The Rio Salado Habitat Restoration Area

1. General information

Location and description of the intervention

City or FUA

Phoenix (FUA)

Region

Northern America

Short description of the intervention

The Rio Salado Habitat Restoration Area is a urban green space that transformed a former 5-mile-long city dump into a thriving riparian corridor (2, 3, 7, 9). The project, spearheaded by the City of Phoenix in collaboration with the U.S. Army Corps of Engineers, Maricopa County Flood Control District, and the Arizona Water Protection Fund, has revitalized a degraded ecosystem (9). Through decades of concerted effort, involving government agencies, non-profits such as the Arizona Sustainability Alliance, and community engagement, the area has been restored to a lush habitat supporting diverse wildlife, including over 200 bird species (1, 2, 7). The project aimed to mitigate the pressing issues of urban heat, air pollution, and habitat loss that Phoenix grappled with (1). By creating green spaces, improving air quality, and offering recreational opportunities, the Rio Salado Habitat Restoration Area stands as a testament to the power of collaborative conservation and community resilience (1, 6, 7, 9). The restoration area now boasts hiking and biking trails, a nature center, and various educational programs, making it a community space (3, 7, 9).

Website of the intervention

https://www.phoenix.gov/pddsite/Documents/PZ/pdd_pz_pdf_00064.pdf#search=e%20Ri…

Principal problems

Climate-Related Hazards

Heat stress & Extreme temperatures

Environmental Degradation

Biodiversity loss

Air pollution

Implementation area characterization

Climate

Arid (Desert, Steppe)

Ecosystem

Deserts

Fresh water wetlands

Rivers/streams

Address

2439 S Central Ave
Phoenix, 85004
United States

Location

The NBS area is spread over a linear space, the GIS coordinates serve as points along a line (e.g. along a river)

Area boundary (map-based)

Total area

2407880.00m²

NBS area

2407880.00m²

Area description

Urban (main city)

Type of area before implementation of the NBS

Waste disposal site or landfill

Timeline of intervention

Start date of the intervention (planning process)

1997

Start date of intervention (implementation process)

2000

End date of the intervention

unknown

Present stage of the intervention

Completed

2. Objectives of the intervention

Objectives of the intervention

Goals of the intervention

1. To address biodiversity loss of the area by restoring the native wetland and riparian (riverbank) areas which provides habitats for over 200 species that were historically associated with the Salt River (3, 4, 5, 7, 8, 9)
2. To provide a river ecosystem to achieve a sustainable balance of flora and fauna (6, 9)
3. To confer a seasonal migratory path for birds, maintain marshlands and irrigate some trees and bushes (4, 7, 9)
4. To reduce temperatures substantially, improve air quality, sequestering carbon by adding additional shade cover (1,6)
5. To increase canopy cover to reduce temperatures and provide health benefits for the community (1, 6)
6. To address water management issues by planting trees to reduce storm water runoff (1, 7)
7. To provide a variety of spaces for the community from 16 km of trails, a center for education (due to lack of recreational opportunities) and an opportunity to engage with wildlife (7)

Key Priorities

Climate action (adaptation and/or mitigation)

Biodiversity (conservation and/or restoration)

Sustainability challenge(s) addressed

Climate action for adaptation, resilience and mitigation (SDG 13)

Climate change adaptation

Climate change mitigation

Environmental quality

Air quality improvement

Green space, habitats and biodiversity (SDG 15)

Habitat and biodiversity restoration

Water management (SDG 6)

Stormwater and rainfall management and storage

Health and well-being (SDG 3)

Creation of opportunities for recreation

Enabling opportunities for physical activity

Social justice, cohesion and equity (SDG 10)

Environmental education

Climate change adaptation: What activities are implemented to realize the conservation goals and targets?

Increase urban vegetation cover to reduce urban heat island effect

Restore mangroves, marshes, reefs and wetlands to dissipate the effects of storms and floodwaters

Restore and protect forests to prevent water runoff and assets loss due to flooding

Climate change mitigation: What activities are implemented to realize the conservation goals and targets?

Increase the availability of green urban space for carbon storage (street tree cover)

Protect and restore in-land wetlands, peatlands, swamps, and moors aiming at sequestering carbon dioxide and storing it in their soil

Improve carbon sequestration through selection of more adaptable species

What types of restoration goals are / were defined for the NBS intervention?

Ecosystem-focused

What activities are implemented to realize the restoration goals and targets?

Rehabilitate and restore damaged or destroyed ecosystems

Restore species (native, endangered, or unspecified)

Restore native species

Public engagement

Implementation activities and NBS focus

Implementation activities

The project implemented several key activities to achieve its goals and address the existing problems in the area:
1. Waste Removal: Over 138,572 cubic yards of waste and 1,185 tons of tires were removed from the site, cleaning up the heavily polluted area (7, 9-10).
2. Habitat Restoration: 76,000 trees, plants and shrubs, including a Monarch butterfly sanctuary with willows, sages and milkweed. Most of the native trees were grown from seeds and cuttings gathered from within a half mile of the river bottom (7, 9-10).
3. Riparian Habitat Creation: Wetlands were established to mimic the historical habitat along the Salt River (2-10).
4. Trail Development: A network of trails was created for hiking, biking, and walking, providing recreational opportunities for the public (2-10).
5. Educational Programs: Programs were developed to educate the public about the importance of riparian habitats and environmental conservation (2).
6. Water Management: Planting trees to reduce storm water runoff and installed 5 pumps to maintain the marshlands and irrigate trees and bushes (1, 7)
7. Community Engagement: 6 public workshops were organized discuss land use preferences and gain input from area residents, public meetings were held to present information (9).

Type of NBS project

Creation of semi-natural blue areas

Creation of artificial wetlands

Management and improved protection of rivers and other blue areas

River rehabilitation/ restoration

Restoration of riparian vegetation

Protection of natural ecosystems

Protecton and enhancement of wetlands (other types than peatlands and mangroves, e.g. seagrass)

Habitat restoration

Creating nature reserves, wildlife sanctuaries, or biodiversity hotspots to conserve unique ecosystems

Transformation of previously derelict areas

Landfill reclamation

Knowledge creation and awareness raising

Educational and awareness raising programs

3. NBS domains, ES and scale

NBS domain and interventions

Ecological domain(s) where the NBS intervention(s) is/are implemented

Blue infrastructure

Rivers/streams/canals/estuaries

In-land wetlands, peatlands, swamps, and moors

Riverbank/Lakeside greens

Amenities offered by the NBS

Benches and drinking water stations

Educational or biodiversity trails

Educational and research amenities (nature protection centre, monitoring stations)

Complementing infrastructure (bathrooms, café)

Viewing and outlook points

Design elements for well-being

Visual elements (e.g., expansive views, scenic views, natural light, diverse vegetation)

Auditory elements (e.g., birdsong, water features, quiet areas, rustling leaves)

Olfactory elements (e.g., floral scents, earthy smells)

Tactile elements (e.g., natural materials like wood or stone, exposure to sunlight)

Services

Expected ecosystem services delivered

Regulating services

Local climate regulation (temperature reduction)

Air quality regulation

Carbon storage/sequestration

Habitat and supporting services

Habitats for species

Cultural services

Aesthetic appreciation

Recreation

Intellectual interactions (scientific and / or educational)

Physical and experiential interactions with plants and animals

Scale

Spatial scale

Micro-scale: District/neighbourhood level

Beneficiaries

Demographics in implementation area

The park is located in the southern outskirts of downtown Phoenix. According to the City of Phoenix zoning map, directly surrounding the park are industrial areas with general commercial spaces, with a limited multi-family residential area (9). In 2000, 56% of the population is between the ages of 18 & 54 (9). In 2000, 56% of the population was identified as white, followed by 34% identifying as hispanic (9). In 1999, the average household income in the area was $31,093 (9). Phoenix is the hottest metropolitan area in the country so many neighborhoods face severe temperatures affecting overall health (1).

Socio-economic profile of the area

Middle-income

Communities vulnerable to environmental hazards or climate change impacts

Yes

Specification of climate or environmentally vulnerable communities

Urban heat islands

Non-government actors

Non-governmental organisation (NGO) / Civil society / Churches

Researchers, university

Citizens or community groups

Primary Beneficiaries

Citizens or community groups

Marginalized groups

Specify primary beneficiaries

-Citizens or community groups: The Nina Mason Pulliam Rio Salado Audubon Center serves as the park’s nature center. Admission is free. Among other programs, the center offers interactive exhibits, birding classes, and an interpretive loop trail with connections to the Rio Salado Habitat Restoration Area's trails. The center also helps to connect students and volunteers to the park (2, 7).
-Marginalized groups: Phoenix is the hottest metropolitan area in the country. On some days, there are neighborhoods that are as much as 13 degrees Fahrenheit hotter than others. The hottest neighborhoods also have the least number of trees and the highest child poverty (1).

Marginalized groups

Socio-economically disadvantaged populations (e.g. low-income households, unemployed)

Measures for inclusion of marginalised groups

The project's actors partnered in 2021 and established the Urban Heat Leadership Academy that works to address sustainability challenges related to urban heat, air quality and water and get hands-on experience implementing solutions to help inform neighborhoods that may not be aware of the role that nature can play in reducing heat and improving quality of life(1)

Specify measures taken for vulnerable or marginalized communities

Targeted outreach and engagement efforts with vulnerable or marginalized communities to understand concerns or identify risks

Other beneficiaries

Local wildlife (e.g., birds, pollinators)

Native plant vegetation

Natural habitats (e.g. wetland, forests, coastal areas)

Ecosystem services (e.g. improved air quality, water purification)

4. Governance and financing

Governance

Governance arrangements

Co-governance with government and non-government actors

Please specify the roles of the specific government and non-government actor groups involved in the initiative

Government :
-U.S. Army Corps of Engineers: Led the project, co-designed and provided technical expertise and funding (9).
-City of Phoenix: co-designed and partnered with the ACOE and provided funding and support (9)
-Rio Salado Development District: A government entity created to oversee the project (9).
-Maricopa County Flood Control District: Provided technical and financial assistance (9).
-Sub-Regional Operating Group Members: The cities of Scottsdale, Tempe, Glendale, and Mesa contributed funding and support (9).
NGO: Valley Forward Association: A non-profit organization that played a key role in early planning efforts (9).
University: Arizona State University: Conducted early studies and provided academic support (9).
Citizens: public workshops were organized to discuss land use preferences and gain input(9

Key actors - initiating organization

National government

Local government/municipality

Non-government organisation/civil society

Key actors - Other stakeholders involved (besides initiating actors)

Regional government

Citizens or community group

Researchers/university

Stages of citizen and community engagement

Planning and design (e.g. site selection, identification of key priorities)

Decision-making among different alternative plans

Level of citizen and community engagement

Moderate

Community empowerment or capacity-building initiatives

Implementation of educational programs, workshops or trainings

Creation of collaborative decision-making processes that actively involve community members

Participatory methods/forms of stakeholder involvement (all stakeholders)

Co-planning (e.g. stakeholder workshops, focus groups, participatory mapping)

Taskforce groups

Dissemination of information and education

Consultation (e.g. workshop, surveys, community meetings, town halls)

Joint implementation (e.g. tree planting)

Uncommon actors ("Missing actors")

Public Services

Ministry of Defence / military and law enforcement authorities

Land owners

Public space owned by the city

Policy drivers

NBS intervention implemented in response to a Regional Directive/Strategy

Yes

Please specify the "Regional Directive/Strategy"

The project is part of the Water Resources Development Act (9).

NBS intervention implemented in response to a national regulations/strategy/plan

Yes

Please specify the national regulations/strategy/plan

The tree planting project is part of the UN Sustainable Development Goals (1)

If there is a relevant strategy or plan, please specify the theme/type of the plan

SDGs National Strategy

NBS intervention implemented in response to a local regulation/strategy/plan

Yes

Please specify the "local regulation/strategy/plan"

Arizona state law required that each city to adopt a General Plan to guide the physical development of the community. Based on this, the city issued the Rio Salado Beyond the Banks Area Development Plan, which focuses on flood control, habitat restoration, promoting development in the area, and establishing connections to trails, parks, and transportation systems of which the Rio Salado Habitat Restoration Project is part of (9,11).

Relevant strategy or plan

Municipal / city level environmental plan or programme

General municipal plan

Mandatory or voluntary intervention

Mandatory (based on policy)

Intervention is mandatory

Environmental regulation

Enablers & Barriers

Type of enablers

Funds, subsidies or investment for GI/NBS in the city (available for the city or provided by the city)

Please provide details (e.g, name of the plan or strategy) for the selected policies or initiatives.

City of Phoenix's urban greening and sustainability initiatives, state-level water management policies, Federal environmental protection regulations (11).

Governace and decison-making instruments

Legislative and regulatory instruments (e.g. laws, strategies, regulations or restrictions)

Economic and fiscal instruments (e.g. subsidies or grants, charges or fees, payments for ecosystem services (PES))

Educational and knowledge sharing instruments (e.g. science/ living labs, awareness raising campaigns, specific educational programs, green hubs)

Arrangements for governance cooperation

Unknown

Barriers

Unknown.

Financing

Total cost

More than €4,000,000

Please specify total cost (EUR)

84, 642, 667.35 (6, 9)

What is/was the Cost/Budget (EUR) of the NBS or green infrastructure elements?

Unknown

Source(s) of funding

Public local authority budget

Public national budget

Public regional budget

Type of fund(s) used

Direct funding (grants, subsidies, or self-financed projects by private entities)

Non-financial contribution

Yes

Who provided the non-financial contribution?

Public authorities (e.g. land, utility services)

Citizens (e.g. volunteering)

Type of non-financial contribution

Provision of land

Provision of labour

Provision of expertise

Co-finance for NBS

Yes

Co-governance arrangement

A fund / grant

Entrepreneurship opportunities

Unknown

Business models

Risk reduction model

Urban offsetting model (biodiversity or water)

Which of the involved actors was motivated by this model?

Public actor (e.g. municipality)

Private non-for-profit actor (e.g. NGO, foundation)

5. Evaluation and learning

Impacts, benefits

Environmental impacts

Climate change

Prevent the frequency and/or intensity of heatwaves

Expected prevent the frequency and/or intensity of heatwaves

Environmental quality

Improved air quality

Expected improved air quality

Improved waste management

Achieved improved waste management

Water management and blue areas

Increased protection against flooding

Expected increased protection against flooding

Enhanced protection and restoration of freshwater ecosystems

Expected enhanced protection and restoration of freshwater ecosystems

Green space and habitat

Increased conservation or restoration of ecosystems

Expected increased conservation or restoration of ecosystems

Reduced biodiversity loss

Achieved reduced biodiversity loss

Increased number of species present

Achieved increased number of species present

Description of environmental benefits

1. Prevent the frequency and/or intensity of heatwaves: "By adding these 45 trees, the project will enhance the park’s shade canopy, mitigating the metropolitan heat island effects and offering thermal refuge for future generations of community members to enjoy walks and bike rides through the park in comfort." (6)
2. Improved air quality: "Increasing tree and shade canopy cover by planting the right tree, in the right place and with the right water to improve air quality." (1, 6)
3. Achieved waste management: "To create the park, the city removed 1,185 tons of tires and 138,572 cubic yards of trash. " (7)
4. Increased Protection against flooding: "The Rio Salado Project will create additional flood-control capacity by constructing a permanent channel into the river to carry small, frequent stream flows and to minimize impacts from
occasionally damaging floods." (9)
5. Enhanced protection and restoration of freshwater ecosystems: "Five groundwater pumps were added to the site. The pumps create a riparian pond at the park’s Central Gateway at South Central Avenue just south of East Watkins Street. The pumps also maintain marshlands and irrigate some trees and bushes. " (7)
6. Increased conservation or restoration of ecosystems: "The goal of the Phoenix Rio Salado Habitat Restoration Area is to restore the native wetland and riparian (riverbank) habitats that were historically associated with the
Salt River." (3)
7. Reduced biodiversity loss: "More than 200 species of birds, including 50 burrowing owls, roadrunners, ducks, herons and egrets. There also are beavers, fish, turtles, snakes and toads." (7)
8. Increased number of species present: "Bird watchers have spotted more than 200 species of birds (and counting...) in Rio Salado's varied habitats from wetland ponds to mesquite bosque to cottonwood/willow forest." (2)

Environmental impact indicators

Total number of vascular plant species protected or introduced

76,000 trees were planted in 2014 (7) & 45 trees planted in 2023 (6)

Total number of bird species re-introduced, rediscovered or monitored

200

Total area of habitat restored (in ha)

235.52

Total area of protected or secured natural areas (in ha)

235.52

Area of river/lake or riparian area restored (in ha)

235.52

Water supplied or available from nature restoration (in m³ or L)

13.7 millon

Economic impacts

Unknown

Description of economic benefits

Unknown

Social and cultural impact indicators

Surface area of accessible green spaces (in ha)

Total area of recreational green space created or restored (in ha)

Evidence for use of assessment

Presence of an assessment, evaluation and/or monitoring process

Yes

Actors involved in the assessment, monitoring or evaluation of NBS impacts

Non-government organisation/civil society

Presence of indicators used in reporting

Yes

Type of indicators

Presence of monitoring/evaluation reports

Yes

Link to monitoring/evaluation reports

https://www.cityforestcredits.org/impact-certification/impact-directory/phoenix…

Availability of a web-based monitoring tool

No evidence in public records

Name of any specific impact assessment tools

Unknown

Use of GIS in mapping impacts

No evidence in public records

Cost-benefit analysis

Unknown

Transparency

Inclusion of diverse stakeholders in project governance processes (e.g. planning, implementation, monitoring, etc.)

Clear communication channels for stakeholders to provide feedback, raise concerns, and ask questions about the project

Online disclosure of technical reports (e.g. project documents, reports, or data)

Justice

Community satisfaction

Unknown

Description of locals satisfaction with the project

Unknown.

Trade-offs & Negative impacts

Unknown

Measures to prevent gentrification or displacement

Unknown

High-quality & Transformative NBS

Multiple impacts delivery (climate, biodiversity, just community)

Yes

Goal setting and impacts delivery

Yes, from the planning phase the project aimed to address issues in these three key priority areas and it also delivered benefits across these three areas.

Reaching original project goals

Most of the project goals were achieved

Please specify the achievements of the project goals

Biodiversity Goals:
1. Increased conservation or restoration of ecosystems: "The goal of the Phoenix Rio Salado Habitat Restoration Area is to restore the native wetland and riparian (riverbank) habitats that were historically associated with the
Salt River." (3)
2. Reduced biodiversity loss: "More than 200 species of birds, including 50 burrowing owls, roadrunners, ducks, herons and egrets. There also are beavers, fish, turtles, snakes and toads." (7)
3. Increased number of species present: "Bird watchers have spotted more than 200 species of birds (and counting...) in Rio Salado's varied habitats from wetland ponds to mesquite bosque to cottonwood/willow forest." (2)

Climate action goals:
1. Prevent the frequency and/or intensity of heatwaves: "By adding these 45 trees, the project will enhance the park’s shade canopy, mitigating the metropolitan heat island effects and offering thermal refuge for future generations of community members to enjoy walks and bike rides through the park in comfort." (6)
2. Improved air quality: "Increasing tree and shade canopy cover by planting the right tree, in the right place and with the right water to improve air quality." (1, 6)
3. Achieved waste management: "To create the park, the city removed 1,185 tons of tires and 138,572 cubic yards of trash. " (7)
4. Increased Protection against flooding: "The Rio Salado Project will create additional flood-control capacity by constructing a permanent channel into the river to carry small, frequent stream flows and to minimize impacts from
occasionally damaging floods." (9)

Long-term perspective

Yes

Cost-effective solutions

Unknown

Equitable impacts

C. Unknown

Transformative capacity

Ecological change (e.g. ecosystem functions and their distribution)

Magnitude of change

Incremental: shallow; that is, mostly maintaining business-as-usual approaches to adaptation

Application of lessons learned

Unknown

Perception of Environmental Change

Yes

NBS Supports ecological or environmental anxiety

Unknown

6. Sources

References

The Nature Conservancy (n.d.). Addressing Heat and Air Quality in Phoenix. [Source link] [Archive];

Rio Salado Audubon Center (n.d.). The Rio Salado Habitat Restoration Area. [Source link] [Archive];

City of Phoenix (n.d.). Rio Salado Habitat Restoration Area. [Source link] [Archive];

Greater Phoenix Orienteering Club (n.d.). Rio Salado Habitat Restoration Area. [Source link] [Archive];

City Forest Credits (n.d.). Rio Salado Habitat Restoration Area AMEX Planting. [Source link] [Archive];

Kathleen Ferris (n.d.). Rio Salado Habitat: Wildlife Sanctuary Created From Wasteland. [Source link] [Archive];

Arizona Department of Environmental Quality (n.d.). PROPOSED ARIZONA POLLUTANT DISCHARGE ELIMINATION SYSTEM (AZPDES) RENEWAL PERMIT. [Source link] [Archive];

City of Phoenix Planning Department (2003). Rio Salado Beyond the Banks Area Plan. Phoenix, Arizona: [Source link] [Archive];

10.

U.S. Environmental Protection Agency (EPA) (n.d.). Rio Salado Oeste Urban Waters Technical Assistance Report - Vision, Goals and Strategies for Revitalization. Phoenix : [Source link] [Archive];

11.

Visit Phoenix (n.d.). Thinking Ahead Sustainably . [Source link] [Archive];

Comments and notes

Public Images

The Rio Salado Habitat Restoration Area

Rio Salado Audubon Center

Volunteers from American Express in Phoenix helped with a planned tree planting along the Rio Salado Preserve

The Nature Conservancy