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Title: HESS Opinions: How should a future water census address consumptive use? (And where can we substitute withdrawal data while we wait?)

Abstract. Despite the centrality of the water balance equation to hydrology and waterresources, in 2018 we still lack adequate empirical observations ofconsumptive use of water by humans and their economy. It is therefore worthconsidering what we can do with the withdrawal-based water use data wealready possess, and what future water census measurements would be requiredto more accurately quantify consumptive use for the most common mesoscale usecases. The limitations of the currently applied simple net consumptive use(SNCU) assumptions are discussed for several common use cases. Fortunately,several applied water management, economics, and policy questions can besufficiently addressed using currently available withdrawal numbers in placeof water consumption numbers. This discussion clarifies the broadrequirements for an improved “stock and flow” census-scale data model forconsumptive water use. While we are waiting for the eventual arrival of amore sophisticated water census, the withdrawal data we already possess aresufficient for some of our most important scientific and applied purposes.

Authors:
Award ID(s):
1639529
Publication Date:
NSF-PAR ID:
10105102
Journal Name:
Hydrology and Earth System Sciences
Volume:
22
Issue:
10
Page Range or eLocation-ID:
5551 to 5558
ISSN:
1607-7938
Sponsoring Org:
National Science Foundation
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