11
Whatmakesameasure aNaturalWaterRetentionMeasure?
NaturalWater Retention Measures or NWRM are measures with the primary
functionof enhancing and/or restoring the retention capacity of natural andman-
made soil and aquatic ecosystems. As a result, they deliver a range of services
and multiple benefits to people while contributing to the achievement of the
objectives of different environmental strategies and policies.
As defined in the EU policy document onNWRM (see Box 1
11
),NWRM
ņ
ņ
Retainwater
(runoffor riverflows)beyond theexistingcapacityof systems,
releasing it at a controlled rate,or infiltrating it to groundwater
12
;
ņ
ņ
Use the retention capacity of soils and of aquatic ecosystems to
provide
other environmental andwell-being improvements
, such as water quality,
biodiversity, amenity value or resilience and adaptation to climate change
impacts;
ņ
ņ
Are usually applied at relatively
‘small scale’,
in comparison to the size of
thewater catchment or territory inwhich they are implemented;
ņ
ņ
Emulate a
natural process
, although are not always ‘natural’ features
themselves (as clearly illustrated by green roofs).
The definition of NWRM appeals both to a single purpose (safeguarding,
enhancing or restoring thewater storage potential) and also to a particular set of
means (using natural processes).The actual distinctive character ofNWRMhas to
dowith the latter.
11
EuropeanCommission. 2014. EU policy document onNaturalWater RetentionMeasures. By the drafting team
of theWFDCISWorkingGroup Programme of Measures (WG PoM)
12
Note that not everymeasure that increases thewater stored inwater bodies is aNWRM.Alternatives such as
water saving options,water efficiencymeasures,wastewater treatment, demandmanagement and others that might
result in an improvement of water bodies and of their water retention potential may not be considered asNWRM.
ThedefinitionofNWRMasprovided in theEUpolicydocument
Natural Water RetentionMeasures are
multi-functional measures
that aim to protect water
resources and addresswater-related challenges by
restoringormaintaining ecosystems
aswell
as
natural featuresandcharacteristics
ofwaterbodiesusing
naturalmeansandprocesses
.
The main focus of applying NWRM is to
enhance the retention capacity of aquifers, soil, and
aquatic andwater dependent ecosystems
with a view to improve their status. The application
of NWRM supports
green infrastructure
, improves the
quantitative status of water bodies
as
such, and reduces the
vulnerability to floods and droughts
. It positively affects the
chemical
and ecological status ofwater bodies
by restoring natural functioning of ecosystems and the
services they provide. The restored ecosystems contribute both to
climate change adaptation
andmitigation
.
Box1
