Back to Publications

Conjunctive Management of Hydrologically Connected Surface Water and Ground Water: The Problem of Sustainable Use

Douglas L. Grant, Proceedings of 54th Annual Rocky Mountain Mineral Law Institute (2008)

Thirty-five years ago, the National Water Commission reported that Arizona, Colorado, and New Mexico were grappling with heavy ground water use that reduced stream flows and interfered with much earlier surface water appropriations.1 The problem has now spread to other western states. It has also broadened beyond the initial focus on interference with earlier appropriations to include environmental concerns about interference with instream flow values not always protected by formal water rights and impairment of ecosystems dependent on high ground water levels. Meanwhile, Arizona, Colorado, and New Mexico have continued to grapple with the problem and change their approaches.
The core of the problem is the use or desired use of hydrologically connected surface water and ground water to fill formal water rights and provide instream flow and ecosystem benefits in amounts that exceed perennial supplies. Addressing the problem has proactive and reactive elements. Where existing water uses do not yet exceed perennial supplies, the proactive goal is to prevent uses from expanding until they outstrip supplies. Where existing water uses already exceed perennial supplies, the reactive goal is to find some way to bring uses and supplies into a sustainable balance with minimum pain.
This chapter will survey the legal techniques that different states are employing to pursue these g