---
title: "Authorities building a new water supply pumping station upstream a N2000 protected ecosystem in Brittany, France; adaptive management"
sdDatePublished: "2026-05-23T13:22:00Z"
source: "https://www.interregnorthsea.eu/sites/default/files/2026-05/2_20260519%20-%20BT%20Lorient.pdf"
topics:
  - name: "environment"
    identifier: "medtop:06000000"
  - name: "water supply"
    identifier: "medtop:20000270"
  - name: "government policy"
    identifier: "medtop:20000621"
  - name: "sustainability"
    identifier: "medtop:20001374"
locations:
  - "France"
---


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.