Comment on “The persistence of the water budget myth and its relationship to sustainability” by J.F. Devlin and M. Sophocleous, Hydrogeology Journal (2005) 13:549–554

Abstract

Devlin and Sophocleous (2005) have written a thoughtful and provocative article on the subject of sustainable pumping and sustainable groundwater-resources development. In the subject article, sustainable pumping was defined as “a pumping rate that can be maintained indefinitely without dewatering an aquifer”. Sustainable groundwater-resources development is, according to the subject article, a broader concept that encompasses groundwater use and its environmental and human repercussions. Devlin and Sophocleous (2005) contend that the definitions of sustainable pumping and sustainable groundwater-resources development have been confused by some in the groundwater community, and, that the confusion has led to the “water budget myth” (see also Bredehoeft 2002). The water budget myth is—according to Devlin and Sophocleous (2005)—the “idea that sustainable pumping must not exceed the recharge rate in a given aquifer”. A substantial portion of the subject article is devoted to proving that the water budget myth is conceptually flawed. This commentary presents an alternative interpretation of the relation between sustainable pumping and sustainable groundwater-resources development to that advocated by Devlin and Sophocleous (2005). This alternative interpretation renders superfluous the distinction between sustainable pumping and sustainable groundwater-resources and, as corollary, makes the water budget myth an innocuous—if not laudable—concept. In addition, this commentary argues that sustainable pumping, as defined in the subject article, has very limited practical applicability in the context of groundwater extraction under variable climate. This commentary argues that sustainable pumping must be adaptive and take into account climate fluctuations, especially protracted drought.