Unsustainable groundwater consumption represents a reliance on environmental credit. A reduction in groundwater credit availability, by policy or physical constraint, can create an environmental credit crunch homologous to a financial credit crunch. This paper presents a logical argument for a systemic, structural isomorphology between groundwater credit and financial credit in a contractionary environment. Monetary policy can be used to contract credit and control the aggregate demand of an economy. As society transitions to sustainable groundwater management, similar policies may be required to facilitate a contraction of groundwater credit. The analysis presented may justify the application of knowledge about monetary policy to groundwater management policy. A comparison of the structural components of each system is presented along with a description of the causal loops of the systems. The assertion of isomorphic structures is further supported by a logical explanation of the mechanisms of systemic interaction between components of each system. This analysis can assist technical managers tasked with groundwater management to better understand this complex technical system.