69
M
obilisingfinancialresources
Up to now, about €75 000 has been spent on planting flood-breaking hedgerows, including compensation for farmers and
technical studies (about €9 000). Several financial resources have been mobilised for implementing the measure. 20% came
from the SMIVAL itself, which is partly financed by all the municipalities that compose it, and 80% from other partners:
mainly the
Water Agency
and the
French State
, then the Region and the Department and finally Europe (ERDF). One
linear meter of hedgerow is assessed in the Action Programme for Preventing Floods as costing €11, but costs reached €45
to 60 on the pilot sites.
G
overnance
Planting flood-breaking hedges is one of the measures of the
Action Programme for Preventing Floods
in the Lèze
catchment, a French policy tool that aims to prevent and mitigate flood risk. Its implementation is supervised by a Technical
Committee, presided over by the president of the SMIVAL - an association of 24 communes located in the Lèze’s valley.
As the responsible party for leading, defining and implementing actions for qualitative and quantitative use of the Lèze
and for preventing floods, the SMIVAL is the initiator and the responsible party for the implementation of flood-breaking
hedges. As the project concerns cultivated areas, the SIMVAL involved the Chambers of agriculture (representing farmers) in
all the steps linked to agricultural issues (e.g. consultation phase, definition of a land policy) and proposed different types
of
agreements to farmers.
M
ain
impacts
&
benefits
Although no in-depth hydrological analysis has been carried out in order to assess the impact of flood-breaking hedges on
the dynamic of flood events, hydrological models show that covering the Lèze floodplain by regularly spaced flood-breaking
hedgerows can
reduce the peakflow
during flood events by 25%, in comparison to the same floodplain with field crops
only. In reality, hedges already existed in the catchment (about 900km in total) and the project will not be able to create as
dense a network of hedges as assumed in the hydrological modelling. Thus, the impact on peak flow might be lower than 25%
Regarding biodiversity and habitat restoration, no monitoring has been carried out. A
botanical path
has been installed
by the pupils of a local school, which includes interpretation boards presenting the local species constituting the hedges,
and allows people to become familiarised with the ecosystem they are living in. Through this, they are providing a cultural
amenity benefit..
© SMIVAL
Flood-breakinghedgerows
insouthernFrance
Workshops organized with local stakeholders
