Last updated: November 2024
Minimizing heat stress is a critical priority for Phoenix, the hottest major city in the U.S., where heat-related deaths reached at least 359 across Maricopa County last year. The city's expansive urban layout and infrastructure exacerbate the urban heat island effect, making an already scorching climate even more hazardous. In addition, heat impacts communities unequally, with some neighborhoods up to 10 degrees hotter than others. Lower-income and predominantly Hispanic neighborhoods often have less canopy cover and fewer resources to combat rising temperatures, making them more vulnerable to extreme heat. To address this, the City of Phoenix launched the Cool Corridors Program in 2020, a key initiative in its broader climate resilience strategy. This program, a partnership with American Forests and the Phoenix Street Transportation Department, aims to establish a network of shaded pathways that connect communities across the city. These corridors enable residents to travel safely to schools, public transit, and other city hubs, promoting environmental sustainability and public health. The program prioritizes investment in low-income, heat-sensitive neighborhoods to improve tree equity and create green spaces where they’re most needed. The first Cool Corridor was developed in 2022 at Cesar Chavez Park, where over 250 trees were planted with the support of more than 100 volunteers, setting a strong example for future initiatives. By 2030, Phoenix plans to complete 100 Cool Corridors citywide, building a more resilient and livable urban environment for all residents. (1-5, 7-8, 10)
Volunteers and corporate and nonprofit partners helped Phoenix plant 259 trees along its first "cool corridor," along Baseline Road at Cesar Chavez Park.
Brandon Loomis/The Republic
Overview
Nature-based solution
- Grey infrastructure featuring greens
- Alley or street trees and other street vegetation
- Parks and urban forests
- Pocket parks/neighbourhood green spaces
Key challenges
- Climate action for adaptation, resilience and mitigation (SDG 13)
- Climate change adaptation
- Green space, habitats and biodiversity (SDG 15)
- Green space creation and/or management
- Health and well-being (SDG 3)
- Improving physical health
- Social justice, cohesion and equity (SDG 10)
- Social justice and equity
- Environmental and climate justice
- Sense of community and community engagement
Principal problems in Functional Urban Area (FUA)
- Climate-Related Hazards
- Heat stress & Extreme temperatures
- Health, Well-being and Social cohesion
- Physical health harm (from pollution, wildfire, extreme temperature)
Key priorities
Climate action (adaptation and/or mitigation), Social Justice and community
Focus
Creation of new green areas, Creation of green corridors (including connectivity between urban and rural ecosystems), Creation of any other green urban spaces, Strategy, plan or policy development, Creation of city-wide or neighborhood climate adaptation or mitigation strategies/programs
Project objectives
The goals of the tree planting at Cesar Chavez Park as part of the Cool Corridors Program were to:
To support the city’s goal of establishing 100 Cool Corridors by 2030.
To create a network of shaded, environmentally-friendly corridors across communities, encouraging safe movement from residential areas to key city locations.
To plant trees that offer relief from extreme heat and promote Tree Equity, ensuring all residents, regardless of race or income, have access to the life-saving benefits of tree cover.
To prioritize planting locations that serve students walking to and from schools, public transit users, and community residents.
To involve the local community in project activities and promote community engagement (1, 11)
Implementation activities
To achieve the goals, the City of Phoenix engaged in various activities including:
The City of Phoenix has taken significant steps toward enhancing urban shade and promoting Tree Equity through a multi-faceted approach. First, Phoenix became the first U.S. city to pledge Tree Equity by establishing a five-year partnership with American Forests (1). This partnership supports the city's goals through collaboration with the Street Transportation Department, which helps secure funding and facilitates implementation efforts (1, 8). In 2021, a budget of $1.5 million was approved for the Cool Corridors program, emphasizing Phoenix’s commitment to cooling urban spaces (10). Using American Forests' Tree Equity Score, the city identified Cesar Chavez Park along Baseline Road as an ideal candidate for this program. As part of the project, 259 drought-resistant, arid-adapted trees were planted along the corridor to create much-needed shade and resilience in the face of rising temperatures (1-3).
Climate-focused activities
Climate change adaptation:
- Increase urban vegetation cover to reduce urban heat island effect
Communities vulnerable to environmental hazards or climate change impacts
Yes
Specification of climate or environmentally vulnerable communities
Urban heat islands, Minority or marginalized ethnic groups
Main beneficiaries
- Citizens or community groups
- Young people and children
- Marginalized groups: Children, young people or youth groups , Socio-economically disadvantaged populations (e.g. low-income households, unemployed), Disadvantaged ethnic or racial groups
Governance
Management set-up
- Co-governance with government and non-government actors
Type of initiating organisation
- Local government/municipality
Participatory approaches/ community involvement
- Co-planning (e.g. stakeholder workshops, focus groups, participatory mapping)
- Joint implementation (e.g. tree planting)
Details on the roles of the organisations involved in the project
The Cool Corridors program in Phoenix is a collaborative effort involving multiple sectors to address urban heat and enhance tree coverage across the city. The City of Phoenix leads the program, coordinating with Neighborhood Services, the Street Transportation Department, Public Works, and Parks & Recreation to facilitate the planting process (1). American Forests, a key NGO partner, has worked with the City to develop a five-year, data-driven planting and preservation strategy for sustainable and targeted tree coverage expansion (1). Significant financial contributions for tree planting events came from private sector partners, including Aspiration, iHeartMedia, and Salesforce, whose support is instrumental to the project’s success (1). Arizona State University also plays an essential role, providing ongoing research and support to optimize the program’s effectiveness (11). Importantly, community members joined in the implementation of the tree planting (11).
Project implemented in response to ...
... an EU policy or strategy?
Unknown
... a national policy or strategy?
Unknown
... a local policy or strategy?
Yes
(As part of its Climate Action Plan Framework, the city of Phoenix aims to create a safe and environmentally conscious network of cool corridors across its communities (8). The department's Cool Corridors program is a part of Phoenix's more comprehensive Tree and Shade Master Plan (8). )
Type of enablers
Governance innovations (such as public private partnerships), City network or regional partnerships focused on climate change, sustainability, GI or NBS in the city, Funds, subsidies or investment for GI/NBS in the city (available for the city or provided by the city)
Financing
Total cost
Unknown
Source(s) of funding
- Public local authority budget
- Corporate investment
Type of funding
- Earmarked public budget
- Direct funding (grants, subsidies, or self-financed projects by private entities)
Non-financial contribution
Type of non-financial contribution
- Provision of labour
Who provided the non-financial contribution?
- Citizens (e.g. volunteering)
Impacts and Monitoring
Environmental impacts
- Climate change
- Lowered local temperature
- Expected lowered local temperature
- Green space and habitat
- Increased green space area
- Achieved increased green space area
- Increased number of species present
- Achieved increased number of species present
Economic impacts
- Generation of other type of work opportunities (e.g. voluntary, work for rehabilitation)
- Achieved generation of other type of work opportunities (e.g. voluntary, work for rehabilitation)
Socio-cultural impacts
- Social justice and cohesion
- Improved liveability
- Expected improved liveability
- Improved access to urban green space
- Achieved improved access to urban green space
- Health and wellbeing
- Improved physical health
- Expected improved physical health
- Safety
- Improved community safety to climate-related hazards
- Expected improved community safety to climate-related hazards
Type of reported impacts
Presence of formal monitoring system
Unknown
Presence of indicators used in reporting
No evidence in public records
Presence of monitoring/ evaluation reports
No evidence in public records
Availability of a web-based monitoring tool
No evidence in public records
Potential risks of implementation and trade-offs
Unknown
References
1.
City of Phoenix (2022). Phoenix Plants First Cool Corridor at Cesar Chavez Park. [Source link];
2.
Loomis, B. (2022). 'Life and death infrastructure': Volunteers plant trees for a new Phoenix 'cool corridor'. [Source link];
3.
Snyder, I. (2022). Hundreds of trees planted at Cesar Chavez Park to create Phoenix's first 'cool corridor'. [Source link];
4.
Breen, P. (2022). Trees planted along Baseline Road in Phoenix. [Source link];
5.
Frederico, J. (n.d.). In low-income Phoenix neighborhoods, the lack of shade trees is a question of equity. [Source link];
6.
Gallego, K. (2023). Towards a More Resilient Phoenix: How One Desert City is Tackling Extreme Heat Challenges. [Source link];
7.
American Forests (n.d.). Phoenix Tackling extreme heat through Tree Equity. [Source link];
8.
City of Phoenix (n.d.). Cool Corridors Program. [Source link];
9.
Estes, C (2021). Phoenix Pledges Tree Equity For All Neighborhoods By 2030. [Source link];
10.
Urban Heat Island & Tree and Shade (UHITS) Subcommittee (2021). City of Phoenix Cool Corridors Program . [Source link];
11.
City of Phoenix (n.d.). About the Program . [Source link];
12.
Maricopa Association of Governments (n.d.). Arizona Demographics . [Source link];
David Gonzalez rakes dirt into a circle around a newly planted tree to help retain water at Cesar Chavez Park on April 16, 2022.
Alex Gould/The Republic
Chavez Park
https://eu.azcentral.com/story/news/local/arizona-environment/2022/04/17/beating-heat-phoenix-plants-first-cool-corridor/7308133001/
Information about this nature-based solution was collected as part of the Naturescapes project funded by the European Union under Grant Agreement No 101084341.