Authorities building a new water supply pumping station upstream a N2000 protected ecosystem in Brittany, France; adaptive management
Sharing water with ecosystems Brittany, France (FR1) Blue Transition – Policy day Area around the Lannenec N2000 area @ABCDrone
P 2 Thinking water as a shared commons supporting both human and non-human living systems. FR1 Area around the Lannenec N2000 area @ABCDrone
Rethinking water governance Land use planning as a lever for climate adaptation “Current” situation @Elias Ganvet P 3 @Elias Ganivet GW level
Diminishing summer rainfall i.e. longer periods without rainfall = towards a more seasonnal climate @Elias Ganvet P 4 Rethinking water governance Land use planning as a lever for climate adaptation @Elias Ganivet
Population increase
- 1% (~1 year) = increasing needs @Elias Ganvet P 5 Rethinking water governance Land use planning as a lever for climate adaptation @Elias Ganivet GW pumping
Population increase
- 10% (~10 year) = increasing needs P 6 Rethinking water governance Land use planning as a lever for climate adaptation @Elias Ganivet GW pumping
Population increase
- 10% (~10 year) Urbanisation = soil sealing = diminishing recharge Objective of FR1: Develop anticipation through prospective modeling to test land- use and water-management options Update regulatory documents guiding urban planning for relevance with future conditions P 7 Rethinking water governance Land use planning as a lever for climate adaptation @Elias Ganivet GW pumping
P 8 System understanding and science-based dialogue between sectors and interests
The challenge of subsurface heterogeneity P 9 Building a new water supply pumping station upstream a N2000 protected ecosystem : towards adaptative management @Hubert Raguet
The challenge of subsurface heterogeneity P 10 @Hubert Raguet Building a new water supply pumping station upstream a N2000 protected ecosystem : towards adaptative management
A drop recharging the aquifer at some specific place : – Is not necessarily reaching the closest stream – Takes ~1000 years to reach directly the ocean P 11 Building a new water supply pumping station upstream a N2000 protected ecosystem : towards adaptative management
Groundwater drawdown linked to the supply station Fractures are by-passes to reach water beyond the watershed P 12 Building a new water supply pumping station upstream a N2000 protected ecosystem : towards adaptative management
Fractures are by-passes to reach water beyond the watershed Pumping captures groundwater flowlines initially feeding the lake P 13 Building a new water supply pumping station upstream a N2000 protected ecosystem : towards adaptative management
The Compromise : linking pumping rate to GW flow in the N2000 ecosystem and climatic contexts Short term measures : Defining a minimum ecological discharge provides decision-makers with a clear operational threshold to balance drinking water supply and ecosystem protection.
- design of an alert observation system P 14 Building a new water supply pumping station upstream a N2000 protected ecosystem : towards adaptative management
P 15 Stakeholders and citizen involvement - raising concern
Sensors make complex processes visible / tangible Measuring together on the field allows to foster dialogue across diverse perspectives P 16 Field scale interactions to connect and hybridize scientific and experiential knowledge
The Open Observatory for place-based research : a meeting point It supports the development of new vigilance and early- warning systems for key water-related risks, including drought, eutrophication and saline intrusion. P 17 Field scale interactions to connect and hybridize scientific and experiential knowledge @Hubert Raguet
In general, curiosity and a sense of wonder prevails, a nature experience also provides a beneficial effects. P 18 Field scale interactions to connect and hybridize scientific and experiential knowledge
P 19 Perspectives
P 20 Transformation of research • Value of the BT network • Scientific questions emerge from a translation of territorials concerns • Ensure the long-term continuation of the open observatory Transformation of local governance • Value of the BT network • Emergence and discussion of new concepts : Territorial carrying capacity Transformation territory-research interactions ●New emerging collaboration on water quality issues and the management of inherited landfills New perspectives based on the Blue Transition experiment
www.cnrs.fr P 21 References Ganivet (2025): Eau et territoires, Enjeux locaux pour une gestion transversale et résiliente, Quae editions Thank you for attention.