Last updated: October 2021
In 2014, the Marseille Provence Métropole Urban Community commissioned five new stormwater retention basins in order to preserve the quality of coastal waters and reduce the risk of flooding (Ref. 4). In the past, in the event of severe thunderstorms the sewage networks became saturated and a portion of the water was then directly discharged into the sea without going through the sewage treatment plants (Ref. 1). This is seen as "one of the most important documents of recent years in terms of environmental protection. It foresees in the next 5 years, 185 million euros of major works" (Ref. 1).
Marsailles water retention basins
https://www.toutsurmesservices.fr/Bassin-Ganay
Overview
Nature-based solution
- Blue infrastructure
- Coastlines
- Green areas for water management
- Sustainable urban drainage systems
Key challenges
- Water management (SDG 6)
- Flood protection
- Stormwater and rainfall management and storage
- Improvements to water quality
- Coastal resilience and marine protection (SDG 14)
- Coastal protection / hazard mitigation
- Marine and coastal biodiversity protection
- Green space, habitats and biodiversity (SDG 15)
- Habitat and biodiversity conservation
- Environmental quality
- Waste management
- Health and well-being (SDG 3)
- Creation of opportunities for recreation
- Economic development and employment (SDG 8)
- Tourism support
- Employment/job creation
Focus
Coastal landscape management or protection
Project objectives
-"The construction of 5 retention basins will allow to regulate the rain water and to reduce the pollution rate too important" (Ref. 1)
-Avoid runoff water ending in the ocean and prevent people to swim due to pollution (Ref. 1 and 2)
-Preserve the habitat of the aquatic life and their environment (access to food) (Ref. 1)
-Health, Tourism and Economic value (Ref. 2)
-"Preserving the receiving marine environments and revitalizing them at the outlet of the outfall in the calanque de Cortiou, such are the ambitions of the Aix Marseille Provence metropolis across the Ganay basin. Coupled with SUEZ's dynamic rainwater management solutions, it will prevent the discharge of 1 million m3 of untreated wastewater into the Calanques National Park each year. A reduction of 50% compared to the current situation" (Ref. 6).
Implementation activities
"25 operations will be carried out according to a very precise schedule for the period 2014-2018" (Ref. 1)
-Restructuring of the Collector Sud Littoral, and the collectors of the Olives avenue and the Rose avenue. These two operations are important for the protection of bathing water quality.
-Securing and rehabilitating several lifting and collecting stations.
-Modernization of the control system of the sanitation system with the installation of new sensors and real-time modeling.
-Closure of the washing boxes and the installation of greywater pumps in the ports of the territory.
-Actions to preserve or reconquer the natural environment with the setting up of coastal and water-warning stations, measures to promote the progression of cystoseireal algae (providing shelters and food for numerous coastal fish species) in Cortiou, creating shelters for fish in the ports.
-Realization of a set of fundamental studies to guarantee the future evolution of the sanitation system (Ref. 1)
-"In order to preserve the quality of coastal waters and reduce the risk of flooding, the Marseille Provence Métropole Urban Community is implementing a program to modernize the unit network. The project notably includes the construction of a retention basin at the level of Cours Pierre Puget" from 2016-2022 (Ref. 4).
Biodiversity conservation or restoration-focused activities
Biodiversity conservation:
- Protect and enhance urban habitats
- Preserve and strengthen existing habitats and ecosystems
- Reduce negative impacts and avoid the alteration/damage of ecosystem
- Protect species
- Undertake specific measures to protect species
Main beneficiaries
- National-level government
- Local government/Municipality
- Citizens or community groups
Governance
Management set-up
- Co-governance with government and non-government actors
Type of initiating organisation
- Local government/municipality
- Public sector institution
Participatory approaches/ community involvement
- Unknown
Details on the roles of the organisations involved in the project
-"In order to preserve the quality of coastal waters and reduce the risk of flooding, the Marseille Provence Métropole Urban Community is implementing a program to modernize the unit network. The project notably includes the construction of a retention basin at the level of Cours Pierre Puget" from 2016-2022 (Ref. 4).
-€ 185.6 million for the next five years to be financed by MPM (Marseille Provence Métropole), the Seram (Marseille Sewerage Network Operations Company) within the framework of the Public Service Delegation (DSP) and the Water Agency. "In the framework of the DSP, Seram will build a 50,000 m3 storage basin near Géolide. MPM (Marseille Provence Métropole) will be the contracting authority for the creation of the 4 additional basins" (Ref. 2)
The French State is also involved in this project because it is mentioned that "An agglomeration contract signed for the improvement of the sanitation system and the quality of the aquatic environment between the State, MPM and the Water Agency" (Ref. 2) and "The State undertakes to assist the community in carrying out this program" (Ref. 4, page 9). "An agglomeration contract with the Rhône, Méditerranée and Corsica Water Agency was signed. Its objective is to improve the functioning of the sanitation system of the Marseilles conurbation and the quality of its aquatic environments" (Ref. 1). Partners in this project are the local actor Marseille Provence Metropole (Ref. 1).
Project implemented in response to ...
... an EU policy or strategy?
Yes
("To achieve the objectives set by the State and by Europe, MPM (Marseille Provence Metropole) has put in place a program of large-scale work""Meet the new requirements imposed by the European directives on "Water and the marine environment" and "Urban waste water" as well as the new regulatory framework imposed by the State." (Ref. 2)
"the Urban Community has made great efforts to comply with the new European Directives by 2017" (Ref. 1))
... a national policy or strategy?
Yes
("To achieve the objectives set by the State and by Europe, MPM (Marseille Provence Metropole) has put in place a program of large-scale work"."Meet the new requirements imposed by the European directives on "Water and the marine environment" and "Urban waste water" as well as the new regulatory framework imposed by the State." (Ref. 2))
... a local policy or strategy?
Yes
("Objectives of the Agglomeration Contract signed in July 2014 to improve the performance of wastewater treatment in the city and the quality of coastal waters and urban rivers." (Ref. 1 and 3))
Financing
Total cost
More than €4,000,000
Source(s) of funding
- Public regional budget
- 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
Unknown
Impacts and Monitoring
Environmental impacts
- Water management and blue areas
- Improved water quality
- Increased protection against flooding
- Improved stormwater management
- Enhanced protection and restoration of coastal and marine ecosystems
- Other
Economic impacts
- Increase of green jobs (e.g. paid employment positions)
Socio-cultural impacts
- Health and wellbeing
- Gain in activities for recreation and exercise
Type of reported impacts
Expected impacts, Achieved 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
References
1. Métropole Aix Marseille Provence (n.d). "Nous améliorons la qualité des eaux usées". Compétences. (Website not available in 2020).
2. Destimed (2014). "MPM : Un contrat d’agglomération de 185,6 M€ signé pour l’amélioration du système d’assainissement et la qualité du milieu aquatique". Available at: Source link (Accessed: July 30, 2020).
3. Métropole Aix Marseille Provence (n.d). "Bassin de rétention de Ganay". (Website not available in 2020).
4. Egis (n.d). "Bassin de rétention d'eaux unitaires Pierre Puget à Marseille". Available at: Source link (Accessed: July 30, 2020).
5. Métropole Aix Marseille Provence (2014). "Signature du contrat d’agglomération Améliorer le système d’assainissent et la qualité du milieu aquatique". Source link (Website not available in 2020, see attachment).
6. Suez (2017). "Marseille - Bassin de rétention Ganay : un bassin protecteur du Parc National des Calanques". Tout sur mes services. Available at: Source link (Accessed: July 30, 2020).
7. Ignasse, Joël (2017). "Avec le bassin Ganay, Marseille va faire face aux orages". Science et avenir. Available at: Source link (Accessed: July 30, 2020).
2. Destimed (2014). "MPM : Un contrat d’agglomération de 185,6 M€ signé pour l’amélioration du système d’assainissement et la qualité du milieu aquatique". Available at: Source link (Accessed: July 30, 2020).
3. Métropole Aix Marseille Provence (n.d). "Bassin de rétention de Ganay". (Website not available in 2020).
4. Egis (n.d). "Bassin de rétention d'eaux unitaires Pierre Puget à Marseille". Available at: Source link (Accessed: July 30, 2020).
5. Métropole Aix Marseille Provence (2014). "Signature du contrat d’agglomération Améliorer le système d’assainissent et la qualité du milieu aquatique". Source link (Website not available in 2020, see attachment).
6. Suez (2017). "Marseille - Bassin de rétention Ganay : un bassin protecteur du Parc National des Calanques". Tout sur mes services. Available at: Source link (Accessed: July 30, 2020).
7. Ignasse, Joël (2017). "Avec le bassin Ganay, Marseille va faire face aux orages". Science et avenir. Available at: Source link (Accessed: July 30, 2020).