Revitalizing the Huveaune river and its biodiversity

1. General information

Location and description of the intervention

City or FUA

Marseille (FUA)

Region

Europe

Native title of the NBS intervention

Revitalisation du fleuve de l’Huveaune et de sa biodiversité

Short description of the intervention

The project to revitalize the Huveaune River and its biodiversity is taking place in Aubagne, a city within the Marseille Metropolitan area. For a long time, the river received little attention, constrained by urbanization, and was even covered for several hundred meters. Urbanization and the construction of a road have made the floodplain more susceptible to flooding (Ref 2). The initiative aims not only to restore the Huveaune and its environment but also to strengthen the connection between residents and the river (Ref 1) while reducing flood risk as a critical objective (Ref 1).
The challenge is transforming the area into a higher-quality environmental space with resilient ecosystems. A diagnostic conducted during the project's design phase revealed the site's degraded state, including the presence of invasive species, steep banks unsuitable for riparian vegetation, poor waterway conservation, and disrupted ecological continuity (Ref 2).
Key actions include revitalizing the river and its biodiversity, removing artificial banks, and creating new meanders to give the river a more natural shape. Diversifying flow patterns will create habitats for aquatic and fish species by varying water heights and flow speeds. This involves increasing the river's sinuosity and varying the width of the minor riverbed (Ref 2). Additional steps include planting trees and shrubs adapted to the Mediterranean climate with low water needs (Ref 2). To bring residents closer to the river, plans include creating walking and cycling routes, sports equipment, educational panels, and useful visitor facilities such as benches, water points, and restrooms (Ref 3).

Website of the intervention

https://www.aubagne.fr/actualite/revitalisation-de-lhuveaune-et-de-sa-biodivers…

Principal problems

Climate-Related Hazards

River flooding

Urban flooding (stormwater)

Environmental Degradation

Biodiversity loss

Invasive alien species

Land use and Socio-economic change

Rapid urbanization

Unequal availability and access to public green spaces

Implementation area characterization

Climate

Temperate ( Humid subtropical, Hot-summer Mediterranean, Warm-summer Mediterranean, Warm-temperate with dry winter)

Ecosystem

Rivers/streams

Urban or built environment

Address

13400 Aubagne
France

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)

Area description

Urban (main city)

Freshwater landscape (e.g. river, lake)

Type of area before implementation of the NBS

Freshwater setting (e.g. river, channel, lake, pond)

Public Greenspace Area

Timeline of intervention

Start date of the intervention (planning process)

2021

Start date of intervention (implementation process)

2023

End date of the intervention

2024

Present stage of the intervention

Ongoing

2. Objectives of the intervention

Objectives of the intervention

Goals of the intervention

1) Environmental restoration and biodiversity enhancement of the river and riverbanks (Ref 1).
2) Improving environmental quality and creating resilient ecosystems (Ref 2).
3) Strengthening the connection between residents and the river (Ref 1).
4) Reducing the risk of flooding (Ref 1, Ref 2).
5) Enhancing the living environment for residents (Ref 2).
6) Promoting public access and recreational use of the river area (Ref 3).
7) Ensuring the project meets the public's needs and expectations through community engagement activities (Ref 2)

Key Priorities

Biodiversity (conservation and/or restoration)

Sustainability challenge(s) addressed

Green space, habitats and biodiversity (SDG 15)

Green space creation and/or management

Habitat and biodiversity restoration

Water management (SDG 6)

Flood protection

Stormwater and rainfall management and storage

Health and well-being (SDG 3)

Creation of opportunities for recreation

Enabling opportunities for physical activity

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

Species-focused

Ecosystem-focused

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

Restore species (native, endangered, or unspecified)

Restore native species

Clear and control invasive alien species

Public engagement

Implementation activities and NBS focus

Implementation activities

Environmental restoration and biodiversity enhancement:
- Conduct seasonal inventories of fauna and flora until summer 2024 (Ref 2).
- Plant a grove of 300 shrubs (Ref 2).
- Remove artificial riverbanks to restore natural ones where possible (Ref 2).
- Soften the slope of the banks to ensure natural stability and reestablishment of a wide, diverse riparian zone that ensures ecological, continuity and renewal (Ref 2).
- Diversify flow patterns to create habitats for aquatic and fish species by varying water heights and flow speeds through increased river sinuosity and varying the width of the riverbed (Ref 2).
- Vegetate the entire park with species adapted to the Mediterranean climate, using rapid vegetation development techniques (Ref 3).
- fight against invasive species by restoring native species (Ref 2)

Urban and public space development:
- De-impermeabilize the plaza of the Espace des Libertés (Ref 2).
- De-impermeabilize and enhance the basin in the Botte Park (Ref 3).
- creation of walk trails and bicycle routes (Ref 1)
- Install useful visitor facilities, such as benches, water points, and restrooms (Ref 3).
- Develop spaces for relaxation and leisure, including sports areas and children's playgrounds (Ref 3).
- Ensure accessibility for people with reduced mobility (Ref 3).
- Install observation decks and educational panels (Ref 2).

Community engagement:
- public meetings and consultations (Ref 2)
- proposition of several scenarios (Ref 2)

Type of NBS project

Maintenance and management of urban nature

Maintenance or upgrade of exisiting green spaces (e.g. parks)

Management and improved protection of rivers and other blue areas

River rehabilitation/ restoration

Restoration, protecion and sustainable manage floodplains

Restoration of riparian vegetation

Ecological restoration of ecosystems

Ecological restoration of existing green spaces

Restoration and protection of ecosystems (including water ecosystems)

Monitoring and maintenance of habitats and/or biodiversity

Clearing out invasive alien species and allow natural regeneration maintaining the functionality the ecosystem

Species-specific monitoring and conservation 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

Riverbank/Lakeside greens

Green areas for water management

Sustainable urban drainage systems

Parks and urban forests

Pocket parks/neighbourhood green spaces

Amenities offered by the NBS

Benches and drinking water stations

Playgrounds

Sports areas and equipment

Educational or biodiversity trails

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)

Services

Expected ecosystem services delivered

Regulating services

Flood regulation

Water purification / filtration

Habitat and supporting services

Habitats for species

Cultural services

Aesthetic appreciation

Recreation

Mental and physical health and wellbeing

Scale

Spatial scale

Micro-scale: District/neighbourhood level

Beneficiaries

Demographics in implementation area

Demographics in Aubagne in 2021 (Ref 6)
- population: 47 342
- median income: 22 550
- poverty rate: 16%
- average age: 42.33
- no ethnicity statistics in France

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

Communities located in floodplains

Primary Beneficiaries

Citizens or community groups

Young people and children

Specify primary beneficiaries

- the residents: "to improve [...] the living environment of residents" (Ref 2)
- the users of the highschool located in the floodplain "reduce flood risk at Lycée Joliot-Curie" (Ref 3)

Marginalized groups

Unknown

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

Government-led

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

- Project led by the city of Aubagne and the Metropole Aix-Marseille-Provence and partnered with EPAGE (public water development and management establishment) HuCA (Huveaugne, côtier, aygalages) (local public agency)
- Consultation and engagement of the public

Key actors - initiating organization

Local government/municipality

Key actors - Other stakeholders involved (besides initiating actors)

Public sector institution

Citizens or community group

Stages of citizen and community engagement

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

Decision-making among different alternative plans

Feedback during project implementation (e.g. review sessions)

Level of citizen and community engagement

Moderate

Community empowerment or capacity-building initiatives

Unknwon

Participatory methods/forms of stakeholder involvement (all stakeholders)

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

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

Citizen monitoring and review

Uncommon actors ("Missing actors")

Other

Please specify other missing actor

Public Services: Public water institution

Land owners

Public space owned by the city

Policy drivers

NBS intervention implemented in response to a Regional Directive/Strategy

Unknown

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

Unknown

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

Unknown

Mandatory or voluntary intervention

Unknown

Enablers & Barriers

Type of enablers

Capacity-building projects

Governance innovations (such as public private partnerships)

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

The project had been built and implemented with several stages of consultation with the public (Ref 2)

Governace and decison-making instruments

Strategic instruments (e.g. GI strategies, green space strategy or plans)

Public - community agreement (e.g. citizen science programs; citizen assemblies)

Arrangements for governance cooperation

Formal coordination mechanisms to oversee project implementation and decision-making (e.g., multi-stakeholder steering committees, working groups)

Barriers

There was strong opposition to the project in a specific area, Botte Park, particularly against the tree removal. This forced the city to revise its plan, reducing the number of trees to be cut from 200 to 40. However, with fewer trees removed, the ability to widen the river and restore biodiversity was also reduced. (Ref 5)

Financing

Total cost

Unknown

Please specify total cost (EUR)

unknown

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

unknown

Source(s) of funding

Public local authority budget

Type of fund(s) used

Earmarked public budget

Non-financial contribution

Unknown

Co-finance for NBS

Unknown

Entrepreneurship opportunities

Unknown

Business models

Green densification model

Which of the involved actors was motivated by this model?

Public actor (e.g. municipality)

5. Evaluation and learning

Impacts, benefits

Environmental impacts

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 green space area

Expected increased green space area

Increased conservation or restoration of ecosystems

Expected increased conservation or restoration of ecosystems

Increased ecological connectivity across regeneration sites and scales

Expected increased ecological connectivity across regeneration sites and scales

Increased number of species present

Expected increased number of species present

Improved prevention or control of invasive alien species

Expected improved prevention or control of invasive alien species

Description of environmental benefits

-Increased protection against flooding: the project will "Give space back to the Huveaune, while optimizing flood risk reduction for current floods" (Ref 2)
-Enhanced protection and restoration of freshwater ecosystems: "create habitat for aquatic and fish fauna" (Ref 2)
-Increased green space area: "Planting a grove of 300 shrubs" "A planting site to showcase a high-density grove in the Parc de la Botte in February 2024" (Ref 2) "Revegetation of the entire park: planting of numerous species adapted to the Mediterranean climate" (Ref 3)
-Increased conservation or restoration of ecosystems: "The challenge is to make it a much more qualitative place from an environmental point of view, with resilient ecosystems, which is not the case today." (Ref 2) "The aim of the project is [...] to create a new green space in Aubagne town center." (Ref 4)
-Increased ecological connectivity across regeneration sites and scales: "allow exchanges/connections between the river and the major water bed for wildlife" (Ref 2)
-Increased number of species present: "The seedlings planted come from a local nursery and have been selected to guarantee plant development in a Mediterranean climate. The choice of species is based on a selection of Mediterranean species with low water requirements. The selection includes tree, shrub and sapling species, favoring an ecologically rich forest." (Ref 2)
-Improved prevention or control of invasive alien species: "The challenge is to make it a much higher-quality site from an environmental point of view, with resilient ecosystems, which is not the case today. The diagnosis carried out during the design stages of the project established the degraded state of the site: presence of invasive species" (Ref 2)

Environmental impact indicators

Total number of vascular plant species protected or introduced

unknown

Green space area created (in ha)

unknown

Total area of habitat restored (in ha)

unknown

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

unknown

Water retention capacity (m³ or %)

unknown

Area of water management infrastructure (e.g. SUDs, rain gardens) (m2)

unknown

Economic impacts

Unknown

Description of economic benefits

unknown

Social and cultural impact indicators

Surface area of accessible green spaces (in ha)

unknown

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

unknown

Number of environmental education programs, workshops, outreach activities (eg. in schools, community centers, public spaces)

unknown

Mental health benefits

Restoration and relaxation

Increased feelings of nature connection

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

Local government/municipality

Citizens or community group

Presence of indicators used in reporting

Yes

Type of indicators

Output indicators

Progress indicators

Presence of monitoring/evaluation reports

No evidence in public records

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

Meetings with stakeholders’ representatives

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

Justice

Community satisfaction

Mixed: Feedback and reports show a combination of positive and negative sentiments regarding satisfaction with the NBS project within the community.

Description of locals satisfaction with the project

There was strong opposition to the project in a specific area, Botte Park, particularly against the tree removal. This forced the city to revise its plan. An agreement has been found to reduce the number of trees to be cut from 200 to 40 (Ref 5).

Trade-offs & Negative impacts

Unknown

Measures to prevent gentrification or displacement

Unknown

High-quality & Transformative NBS

Multiple impacts delivery (climate, biodiversity, just community)

Goal setting and impacts delivery

No, project goals were not set, and benefits were not delivered in all 3 key areas.

Reaching original project goals

Inconclusive as the project is still undergoing implementation, or is still on its planning stages

Long-term perspective

Yes

Cost-effective solutions

Unknown

Equitable impacts

C. Unknown

Transformative capacity

Systemic change (the NBS caused changes across the social, ecological and technological dimensions)

Magnitude of change

Transformative: (deep) by focusing on and substantially changing structures, including institutional ones (norms and rules).

Application of lessons learned

Unknown

Perception of Environmental Change

Unknown

6. Sources

References

City of Aubagne (2024). Revitalisation de L’Huveaune et de sa biodiversité : concertation jusqu’au 21 juin. Aubagne: City of Aubagne, p. 1 Accessed on September 6, 2024, [Source link] [Archive];

EPAGE HUCA (n.d.). Parc de l’Huveaune – Projet de revitalisation du fleuve et de sa biodiversité. Aubagne: EPAGE HUCA, p. 1-5 Accessed on September 6, 2024, [Source link] [Archive];

EPAGE HUCA (2024). Le Parc de l’Huveaune en centre-ville Revitalisation du fleuve et de sa biodiversité . Aubagne: EPAGE HUCA, p. 1-24 Accessed on September 6, 2024, [Source link] [Archive];

Le Moniteur (2023.). Bouches-du-Rhône : lancement des travaux de création du parc de l’Huveaune, à Aubagne. Aubagne: Le Moniteur, p. 1-2 Accessed on September 6, 2024, [Source link] [Archive];

DISDIER, I. (2024.). "Un consensus" trouvé, le projet du parc de l'Huveaune verra bien le jour à Aubagne. Aubagne: La Provence, p. 1 Accessed on September 6, 2024, [Source link] [Archive];

INSEE (2021). demographics in Aubagne. Aubagne: INSEE, Accessed on September 6, 2024, [Source link] [Archive];

Comments and notes

Public Images

Parc de l'Huveaune - Project to revitalize the river and its biodiversity

https://www.laprovence.com/article/region/23506155289400/un-consensus-trouve-le-projet-du-parc-de-lhuveaune-verra-bien-le-jour-a-aubagne accessed on 06/09/2024

meander creation plan for the Huveaune park

https://www.epagehuca.fr/wp-content/uploads/2023/10/PPT-restitution-19.06.2024.pdf accessed on 06/09/2024

The example of a renaturation project for the Huveaune and its surroundings.

Ref. 2: Photos of the Confluence park in Auriol (July 2023)