MEASURING WATER USE IN A GREEN ECONOMY - UNEP

Measuring water use in a green economy
it is possible to develop them so that they
become the primary source of information
used to document how, where and when
water may be and is used.
• Systems built in this manner typically
begin by partitioning a water resource into
a number of ‘pools’ of differing allocation
priorities. Entitlements to access water
allocated to each pool are then distributed
amongst users or user groups. As the
volume of water within the pools is likely
to change from season to season, each
entitlement is defined as a share of any
water allocated to the pool. Sustainable
diversion limits are set for each pool in
a manner that ensures enough water is
set aside for conveyance, maintaining the
environment and meeting other needs.
• The water for maintaining the environment
will ensure that ecosystem services are
delivered as an indirect benefit of water
use, in addition to its use by agriculture,
industry and human settlements.
• Water accounting is crucial to allow
those responsible for water registers
to undertake this prioritisation. Without
adequate data and sources of information
on water availability, use and productivity,
these decisions cannot be made on a
rational basis.
• In more and more parts of the world that
are increasingly water stressed, water
accounting has therefore become a key
statistical activity for governments, similar
to accounting for the carbon intensity of
GDP. Together with investments in green
sectors, these indicators are becoming the
starting point for managing the transition
to a green economy.
• However, a current shortcoming of
traditional water accounting (UNSD,
2007) is the lack of direct consideration of
environmental impacts and, often due to
data restrictions, the lack of disaggregation
to more meaningful hydrological units and
temporal information. Further national
efforts are needed to generate such data,
while on the international level further
work is needed on the revision of SEEA-W
to fully integrate ecosystem services and
natural capital into accounts.
• An integrated approach to water
management across media and sectors
is needed, as there are potential trade-offs
between land and water use, ecosystems,
GHG emissions, soil degradation, etc.
• Water scarcity indicators provide an
overview and guidance at the pan-regional
level and can be used to inform the
international coherence of more detailed
regional or local assessments, but by
themselves do not provide detailed enough
information to guide policy decisions.
• A life cycle perspective is needed in order
to account for water use and its related
impacts along the entire production chain,
from feedstock production to conversion
and final use of both agricultural and
industrial products. While it is important to
take a holistic approach and a long-term
perspective, cooperation needs to occur at
the river-basin level.
• It has become clear that there are basic
philosophical differences between existing
accounting methods for water use over
the life cycle of products and systems.
The Water Footprint Network (WFN)
— and with it the virtual water concept —
understands water as a global resource.
According to this approach water is limited
only at the global level. Allocating more
water to an industrial product means less
water going to food, the environment or
other uses. Therefore water volumes are
the main concern. For a meaningful waterefficiency
assessment, providing tools for
regional and local water management,
the Water Footprint Assessment needs to
specify the seasonal and spatial aspect
of the analysis more clearly. Furthermore
additional criteria must be developed to
assess economic and social sustainability
and assess the possible opportunity costs
of different possible water uses.
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