Park represents sustainability and resilience in one of the nation’s largest and most diverse cities.^{^[180]} Moreover, it has earned “SITES Silver certification” and numerous awards, including the “ASLA National Honor Award,” for its “innovative design features” and “commitment to the responsible use of resources.”^{^[181]} The park transformed Midtown into Houston’s “most walkable neighborhood,” serving as a “premier park destination” for residents and visitors alike.^{^[182]} Now, this Note turns to the quantitative analysis of Midtown.

Tree Equity Scores
City	Composite Score	Lowest Score
Houston	90	64

Figure 3: Report on Tree Equity Score for Houston, Texas.^[183]

The Tree Equity Scores for Houston and Denver reveal a common pattern. While composite tree canopy coverage may appear adequate, localized disparities in access are still very present. Addressing these inequities requires even more targeted investments and innovative green infrastructure solutions such as Bayou at Midtown Park within these lower scored areas. Imperative to understanding the Bayou at Midtown Park’s effect, this Note now turns to Houston’s i-Tree values.

Houston
Tree effect	Environmental Impact	Value ($)
Carbon Dioxide Uptake	482,431 tn	44,734,522
Storm Water Mitigation	7,576 MG/yr	17,415,759
Air Pollution Removal	6,216,273 lb/yr	30,434,111
Total Value Provided ($)		92,584,392
Existing Canopy	83,223 acres
Plantable Space	144,113 acres
Increase in Tree Benefit Value by 10% increase in canopy area		$4,784,986

Figure 4: The table above records the data of the i-Tree Eco v6 Model for Houston, Texas. It provides a breakdown of the current tree canopy coverage, potential for expansion, and the environmental and economic benefits that are and could be achieved by increasing tree canopy coverage. Note: tn=tons, MG/yr= million gallons per year, lb/yr = pounds per year.^[184]

The I-Tree data for Houston paints a vivid picture of the transformative power of urban trees, showcasing their environmental and economic benefits in striking detail. With 83,223 acres of existing canopy, Houston’s trees are environmental superheroes, sequestering a staggering 482,431 tons of carbon dioxide annually—enough to neutralize the emissions of 74,110 gasoline-powered passenger cars.^[185] The benefits do not stop there. The leaves of these trees act as nature’s air filters, scrubbing 6,216,273 pounds of pollutants from the air each year.^[186] This natural filtration system is estimated to prevent 90 hospital and ER visits and slash 10,490 incidents of acute respiratory symptoms and exacerbated asthma annually.^[187] When it rains, Houston’s trees step up again, absorbing 7,576 million gallons of stormwater annually—equivalent to 2,953 Olympic-sized swimming pools—helping to keep floodwaters at bay and easing the strain on the city’s stormwater infrastructure.^[188] These aren’t just abstract numbers; they are real-world impacts that show the indispensable role of trees in creating a healthier, more resilient city.

The economic value of Houston’s trees is equally impressive, delivering $92,584,392 in total value to the city.^[189] Especially important to note is that Houston covered a significant portion of its 144,113 acres of plantable space.^[190] By extension, a ten percent increase in canopy coverage would provide an additional $4.8 million in annual benefits, making expansion of green infrastructure more than just an environmental initiative, but a smart economic strategy.^[191]

b. Chicago Region Trees Initiative, Chicago, Illinois

Another illustrative example is the Chicago Region Trees Initiative (“CRTI”), an urban and community forestry program administered by the Morton Arboretum that works to enhance the well-being of residents across the Chicago region and Illinois by promoting healthier, more diverse, and more equitably distributed tree canopies.^{^[192]} In particular, the initiative focuses on four key priorities: (1) inspiring people to value trees; (2) increasing the region’s tree canopy; (3) reducing threats to urban trees; and (4) enhancing oak ecosystems.^{^[193]} Further, this program “is a partnership of more than 200 organizations across the seven-county Chicago metro region.”^{^[194]}

This initiative was made in response to the Chicago region facing a decline in its urban forest. Chicago had gone from twenty percent in 2010 to eighteen percent in 2020.^{^[195]} For instance, since 2010, the Chicago region lost thirteen million trees to emerald ash borers, an invasive species of insect that is highly destructive to trees.^{^[196]} The Chicago region’s urban forest suffers from significant deficiencies in both species variety and age distribution, with nearly three quarters of all trees measuring less than six inches in diameter, reflecting a canopy heavily skewed toward younger, smaller specimens.^{^[197]} Compounding these challenges, the region’s native ecosystems are no longer self-sustaining and have been reduced to scattered and disconnected patches, with only seventeen percent of those systems remaining.^{^[198]} To combat these deficiencies, the CRTI has committed to a comprehensive strategy focused on improving the overall health of the regional tree canopy, expanding its size, broadening its ecological variety, and guaranteeing that its benefits reach all communities across the Chicago region equitably.^{^[199]}

The CRTI approach is rooted in extensive cross-sector collaboration, leveraging the knowledge and experience of a wide range of partner organizations and individuals to advance its urban forestry goals.^{^[200]} These include diverse stakeholders such as local planning organizations, conservation districts, watershed agencies, universities, and neighborhood groups.^{^[201]} Grounded in scientific methodology, the CRTI has assembled one of the most comprehensive tree canopy datasets, integrating it with information on community demographics, environmental conditions, and public health outcomes to build an evidence-based foundation for its long-term Master Plan extending through 2050.^{^[202]} This data driven approach helps CRTI prioritize communities with the greatest need for investment in trees.^{^[203]}

CRTI’s work includes building municipal capacity for tree care, fostering partnerships across sectors, training community stewards, and providing science-based guidance for action.^{^[204]} CRTI operates across a wide range of programming focus areas while also offering practical support to help communities secure funding and carry out tree planting efforts.^{^[205]} CRTI also provides “data and maps of tree canopy distribution across the region that prioritizes communities with the greatest need for more investment in trees.”^{^[206]} Beyond its planning and research functions, the CRTI also delivers community-facing programming, including an ambassador initiative that provides Chicago residents and community groups with training resources, and funding to lead local tree planting efforts and foster grassroots support for trees.^{^[207]} Now, this Note turns to the quantitative analysis of CRTI.

Tree Equity Scores
City	Composite Score	Lowest Score
Chicago	87	56

Figure 5: Tree Equity Score for Chicago, Illinois.^[208]

Again, there is a common pattern in the Tree Equity Scores between Denver and this out of state case study, Chicago. While composite tree canopy coverage may appear adequate, localized disparities in tree canopy coverage are still very present. Specifically, North Chicago has significantly higher scores overall than South Chicago.^[209] However, there are some patches of better scored areas spread out in southern Chicago, potentially signaling a positive direction.^[210] Nevertheless, this still shows that there is much work left to be done in terms of equitable access to trees and therefore urban green spaces. Just as critical as it was in the prior section, this note now addresses Chicago’s i-Tree values.

Chicago
Tree effect	Environmental Impact	Value ($)
Carbon Dioxide Uptake	50,357 tn	4,669,422
Storm Water Mitigation	664 MG/yr	2,063,426
Air Pollution Removal	492363 lb/yr	7,003,142
Total Value Provided ($)		13,735,990
Existing Canopy	8,804 acres
Plantable Space	47,505 acres
Increase in Tree Benefit Value by 10% increase in canopy area		906,658

Figure 6: The table above records the data of the i-Tree Eco v6

Model for Chicago, Illinois. It provides a breakdown of the current tree canopy coverage, potential for expansion, and the environmental and economic benefits that are and could be achieved by increasing tree canopy coverage. Note: tn=tons, MG/yr= million gallons per year, lb/yr = pounds per year.^[211]

Chicago’s urban tree canopy provides another example of how green infrastructure can deliver both environmental and economic benefits, while also addressing critical public health and equity challenges. The city’s trees sequester 50,357 tons of carbon dioxide annually, equivalent to offsetting the emissions of 7,736 gasoline-powered passenger cars.^[212] The filtration and removal of air pollution by the leaves of trees is estimated to avoid three hospital and ER visits, reduce acute respiratory symptoms and exacerbated asthma by 1,506 incidents, and prevent the loss of 155 school days and thirty-five workdays annually.^[213] Furthermore, the city’s trees absorb 664 million gallons of stormwater annually, equivalent to 350 Olympic sized pools.^[214]

These environmental benefits transform into a total annual value of $13.7 million, representing a good return on investment. This is accomplished despite the existing canopy only covering 18.5 percent of the plantable space still available.^[215] Furthermore, with 47,505 acres of plantable space still available, a ten percent increase in canopy coverage could generate an additional $906,658 in annual benefits making this a worthwhile incentive to continue to invest in green space.^[216]

c. Philadelphia Pollinator Garden, Philadelphia, Pennsylvania

In a collaborative effort launched in 2019, the National Wildlife Federation partnered with the Pennsylvania Horticultural Society to convert twenty-six underutilized vacant lots scattered across West and Northwest Philadelphia into fifty native pollinator gardens designed to withstand the pressures of a changing climate.^{^[217]} These pollinator gardens serve multiple ecological functions simultaneously, strengthening habitat connectivity and species variety throughout the urban landscape, helping to buffer against climate related stressors such as extreme heat and flooding, and providing critical resting points for migratory pollinators whose presence bolsters local biodiversity and overall ecosystem health.^{^[218]}

These gardens are important because they support the survival of pollinators and thus support plant life within the areas they reside.^{^[219]} Pollinators come in many different shapes and sizes, including insects such as honey bees, bumblebees, pollen wasps, ants, butterflies, moths, birds, bats, and more.^{^[220]} Pollinators perform this essential function continuously, serving as indispensable contributors to both broader ecosystem health and agricultural systems that underpin food production.^{^[221]} Their ecological contributions are substantial, being responsible for the pollination of more than three quarters of all flowering plant species and enabling the production of approximately one third of the food and beverages that humans consume.^{^[222]} This initiative is also critical to implement because studies show that honey bees and some wild pollinators are on the decline in North America.^{^[223]} The causes of pollinator decline vary depending on the type of population affected.^[224] Wild pollinator communities have suffered primarily as a result of shrinking and deteriorating natural habitats, whereas populations of managed bees face a distinct threat in the form of illness caused by non-native parasite sand disease-causing organisms introduced into their environments.^{^[225]}

Beyond supporting local pollinators, this initiative provides community and other ecological benefits. Converting underutilized urban land into thriving green space yields benefits that extend well beyond ecology, encompassing improvements to community health, new workforce development opportunities, and progress toward more sustainable models of urban growth.^{^[226]}

To advance pollinator sustainability and by extension the health of the broader plant ecosystem, the initiative’s researchers carefully selected thirteen native plant species and distributed them across the vacant lot sites in randomized quantities to test their relative effectiveness under real urban conditions.^{^[227]} To support continuous pollinator activity throughout the growing season, the project incorporated thirteen native plant species selected in part for their varied flowering periods.^[228] Diversifying bloom times across spring, summer, and fall effectively transforms a pollinator garden from a briefly productive space into a sustained habitat that supports pollinators throughout the entire growing season.^{^[229]} Now, this note turns to the quantitative analysis of the Philadelphia Pollinator Gardens.

Tree Equity Scores
City	Composite Score	Lowest Score
Philadelphia	85	55

Figure 7: Tree Equity Score for Philadelphia, Pennsylvania.^[230]

Yet again, there is a common pattern in the Tree Equity Scores between Denver and this out of state case study, Philadelphia. While composite tree canopy coverage may appear adequate, localized disparities in access are present. Specifically, Northeast Philadelphia remains heavily burdened by inequitable access to tree canopies.^[231] Therefore, there is much more work left to be done in terms of equitable access to trees in this out-of-state case study. Just as before, this Note now turns to analyze Philadelphia’s i-Tree values.

Philadelphia
Tree effect	Environmental Impact	Value ($)
Carbon Dioxide Uptake	56,792 tn	5,266,129
Storm Water Mitigation	946 MG/yr	2,525,037
Air Pollution Removal	653,259 lb/yr	10,994,463
Total Value Provided ($)		18,785,629
Existing Canopy	11,265 acres
Plantable Space	30,786 acres
Increase in Tree Benefit Value by 10% increase in canopy area		1,351,850

Figure 8: The table above records the data of the i-Tree Eco v6 Model for Philadelphia, Pennsylvania. It provides a breakdown of the current tree canopy coverage, potential for expansion, and the environmental and economic benefits that are and could be achieved by increasing tree canopy coverage. Note: tn=tons, MG/yr= million gallons per year, lb/yr = pounds per year.^[232]

Philadelphia’s urban tree canopy provides another strong example of how green infrastructure can deliver both environmental and economic benefits. The city’s trees sequester 56,792 tons of carbon dioxide annually, equivalent to offsetting the emissions of 8,724 gasoline-powered passenger cars.^[233] The filtration and removal of air pollution by the leaves of trees is estimated to avoid four hospital and ER visits, reduce acute respiratory symptoms and exacerbated asthma by 3,279 incidents, and prevent the loss of thirty-five workdays annually.^[234] Furthermore, the city’s trees absorb 946 million gallons of stormwater annually, equivalent to 428 Olympic-sized pools.^[235]

These environmental benefits translate into a total annual value of $18.8 million. Further, by increasing its existing canopy by ten percent Philadelphia can generate an additional $1.35 million in annual value, thereby, providing worthwhile investment and incentive for developing more tree canopy within the city.

These out-of-state cases serve as models for cities in Colorado looking to expand green spaces while addressing broader environmental and social challenges.

C. Evaluation of Policy Effectiveness

The integration of water management features in the Bayou at Midtown Park could serve as an inspiration for Denver’s Standards, with necessary adaptations for climate differences. Houston receives approximately 45 inches of annual precipitation in a humid subtropical climate, while Denver’s semi-arid environment receives only around 15 inches and faces significant drought risk.^[236] Despite these contrasts, Denver could strategically adapt Houston’s green infrastructure approach by incorporating drought-resistant bioswales and rain gardens designed to capture Denver’s intense but infrequent precipitation events, specifically in summer monsoons, rather than consistent rainfall.^[237] By using native, drought-tolerant species in these features, Denver can enhance flood resilience during heavy rainfall, reduce urban heat island effect, and comply with environmental regulations tied to water conservation and habitat restoration, all in alignment with Colorado Statutes.

The Chicago Region Trees Initiative’s focus on the equitable distribution of trees is a valuable model for Denver. Denver can draw from the Chicago model by strengthening its partnerships with community organizations, local government, and the green industry to improve tree planting and maintenance, focusing particularly on underserved areas where green space access is limited.

Philadelphia’s pollinator gardens have transformed vacant lots into spaces that promote biodiversity while addressing urban heat and flooding. Denver’s green spaces could be further developed by incorporating native species and pollinator gardens to not only beautify, but also improve air quality and enhance water filtration—key aspects of Denver’s urban sustainability goals.

By integrating the Denver Parks & Recreation Design Standards and Colorado Revised Statutes with successful case studies, Denver policy makers can gain a more comprehensive understanding of how urban greening policies can shape sustainable, resilient cities. Denver’s green infrastructure initiatives, such as the GBO and tree equity measures, align with these standards, but there are opportunities for expansion and improvements, specifically, through better community engagement, broader compliance incentives, and enhanced ecological connections. Yet before addressing implementation challenges, it must be scrutinized whether these policies are achieving their equity goals. A comparative analysis of Tree Equity Scores and i-Tree Eco data reveals stark disparities between intent and outcome—exposing how even well-designed policies falter in practice.

The Tree Equity Score and i-Tree Eco v6 Model offer complementary but distinct lenses to evaluate urban green spaces—one measuring who benefits, the other quantifying how much. While Tree Equity exposes stark disparities in canopy distribution (for example, Denver’s Mariposa District scoring sixty-two versus affluent areas nearing 100), i-Tree’s dollar-value metrics reveal the tangible costs of those gaps. For instance, Denver’s existing canopy provides $3.1 million in annual benefits, yet low-equity neighborhoods miss out on critical air pollution reduction (avoiding 387 asthma incidents/year) and stormwater mitigation (272 million gallons absorbed). Tree Equity reflects systemic neglect—historical underinvestment in minority communities—while i-Tree’s economic valuations expose the fiscal folly of that neglect.

Trends across cities reveal recurring blind spots. Composite Tree Equity Scores often mask localized inequities: Chicago’s eighty-seven overall drops to fifty-six in South Side neighborhoods; Philadelphia’s eighty-five plummets to fifty-five in Northeast communities. Meanwhile, i-Tree data shows these same areas have untapped potential—Commerce City, for example, uses merely 1.4 percent of its plantable space despite suffering Colorado’s worst respiratory rates.^{^[238]} The discrepancy suggests a failure to translate ecological capacity (what is possible) into equitable access (who gets it). Speculatively, this stems from prioritizing “easy wins,” planting in already-green, higher-income zones where soil quality and political support simplify projects, while deprioritizing marginalized areas with contaminated soils or bureaucratic hurdles.

This is not merely inefficiency—it is environmental injustice. When low Tree Equity Scores correlate with higher heat vulnerability and pollution exposure, green space becomes a lifeline, not a luxury. The i-Tree data proves the return on investment is there: every 10 percent canopy increase in Philadelphia yields $1.35 million in benefits, yet previously identified neighborhoods remain starved for investment. To fix this, cities must utilize Tree Equity as a baseline metric for funding, tying i-Tree’s economic incentives (e.g., stormwater savings) to targeted planting in high-need areas. Otherwise, urban greening risks becoming another wedge, where the privileged reap cleaner air, cooler streets, and higher property values, while marginalized communities inherit concrete and heat. However, as this is considered, it is important to also address the potential counterarguments and challenges that may arise in the process of implementing these strategies in Denver’s urban landscape.

V. Counterarguments & Challenges

While the potential for urban greening initiatives in Denver is promising, there are several challenges and counterarguments that need to be addressed to successfully implement these projects. These challenges span economic, physical, social, and collaborative dimensions, each requiring targeted responses that this section examines in turn.

One of the most persistent challenges facing urban greening initiatives is the economic pressure exerted by competing land uses, as the financial returns associated with residential and commercial development consistently position green space provision as a lower priority in urban planning decisions.^{^[239]} Outside of the physical and economic obstacles, the social dimensions of urban greening projects, namely how community members perceive the safety of a space, its vulnerability to vandalism, and the general fear of crime in the surrounding area, can prove equally decisive of whether a greening initiative ultimately succeeds.^{^[240]}

Educating developers, property owners, and the public about the positive impacts of urban greening, such as improved air quality, reduced heat islands, and stronger community well-being, can help build support for these projects.^{^[241]} Defining achievable objectives for each project and incorporating them into a broader planning framework can also help align these initiatives with the goals of various stakeholders. Research shows that public knowledge is an important element in the adoption of infrastructure strategies and the enhancement of resilience.^{^[242]} A nationally representative survey of nearly one thousand United States residents found a striking knowledge deficit among non-experts, with fewer than one quarter correctly identifying social infrastructure and fewer than one in five accurately describing green infrastructure.^{^[243]} To close this gap, recommend integrating green and social infrastructure concepts into both formal school curricula and community outreach programs.^{^[244]}

Another critical challenge these initiatives face is that sites that are earmarked for green development often suffer from physical challenges, such as soil compaction, or chemical issues, such as contamination.^{^[245]} These problems must be addressed before vegetation can be successfully established. Further, soil contamination creates major obstacles for development projects, as remediation is often costly and time-consuming. ^{^[246]} For example, projects facing soil contamination find themselves stuck with additional costs and delays that hinder the start of investments and construction efforts—factors that together discourage short-term-focused developers from pursuing contaminated properties as viable development opportunities.^{^[247]}

Taking inspiration from the Bayou at Midtown Park, a way to remedy this would be to use scientific innovations, such as the Silva Cells, to help improve soil quality to grow vegetation. For instance, to address the challenge of sustaining healthy tree growth above an underground parking structure where access to natural soil is severely limited, the project incorporated Silva Cell, a modular soil management system that creates sufficient underground soil volume while simultaneously bearing the load of the pedestrian surfaces above.^{^[248]} Other potential solutions to the issue of soil compaction and contamination would be to select appropriate remediation techniques such as bioremediation, a method that deploys naturally occurring microorganisms to neutralize organic pollutants, and soil washing, a process that extracts contaminants from soil using water or chemical agents.^{^[249]} Where contamination levels are severe or pose an immediate threat, physically removing and relocating the affected soil entirely can serve as a rapid and direct intervention to eliminate risk at the source.^{^[250]}

The viability of newly established green spaces is also shaped by broader environmental conditions, including the ambient air quality surrounding a site and how well it connects to the existing network of green infrastructure in the surrounding area.^{^[251]} Addressing air pollution at its origin, by curtailing the emissions that generate it in the first place, represents the single most powerful strategy available for safeguarding urban ecosystems from pollution-related degradation.^{^[252]}

Another challenge is the lack of collaboration and communication among stakeholders. Research from a Swedish example highlights this dynamic—weak collaboration and communication were found to exist among various Swedish municipal departments, which created a barrier to integrating green initiatives throughout.^{^[253]} Further, when each department concentrated solely on its own area of expertise, they tended to neglect matters falling outside their professional scope, such as green qualities.^{^[254]} When municipal planners lack a thorough understanding of the ecological and social value that existing green spaces provide, the resulting information deficit undermines the quality of land use decisions and can generate friction between those responsible for planning and those responsible on development.^{^[255]} These conflicts were also partially fueled by developers prioritizing short-term economic gains over long-term environmental and social benefits.^{^[256]}

To overcome these obstacles, planning frameworks must cultivate stronger cross-sector dialogue and cooperative relationships among all relevant stakeholders, ensuring that the preservation and improvement of green qualities receives worthwhile weight alongside competing development priorities.^{^[257]} When such collaborative structures are in place, they can also help bridge the knowledge gaps that currently leave planners without adequate information about the ecological and social value of the green spaces at stake.^{^[258]}

Securing funding and resources represents a persistent obstacle to urban greening projects. As budgets at the federal, state, and city levels become increasingly constrained, there is growing pressure to maximize the use of available land for productive purposes.^{^[259]} City planners often view housing or commercial real estate as more financially beneficial, and as such, may prioritize these developments over green spaces.^{^[260]} Despite their environmental and social benefits, green spaces’ financial returns are often difficult to quantify and justify in competitive economic environments.^{^[261]}

Denver should emphasize long-term, tangible benefits of green spaces to build the economic case for investment.^{^[262]} While the initial cost may be higher, the environmental advantages—such as reducing air pollution, cooling urban areas, and improving stormwater management—can save money in the long run by reducing healthcare costs, flood damage, and energy consumption.^{^[263]} Green spaces also contribute to increased property values and tourism, which can provide additional economic returns.^[264] These long-term benefits can be monetized and used to justify the investment in urban greening initiatives.

Perhaps the most paradoxical challenge facing urban greening initiatives is the risk that green investment itself becomes a driver of the very inequity it is designed to address. Scholars have identified this dynamic as green gentrification. The term describes the process by which environmental remediation and green space improvements increase neighborhood desirability and property values, ultimately displacing the low-income residents and communities of color who most need those improvements and who often fought hardest to secure them.^[265] Studies have documented a consistent pattern in which polluted urban sites experience suppressed property values, followed by material appreciation once remediation is achieved.^[266] This pattern can rapidly price out the longtime residents the cleanup was meant to benefit.^[267]

This risk is not theoretical in Denver. The Urban Displacement Project found that roughly two-thirds of Denver neighborhoods saw housing costs rise sharply between 2000 and 2017, with over fifty thousand low-income Denver households—eleven percent of that population—residing in areas actively dealing with or vulnerable to gentrification-driven displacement.^[268] This burden falls most heavily on communities of color in southwest Denver.^[269] The Mariposa District demonstrates this paradox in sharp relief: significant EPA-funded green infrastructure investment has already occurred there, while the broader La Alma Lincoln Park neighborhood—a Historic Cultural District celebrating the Chicano Movement—is nonetheless actively experiencing rising home prices and the displacement of longtime residents, community leaders, and activists.^[270] These dynamics suggest that green space investment without deliberate anti-displacement protections risks producing outcomes that are environmentally improved but socially unjust.^[271]

Addressing green gentrification requires a coordinated set of anti-displacement strategies implemented in tandem with green infrastructure investment rather than as an afterthought.^[272] No single policy is sufficient on its own. Inclusionary zoning requirements, while useful, do not confront the core displacement dynamic: affordable units in new developments are often occupied by lower-income newcomers rather than protecting the longtime residents most at risk of being pushed out.^[273] More targeted approaches include community land trusts, which preserve long-term affordability for existing residents; right-of-first-refusal policies, which provide tenants and community organizations an opportunity to purchase properties before outside investors; and tenant protections such as anti-eviction ordinances and property tax rebates that help anchor residents whose housing costs rise in the wake of nearby investment.^[274]

Beyond housing policy, cultural preservation efforts such as supporting locally owned businesses, funding community arts organizations, and recognizing the historical and cultural significance of neighborhoods like La Alma Lincoln Park also serve as anti-displacement tools by anchoring community identity in ways that resist erasure even as demographics shift.^[275]

Transportation infrastructure represents another competing priority that can displace urban green space investment. Urban mobility is essential for the movement of people and goods, and it is often seen as a more pressing priority than the development of green spaces.^{^[276]} Efficient transportation systems enable people to access schools, work, services, and facilitate the smooth functioning of cities.^{^[277]} The need for effective urban mobility solutions can often overshadow the push for more green spaces, as the perceived benefits of transportation infrastructure are more immediate and tangible.^{^[278]}

Denver can navigate this tension by framing green infrastructure and sustainable transportation as complementary rather than competing priorities. Green spaces reduce the air quality burden imposed by vehicle emissions, while tree-lined streetscapes and shaded pedestrian paths make active transportation more appealing, thereby reducing vehicle miles traveled and their associated emissions.^{^[279]} Investing in bike lanes, protected pedestrian infrastructure, and transit access adjacent to green spaces can reinforce both goals simultaneously, advancing Denver’s urban sustainability objectives without treating mobility and greening as zero-sum choices.^{^[280]}

VI. Recommendations

To push Denver’s urban green space development forward, Denver must tackle the gaps and challenges it may face head-on. This can be done by drawing from the lessons of out of state case studies, like Houston’s Bayou at Midtown Park, Chicago’s Region Trees Initiative (“CRTI”), and Philadelphia’s Pollinator Gardens. These examples showcase both the potentials and the pitfalls of urban greening initiatives, offering a roadmap for Denver to follow while addressing its own unique issues.

A. Legal and Policy Reforms

Denver’s path toward equitable and resilient urban green spaces begins with legal and policy reform. The city’s existing regulatory framework represents a good foundation, but several noticeable gaps remain in the scope of green infrastructure requirements, in the equity of their application, and in the procedural and restorative justice commitments that must accompany any genuine green space investment strategy.

The GBO represents Denver’s most significant green infrastructure mandate, but its current threshold excludes a substantial share of the city’s-built environment. Because the GBO applies only to commercial and mixed-use developments exceeding 25,000 sq. ft., smaller residential and commercial projects, such as the Mariposa District, fall entirely outside its reach.^[281] Lowering the GBO threshold to 10,000 sq. ft. or less would extend green infrastructure requirements to a broader range of development project, and therefore make a big difference to Denver’s urban greening initiatives.^[282] The city should also add incentives for retrofitting older buildings with green roofs or other green features. Even if Denver resorts to tax breaks, grants, or fast-track permitting, just providing incentives for developers to get on board with these urban greening initiatives would be a huge leap forward to mobilize green infrastructure investment in the existing building stock rather than limiting reform to new construction.

The GBO was not designed to reach residential neighborhoods, however, and lowering the commercial threshold alone will not close that gap. Denver should consider a complementary residential green infrastructure policy that extends green incentives to single-family and multi-family residential development. The current policy leaves this building typology entirely unaddressed.^[283]

Equity must be a core organizing principle of Denver’s legal and policy reforms, not an afterthought. Referring to the Tree Equity Scores in Denver, some neighborhoods are doing well, with great access to green spaces, while others have lower scores. That is not just unjust to these communities, it’s also unsustainable. Adopting a Tree Equity mandate, modeled on the equity targeting goals of Chicago’s CRTI, could help level the playing field and provide equitable access to these spaces so everyone can enjoy the benefits of them. Accessibility must also be mandated rather than aspirational. The ten-minute walk standard described in Denver’s Game Plan for a Healthy City should be codified as a planning requirement, not merely a design goal. This would ensure that all residents have guaranteed proximity to quality green space regardless of neighborhood income level. Denver could take inspiration from Philadelphia’s Pollinator Gardens, which turned vacant lots into vibrant green spaces. Denver can do the same in its underserved neighborhoods, where vacant and underutilized land represents an untapped opportunity for equitable green space expansion.

Community engagement is not merely a best practice—it is procedural justice. Scholarly work on climate and environmental justice identifies procedural justice as “ensuring that those affected by the decisions can participate meaningfully in the decision-making process.”^[284] Genuine procedural justice in green space development requires more than public comment periods; it demands that residents of communities like the Mariposa District have substantive influence over project design, species selection, and maintenance priorities from the outset of the planning process rather than as an afterthought. Equity in green space investment also requires attention to restorative justice. Anti-displacement protections must accompany green investment in vulnerable communities to ensure that environmental improvement does not produce social displacement, and that communities bearing historical environmental burdens are able to remain and benefit from those improvements.^[285]

B. Funding Mechanisms

Securing adequate and equitable funding is essential to translating Denver’s green space policy commitments into practice. Funding is usually a sticking point, but there are tactical ways to address this challenge. Houston’s Bayou at Midtown Park demonstrated that collaboration between the city, private developers, and community groups can produce significant green infrastructure outcomes that neither sector could achieve independently. Public-private partnerships of this kind carry displacement risks, however, and Denver should structure any public-private green space initiative to include community benefits agreements that bind participating developers to affordable housing contributions and anti-displacement protections as conditions of participation.^[286] Denver can further incentivize private green infrastructure investment through expedited permitting, for developers who implement qualifying green space into their developments.^[287]

Denver should also direct attention to underutilized public land as an equity-centered funding strategy. Schoolyards, surface parking lots, and other publicly owned parcels represent untapped capacity for green space expansion without land acquisition costs that constrain new park development. Paired with state and federal grants, these incentive and collaborative funding efforts would comprise a workable funding strategy.

C. Implementation and community engagement

Translating Denver’s legal and funding commitments into durable green space outcomes requires a strategic and integrated approach to implementation. The city’s case study comparators offer instructive models, but also cautionary lessons that Denver’s planners should take seriously.

Integrating green infrastructure with stormwater management, as Houston has done, can address flooding and water quality issues while boosting urban resilience. A systems-thinking approach, like Chicago’s CRTI, treats parks and green spaces as components of a connected regional network, rather than isolated patches of green space. That entails creating green corridors that link parks, trails, and natural areas, improving biodiversity, and making the city more walkable simultaneously. Chicago’s experience offers a cautionary lesson as well—the canopy decline from twenty percent to eighteen percent between 2010 and 2020 that motivated CRTI’s creation, including the loss of thirteen million trees to a single invasive species, illustrates the consequences of reactive rather than proactive urban forestry policy.^[288] Denver’s persistently low Tree Equity Scores in neighborhoods like the Mariposa District signal an emerging deficit that demands investment now, before the city confronts a comparable crisis.

Houston’s Bayou at Midtown Park further shows how green infrastructure can be intertwined with urban design, blending functionality with beauty. Denver could learn from this by using green spaces to tackle multiple goals such as managing stormwater, cooling the city, and creating community gathering spots, simultaneously.

The workforce is another key element of green space growth. Green spaces do not maintain themselves, and without a skilled workforce these urban green spaces could very well deteriorate. Denver has an opportunity to build a green workforce from the ground up, creating jobs in urban forestry, green infrastructure development, and park maintenance. Additionally, Denver could advertise in local high schools and universities that they provide apprenticeships and training programs, which then would create opportunities for these individuals to gain skills in this field. By investing in workforce development, Denver would not just be maintaining its urban green spaces, but it would also be empowering its residents, fostering economic opportunities through the creation of jobs, and creating long-term sustainability of its urban greening initiatives.

Long-term sustainability also requires designing green spaces to withstand the compounding pressure of climate change. Denver’s green infrastructure should incorporate drought-resistant native species, shaded areas, and water-efficient irrigation systems capable of performing under the extreme heat, drought, and heavy rainfall events that climate models project will intensify across the Colorado Front Range.^[289] Additionally, to monitor and evaluate the effectiveness of these designs, Denver could utilize tools like the Tree Equity Score and i-Tree Eco Model to track progress and make sure these green spaces are up to par.

VII. Future Research Directions

Future research should focus on evaluating the effectiveness of urban greening strategies, specifically assessing the long-term environmental, social, and economic benefits of green space investments. Studies could explore the quantifiable impacts of green spaces on urban heat island mitigation, air quality, and public health, providing data to support further policy development.

Additionally, there is significant potential for adapting successful urban greening models from one region to another. Research on the transferability of green space initiatives, particularly in cities with different demographic, economic, and geographic characteristics, could help tailor solutions to local contexts. Furthermore, examining how public lands can be leveraged for urban greening, offers another promising avenue for future study. Public lands have untapped potential to support green infrastructure development, and further exploration of their role could provide valuable insights for urban planners and policymakers seeking sustainable solutions for green space expansion.

Future research should also examine the recognitional dimension of environmental justice in Denver’s green space planning context. Recognitional justice asks whether the structural vulnerabilities and intersecting identities of affected communities are genuinely centered in environmental decision-making.^[290] This is done not merely by consultation in a procedural sense but substantive incorporation into planning priorities and outcomes.^[291] Denver has taken steps toward community engagement in its climate and green space initiatives, including Rapid Assessments in underserved neighborhoods, community-based tree planting partnerships, and outreach through the Promotoras Climacticas program.^[292] Whether these efforts satisfy the deeper demands of recognitional justice is a question this Note’s quantitative methodology is not equipped to answer, and one that warrants dedicated qualitative and community-based research.

VIII. Conclusion

Urban green spaces are not merely aesthetic to an urban landscape, they are infrastructure. They cool cities, filter air, absorb stormwater, support biodiversity, promote public health, and generate economic value. But as this Note has documented, those benefits are not reaching all of Denver’s communities equally. The city’s most ambitious green infrastructure investment has been concentrated in commercial corridors and affluent neighborhoods, while the communities that bear the greatest environmental burdens and have the least capacity to absorb them—record the city’s lowest Tree Equity Scores and received the least benefit from the regulatory frameworks designed to advance urban sustainability.

This Note has argued that Denver’s green space policies, while meaningful in scope, fall short of the just green enough standard the Note’s framework demands. The GBO’s 25,000 sq. ft. threshold creates a structural exclusion that leaves neighborhoods like the Mariposa District entirely outside the ordinance’s reach—communities where documented environmental justice concerns, brownfield histories, and persistent canopy deficits make green infrastructure most urgent. The Tree Equity Score data confirms what the policy analysis suggests: Denver’s composite scores mask severe localized disparities, and the gap between the city’s aggregate performance and its worst-served neighborhoods has not narrowed despite significant investment. Most paradoxically, the green gentrification dynamic documented in Section V suggests that investment without deliberate anti-displacement protections can actively worsen the inequities it claims to address, pricing out the very communities the investment was meant to benefit.

The recommendations this Note advances respond directly to these findings. Expanding the GBO threshold, adopting a complementary residential green infrastructure policy, codifying a Tree Equity mandate, and requiring community benefits agreements as conditions of public-private green space partnerships would begin to close the gap between Denver’s ecological ambitions and its equity commitments. These reforms are not sufficient on their own, they must be accompanied by genuine procedural justice in the planning process, ensuring communities have substantive influence over the design and implementation of green infrastructure in their neighborhoods rather than being treated as passive recipients of decisions made elsewhere. And they made anti-displacement protections robust enough to ensure that environmental improvement does not become another mechanism of displacement in a city that has already experienced some of the most intense gentrification pressure in the American West.

The Mariposa District is Denver’s test case. It is a community with a documented brownfield history, an EPA environmental justice designation, a Tree Equity Score of 62, a nationally recognized cultural heritage of the Chicano movement, and active displacement pressure from rising housing costs—all in a neighborhood that has already received significant green infrastructure investment without that investment translating into equitable outcomes. Whether Denver can close the gap between investment and equity in the Mariposa District will determine whether the city’s green space policies are achieving justice or merely achieving greenness. The two are not the same thing, and this Note has been an argument for treating that difference as the central challenge of urban green space policy in Denver and beyond.

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GOVERNOR’S OFF. OF CLIMATE PREPAREDNESS & DISASTER RECOVERY, COLORADO CLIMATE PREPAREDNESS ROADMAP2023). ↑
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Denver’s Green Buildings Ordinance, Denver the Mile High City, https://www.denvergov.org/Government/Agencies-Departments-Offices/Agencies-Departments-Offices-Directory/Community-Planning-and-Development/Plan-Review-Permits-and-Inspections/Commercial-and-Multifamily-Projects/Green-Buildings-Ordinance (last visited Feb. 17, 2025). (requiring developers and property owners to select from sustainable development strategies aimed at increasing green space, improving stormwater management, promoting renewable energy, and advancing the city’s climate action and resilience goals); Denv. Parks & Recreation Game Plan for a Healthy City: Final Report (2019) (providing a strategic roadmap guiding the development of new policies and regulations to protect and expand parks, and describing parks, recreation, and the urban forest as vital green infrastructure contributing to the city’s environmental resilience and climate adaptation); Division of Green Infrastructure, Denver the Mile High City, https://www.denvergov.org/Government/Agencies-Departments-Offices/Agencies-Departments-Offices-Directory/Department-of-Transportation-and-Infrastructure/Programs-Services/Green-Infrastructure#:~:text=The%20City%20and%20County%20of,stormwater%20runoff%20from%20city%20streets. (describing Denver’s effort to make green infrastructure a fundamental part of the city’s long-term strategy, with benefits including urban heat island mitigation, reduced flooding risks, climate change resiliency, and enhanced community livability). ↑
Alessandro Rigolon, Parks and Younger People: An Environmental Justice Study of Park Proximity, Acreage, and Quality in Denver, Colorado, LANDSCAPE & URB. PLAN., Sept. 2017, at 73. ↑
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Sirkku Juhola et al., Connecting Climate Justice and Adaptation Planning: An Adaptation Justice Index, 136 Envtl. Sci. & Pol’y 609, 610–11 (2022); see also Sonia Brondi, Giacomo Chiara & Elisa Matutini, Navigating Environmental Justice Framework: A Scoping Literature Review Over Four Decades, 18 Envtl. Just. 3 (2025); Robert D. Bullard, Environmental Justice in the 21st Century, Envtl. Just. Res, Ctr. (2000), https://www.uwosh.edu/sirt/wp-content/uploads/sites/86/2017/08/Bullard_Environmental-Justice-in-the-21st-Century.pdf,. ↑
See infra Section VI. ↑
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Id. (quoting Suetonius, The Lives of the Caesars: Nero 31). ↑
Id. (quoting Tacitus). ↑
Chkird et al., supra note 19, at 4. ↑
Alan Tate, Urban Parks in the Twentieth Century, 24 Env’t & Hist. 81, 82 (2018); Ann E. Chapman, Nineteenth Century Trends in American Conservation, Nat’l Park Serv., https://www.nps.gov/articles/19th-century-conservation.htm (last visited Apr. 30, 2026); Rozalija Cvejić et al., A Typology of Urban Green Spaces, Ecosystem Services Provisioning Services and Demands 8 (GREEN SURGE Project Rep. D3.1, 2015), https://assets.centralparknyc.org/pdfs/institute/p2pupelp/1.004_Greensurge_A+Typology+of+Urban+Green+Spaces.pdf. ↑
Chapman, supra note 26; Yang Xing & Peter Brimblecombe, Trees and Parks as “The Lungs of Cities”, 48 Urb. Forestry & Urb. Greening 126552, at 2 (2020), https://www.sciencedirect.com/science/article/pii/S1618866719304765. ↑
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Id. (noting that New York’s Central Park inspired connected park systems in cities such as Chicago, Buffalo, and Minneapolis). ↑
C.N.E. Corbin, The Rise of Green Spaces in Inner Cities, Afr. Am. Intell. Hist. Soc’y (Nov. 29, 2017), https://www.aaihs.org/the-rise-of-green-spaces-in-inner-cities/. ↑
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Yuanqiu Feng & Puay Yok Tan, Imperatives for Greening Cities: A Historical Perspective, in Greening Cities: Forms and Functions 41, 42 (Puay Yok Tan & C. Y. Jim eds., 2017).; Hanneke Kruize et al., Urban Green Space: Creating a Triple Win for Environmental Sustainability, Health, and Health Equity through Behavior Change, 16 Int’l J. Env’t Rsch. and Pub. Health 4403, 7 (2019). ↑
History Colo., Denver Park and Parkway System Thematic Resource, Nat’l Register of Historic Places (accepted 1986), https://www.historycolorado.org/national-state-register/denver-park-and-parkway-system (identifying landscape architects including Reinhard Schuetze, George E. Kessler, the Olmsted Brothers, and Saco R. DeBoer as principal designers of the Denver park and parkway system); see also History Colo., Denver Mountain Parks, Nat’l Register of Historic Places (accepted 1990), https://www.historycolorado.org/national-state-register/denver-mountain-parks (noting the system reflects the City Beautiful Movement among other national planning movements of the twentieth century); Nat’l Park Serv., Denver Parks, Frederick Law Olmsted Nat’l Historic Site, https://www.nps.gov/places/denver-parks.htm (last visited Apr. 30, 2026) (describing Frederick Law Olmsted Jr.’s commission, accepted in 1911, to plan a chain of parks and interconnecting roadways for the Denver region, with his first report delivered in 1912). ↑
See 42 U.S.C. § 9601(39)(A) (2018) (defining “brownfield site” as “real property, the expansion, redevelopment, or reuse of which may be complicated by the presence or potential presence of a hazardous substance, pollutant, or contaminant”); U.S. EPA Office of Brownfields and Land Revitalization, The Mariposa-Lincoln Park Public Housing Redevelopment 21 (2012) (describing EPA-funded brownfields environmental assessment and cleanup grant to the City and County of Denver prior to redevelopment). ↑
U.S. EPA Office of Brownfields and Land Revitalization, supra note 43, at 21 (characterizing the Mariposa District as “a community with environmental justice concerns” and describing the site’s acquisition by the Denver Housing Authority for transformation into mixed-use, transit oriented development with affordable housing). ↑
Id. at 21-22 (noting the redevelopment included LEED Platinum construction, low-impact stormwater management infrastructure incorporated into the city’s Master Development Plan, 123 community meetings and group interviews convened with a range of stakeholders including residents, community leaders, city agencies, and local government representatives). ↑
American Forests, Tree Equity Score, https://www.treeequityscore.org/map (last visited Mar. 7, 2025); see infra Figure 1 (noting that Tree Equity Scores reflect data as of March 7 2025, and that the adjacent Sun Valley neighborhood records a lower score than the Mariposa District as of the date of publication); see also infra Section IV.C.a. (analyzing Tree Equity Score disparities across Denver and surrounding municipalities). ↑
Corinne Neustadter, The Colorado River Compact and the Future of Green Spaces, CSU Source (July 26, 2022), https://source.colostate.edu/the-colorado-river-compact-and-the-future-of-green-spaces/ (quoting Lori Catalano, Professor of Landscape Architecture, Colorado State University, noting that green space design traditions “migrated from a humid climate in the East to the semi-arid climate in the West,” and reporting that CSU researchers found most streams in the Denver parks system exist only because of sprinkler runoff). ↑
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Sarah DeWeerdt, Green infrastructure can set off a virtuous cycle of climate action, Anthropocene Mag. (Sep. 12, 2023), https://www.anthropocenemagazine.org/2023/09/green-infrastructure-can-set-off-virtuous-cycle-of-climate-action/; see also Jiahua Yu et al., The Impact of Street Greenery on Active Travel: A Narrative Systematic Review, 12 Frontiers In Pub. Health 1337804 (2024) (reviewing twenty-six cross-sectional studies and finding that street greenery generally promotes walking and cycling by enhancing comfort through shade and cooler temperatures, improving environmental aesthetics, and fostering social interactions, with the majority of included studies reporting a positive association between street greenery and active travel behaviors). ↑
DeWeerdt, supra note 57. ↑
Caragh G. Threlfall et al., Increasing Biodiversity in Urban Green Spaces Through Simple Vegetation Interventions, 54 J. Applied Ecology 1874 (2017). ↑
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Benefits of Trees and Vegetation, EPA, https://www.epa.gov/heatislands/benefits-trees-and-vegetation (last visited April 21, 2026) (explaining that urban trees support stormwater management in three ways: absorbing excess rainfall to reduce runoff, filtering pollutants from paved surfaces during storms, and providing shade to cool water runoff, with urban tress absorbing between 15 to 27% of annual rainfall); see also Kruize et al., supra note 41 (noting that green space may help reduce flooding risk by increasing water retention and reducing runoff). https://pmc.ncbi.nlm.nih.gov/articles/PMC6888177/ ↑
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How Parks and Green Spaces Can Improve Your Health, N.C. State Univ., Coll. of Nat. Res. (Apr. 20, 2022), https://cnr.ncsu.edu/news/2022/04/parks-green-spaces-improve-health/. ↑
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Viniece Jennings & Omashalewa Bamkole, The Relationship between Social Cohesion and Urban Green Space: An Avenue for Health Promotion, 16 Int’l J. Env’t Rsch. and Pub. Health, 452 (2019). ↑
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The Trust for Public Land, The Economic Benefits of Denver’s Park and Recreation System 1, 4 (2010). ↑
Id. ↑
See id. at 3. (noting that the study encompassed 47.085 residential properties of varying types within 500 feet of parks across Denver, suggesting the park proximity premium extends broadly across the city’s residential market rather than being confined to high-value properties). ↑
Lee Hill, Urban Green Spaces: Sustainability Benefits and Challenges, GREENER INSIGHTS, https://greenerinsights.com/urban-green-spaces-sustainability-benefits-challenges/ (last visited Feb. 17, 2025). ↑
The Trust for Public Land, The Economic Benefits of Denver’s Park and Recreation System 1, 5-6 (2010) (finding that Denver’s park system directly drives tourism, with an estimated 711, 376 visitors citing parks as a primary reason for visiting Denver in 2008, generating over $3 million in city tax revenue and $18 million in collective citizen wealth from park-based tourism, and noting that travel publications consistently highlight Denver’s parks and outdoor amenities as key attractions); see also Zoe Harper, Denver Real Estate Market Overview – 2025, STEADILY BLOG, https://www.steadily.com/blog/denver-real-estate-market (last visited Feb. 17, 2025). ↑
Tourism Pays for Denver, VISIT DENVER, https://www.denver.org/tourism-pays/tourism-pays-for-denver/ (last visited Feb. 17, 2025). ↑
Economic Benefits of Green Infrastructure, EPA, https://www.epa.gov/green-infrastructure/economic-benefits-green-infrastructure (last visited Feb. 17, 2025). ↑
Id. ↑
Id. ↑
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Sue Rochman, Neighborhood Green Space tied to lower health care costs, KAISER PERMANENTE DIV. of RSCH. (March 8, 2022), https://divisionofresearch.kaiserpermanente.org/green-space-health-care-costs/. ↑
S. Van Den Eeden et al., Association Between Residential Green Cover and Direct Healthcare Costs in Northern California: An Individual Level Analysis of 5 Million Persons,163 Env’t Int’l, Mar. 2022, at 1, 4. ↑
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Emily G. Bergeron, A Right to Nature: Addressing Disparities in Green Space Access, A.B.A. (Oct. 30, 2024), https://www.americanbar.org/groups/crsj/resources/human-rights/2024-october/right-to-nature/. ↑
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Downtown Denver, Wikipedia, https://en.wikipedia.org/wiki/Downtown_Denver (last visited Jan. 11, 2026) (noting downtown Denver contains over 23 million sq. ft. of office space with 132,000 workers); See also Denver, CO Commercial Real Estate for Lease and Sale, PropertyShark, https://www.propertyshark.com/cre/commercial-real-estate/us/co/denver/ (last visited Jan. 11, 2026) (identifying LoDo neighborhood as having one of the highest concentrations of commercial property listings in Denver). ↑
See infra Section IV.B.1 (noting that Tree Equity Scores reflect data as of March 7,2025 and that the adjacent Sun Valley neighborhood records a lower score than the Mariposa District as of the date of publication). ↑
Mariposa, Denver Hous. Auth., https://www.denverhousing.org/mariposa/ (last updated Mar. 4, 2024) (describing mixed-income redevelopment with Phase 2 containing 5,500 sq. ft. and Phase 3 containing 11,000 square feet of commercial space); Erin Douglas, Denver’s Mariposa District Leads Charge in Changing the Face of Public Housing, Denver Post (Aug. 4, 2017), https://www.denverpost.com/2017/08/04/mariposa-district-denver-public-housing/ (characterizing Mariposa residents as “mostly Hispanic, mostly women, and mostly low-income”); see also Kate Siber, How a Vital Denver Neighborhood is Maintaining Its Cultural History, Preservation Mag. (Winter 2022), https://savingplaces.org/stories/how-a-vital-denver-neighborhood-is-maintaining-its-cultural-history (documenting the La Alma Park neighborhood’s five-year grassroots preservation effort and noting ongoing gentrification pressures including rising home prices and displacement of longtime residents, community leaders, and activists). ↑
See infra Section IV.B.1 (analyzing Tree Equity Scores and i-Tree data showing Mariposa District’s limited tree canopy and associated environmental burdens). ↑
Denv. Parks & Recreation, Design Standards for Urban Parks and Natural Open Space: Urban Parks and Natural Open Space (2004). ↑
Denv. Parks &Recreation, Planning, Design + Construction Standards 1-1 (2018) (“The DPR Standards document is a tool designed to complement the Game Plan by organizing design, planning and construction efforts while Denver transforms into a City in a Park.”). ↑
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Denv. Parks & Recreation, supra note 109, (detailing DPR’s responsibilities for managing, operating, and controlling all park facilities). ↑
Id. at 3-1–3-37 (establishing design and development standards including grading requirements, park infrastructure specifications, utility depths, landscape requirements, and accessibility features). ↑
Parks & Recreation, Denv. The Mile High City, https://www.denvergov.org/Government/Agencies-Departments-Offices/Agencies-Departments-Offices-Directory/Parks-Recreation (last visited Jan. 11, 2026) (noting DPR maintains 250+ urban parks, 20,000 acres of urban and mountain parkland, and 30 recreation centers). ↑
City & Cnty. of Denver, Rules and Regulations for General Development Plans (2005) (establishing Development Review Committee consisting of managers from Community Planning and Development, Public Works, and Parks and Recreation, which reviews all General Development Plans to ensure compliance with city standards, including park dedications). ↑
Denv. Parks & Recreation , supra note 109, at 1-3 (describing DPR community partnerships and role in guiding private development contributions to parks system). ↑
City & Cnty. of Denver, supra note 115, at 1-1 (“Public amenities such as streets, sidewalks and tree lawns, parkways, parks, creek corridors, open spaces and direct access to permanent mass transit facilities should be used to organize private development.”) (citing Denver Revised Municipal Code § 59-301(a)). ↑
Denv. Parks & Recreation, supra note 109, at 12, 14. ↑
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Denv. Parks & Recreation Game Plan for a Healthy City: Final Report (2019). ↑
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Colo. Rev. Stat. § 24-32-3708 (2024). ↑
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See Tree Equity Score: Methods & Data, Am. Forests, https://www.treeequityscore.org/methodology; see also infra Figure 1 (noting that Tree Equity Scores reflect data as of March 7, 2025 and that Denver’s Mariposa District recorded a score of sixty-two at the time of research). ↑
i-TREE TOOLS, i-Tree Eco Overview, https://www.itreetools.org/tools/i-tree-eco/i-tree-eco-overview (last visited Feb. 17, 2025). ↑
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See Tree Equity Score Map, Am. Forests, https://www.treeequityscore.org/map (last visited Mar. 7, 2025). All scores reflect data as of March 7, 2025. At the time of research, the Mariposa District recorded Denver’s lowest neighborhood Tree Equity Score of sixty-two. As of publication, the adjacent Sun Valley neighborhood records a lower score of sixty. Composite scores are not materially affected by individual score updates. Scores for all cities may have changed since date of research. ↑
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See Ishan Thakore, Suncor Repeatedly Broke Federal Air Pollution Rules at Commerce City Refinery, Environmental Groups Allege in New Lawsuit, CPR News (Aug. 6, 2024, 5:58 PM), https://www.cpr.org/2024/08/06/lawsuit-alleges-suncor-energy-repeatedly-broke-federal-air-pollution-rules-commerce-city/; see also Federal, State Inspections Indicate Suncor Refinery Violated Air Quality Regulations, Colo. Dep’t of Pub. Health & Env’t, https://cdphe.colorado.gov/press-release/federal-state-inspections-indicate-suncor-refinery-violated-air-quality-regulations (last visited July 19, 2025). ↑
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2022 ASLA Professional Awards, Midtown Park, Am. Soc’y of Landscape Architects, https://www.asla.org/2022awards/5424.html (last visited Feb. 17, 2025). ↑
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Houston’s Midtown Park Wins Numerous Design Awards for Sustainable Green Space, DeepRoot, https://www.deeproot.com/case-studies/silva-cell/houstons-midtown-park-wins-numerous-design-awards-for-sustainable-green-space/ (last visited Feb. 17, 2025). ↑
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Chicago Region Trees Initiative, Morton Arboretum, https://mortonarb.org/plant-and-protect/chicago-region-trees-initiative/ (last visited Feb. 17, 2025). ↑
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U.S. Climate Data, Climate Houston – Texas, https://www.usclimatedata.com/climate/houston/texas/united-states/ustx0617 (last visited Jan. 11, 2026) (noting Houston receives average annual precipitation of 45 inches); U.S. Climate Data, Climate Denver – Colorado, https://www.usclimatedata.com/climate/denver/colorado/united-states/usco0105 (last visited Jan. 11, 2026) (noting Denver receives average annual precipitation of 15 inches); see also Denv. Parks & Recreation, supra note 120, at 34–35 (identifying drought as increasing risk and noting irrigation costs account for 11% of DPR’s operating budget). ↑
See Denv. Parks and Recreation, supra note 109; see also supra Section IV.B.2.a (discussing Bayou at Midtown Park’s use of bioswales and rain gardens for stormwater management). ↑
Community Health & the Environment in Commerce City-North Denver, Colo. Env’t Pub. Health Tracking, https://coepht.colorado.gov/ccnd (last visited March 7, 2025) (reporting respiratory health data for Commerce City); see also infra Fig, 2 (compiling i-Tree data showing Commerce City uses merely 1.4 percent of its plantable space). ↑
Forest Rsch., Development Pressure – Challenges and Practical Considerations, https://www.forestresearch.gov.uk/tools-and-resources/fthr/urban-regeneration-and-greenspace-partnership/practical-considerations-and-challenges-to-greenspace/ (last visited Feb. 17, 2025). ↑
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Madeline Craig-Scheckman et al., What You Don’t Know Can’t Help You: Public awareness about social and green infrastructure, 114 Int’l J. Disaster Risk Reduction 104891 (2024). ↑
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Karlen Beitman, How Does Soil Contamination Affect Real Estate?, LandApp, https://www.landapp.com/post/how-does-soil-contamination-affect-real-estate (last updated Nov. 27, 2024). ↑
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Deeprooot, supra note 175 (describing the use of 594 Silva Cells at Midtown Park to provide adequate soil volume for twenty-one trees planted above an underground parking garage while supporting pedestrian hardscapes). ↑
How to Develop an Effective Contaminated Soil Management Plan, Desert Env’t, https://www.desertenv.com/how-to-develop-an-effective-contaminated-soil-management-plan (last visited Feb. 17, 2025). ↑
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Sara Khoshkar et al., Opportunities and Challenges for the Integration of Green Qualities in the Densification of Regional Cores of Stockholm, Int’l Assoc. for Impact Assessment (Apr. 2015) https://conferences.iaia.org/2015/Final-Papers/Khoshkar,%20Sara%20-%20Opportunities%20and%20Challenges%20for%20the%20Integration%20of%20Green%20Qualities%20in%20the%20Densification%20of%20Regional%20Cores%20of%20Stockholm.pdf. ↑
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Alicia Biasotti, The Challenges of Urban Green Spaces and How They Might Be Resolved, ACB Consult. Servs. LLC, https://www.acbconsultingservices.com/sustainable-construction-project-management/the-challenges-of-urban-green-spaces-and-how-they-might-be-resolved/ (last visited Feb. 3, 2025). ↑
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Ingenthron, supra note 78; see also 80Well-Maintained Landscaping Hasa Positive Impact on Property Values, Project Evergreen, https://projectevergreen.org/well-maintained-landscaping/ (last visited Feb. 17, 2025).. ↑
Wolch et al., supra note 2; Sarah Dooling, Ecological Gentrification: A Research Agenda Exploring Justice in the City, 33 Int’l J. Urb. & Regional Res. 621, 621 (2009); Melissa Checker, Wiped Out by the ‘Greenwave’: Environmental Gentrification and the Paradoxical Politics of Urban Sustainability, 23 City & Soc’y 210, 210 (2011). ↑
Maggie McNulty, Desire in a Damaged Landscape: The Promise and Paradox of Denver’s Platte Farm Open Space, Envtl. Hist. Now (Apr. 23, 2026), https://www.environmentalhistorynow.org/desire-in-a-damaged-landscape/ (discussing the relationship between environmental remediation and property value rebounds in urban environmental justice communities, citing Jeremy Bryson, The Nature of Gentrification, 7 Geography Compass 578 (2013); Hamil Pearsall & Isabella Anguelovski, Contesting and Resisting Environmental Gentrification, 21 Socio. Rsch. Online 121 (2016)). ↑
See id. ↑
Karen Chapple, Timothy Thomas & Miriam Zuk, Denver — Gentrification and Displacement, Urb. Displacement Project (2021), https://www.urbandisplacement.org/maps/denver-gentrification-and-displacement/ (finding that sixty-one percent of Denver neighborhoods experienced rapid housing cost increases between 200 and 2017, that more than fifty thousand low-income Denver households live in neighborhoods at risk of or experiencing gentrification and displacement risk is concentrated in Denver’s communities of color, particularly Hispanic and Black households being displaced to areas with poorer access to transit and services); see also McNulty, supra note 266 (reporting that Denver ranked among the most intensely gentrifying cities in the United States between 2013 and 2017). ↑
Id. ↑
U.S. EPA Office of Brownfields and Land Revitalization, The Mariposa-Lincoln Park Public Housing Redevelopment 21–22 (2012); Siber, supra note 107. ↑
See generally Wolch et al., supra note 2. ↑
Justin Dorazio, Localized Anti-Displacement Policies: Ways to Combat the Effects of Gentrification and Lack of Affordable Housing, Ctr. for Am. Progress (Sept. 26, 2022), https://www.americanprogress.org/article/localized-anti-displacement-policies/. ↑
Joe Kriesberg, Strategies for Responding to Gentrification, Joint Ctr. for Hous. Stud. (June 4, 2018), https://www.jchs.harvard.edu/blog/strategies-for-responding-to-gentrification (observing that inclusionary units may not prevent displacement of existing residents because new tenants may come from outside the neighborhood, and that focusing solely on affordability percentages fails to address the underlying dynamics of neighborhood change); Dorazio supra note 272 (concluding that no single anti-displacement policy is sufficient on its own). ↑
Dorazio supra note 272; Jeremy Németh, Four Steps to Stopping Gentrification, CU Denv. News (Aug. 29, 2019), https://news.cudenver.edu/four-steps-to-stopping-gentrification/. ↑
Kriesberg, supra note 273; see also Siber, supra note 107. ↑
Biasotti, supra note 259. ↑
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See Biasotti, supra note 259. ↑
See supra Section III.A (analyzing the GBO’s 25,000 sq. ft. threshold and its failure to reach smaller residential developments). ↑
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Juhola et al., supra note 14. ↑
See supra Section V (discussing anti-displacement strategies as a component of equitable green infrastructure investment); see also Juhola et al., supra note 14. ↑
Wolch et al., supra note 2 (warning that green space investment without anti-displacement measures risks perpetuating environmental injustice by displacing low-income residents and communities of color); see also McNulty, supra note 266; Dorazio, supra note 272. ↑
Dorazio, supra note 272. ↑
See supra Section IV.C. ↑
See supra Section II.A (describing Denver’s semi-arid climate and tension between the city’s historic green landscape aesthetic and the region’s natural water constraints, a tension that will intensify as climate change tightens pressure on the Colorado River Basin). ↑
Juhola et al., supra note 14 (defining recognitional justice as “the acknowledgement of plurality of societal actors, and their differing needs, desires, and abilities,” including recognition of community members’ intersecting identities and structural vulnerabilities.) ↑
Environmental Justice, Off. of Climate Action, Sustainability & Resiliency, City & Cnty. of Denver https://www.denvergov.org/Government/Agencies-Departments-Offices/Agencies-Departments-Offices-Directory/Climate-Action-Sustainability-and-Resiliency/Cutting-Denvers-Carbon-Pollution/Environmental-Justice (last visited May 1, 2026); Community Climate Needs Assessment, Off. of Climate Action, Sustainability & Resiliency, City & Cnty. of Denver https://www.denvergov.org/Government/Agencies-Departments-Offices/Agencies-Departments-Offices-Directory/Climate-Action-Sustainability-and-Resiliency/Cutting-Denvers-Carbon-Pollution/Environmental-Justice/Community-Climate-Needs-Assessment (last visited May 1, 2026); Equitable Community Tree Planting Initiative, Off. of Climate Action, Sustainability & Resiliency, City & Cnty. of Denver https://www.denvergov.org/Government/Agencies-Departments-Offices/Agencies-Departments-Offices-Directory/Climate-Action-Sustainability-and-Resiliency/Cutting-Denvers-Carbon-Pollution/Climate-Adaptation-and-Resiliency/Equitable-Community-Tree-Planting-Initiative (last visited May 1, 2026); Promotoras Climacticas, Off. of Climate Action, Sustainability & Resiliency, City & Cnty. of Denver https://www.denvergov.org/Government/Agencies-Departments-Offices/Agencies-Departments-Offices-Directory/Climate-Action-Sustainability-and-Resiliency/Cutting-Denvers-Carbon-Pollution/Community-Engagement/Promotoras-Climacticas (last visited May 1, 2026). ↑
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