Designing tradeable rights to manage aquifer recharge according to robust separation principles

[Departement_IRSTEA]RE [TR1_IRSTEA]GES / USAGES

International audience

English. Many cities are experiencing mature urban water economies, characterised by limited opportunities for future water impoundments, rising incremental supply and infrastructure costs, intensified competition and increased interdependencies between diverse water uses. Aquifer storage and retrieval (ASR) is currently promoted as one option to augment existing supplies and in many jurisdictions is assuming increasing importance in the portfolio of urban water management strategies. Consistent with trends in international water policy development, Australian water reform has emphasised institutional and governance approaches promoting voluntary transfers of water through market exchange. The reform process has made substantial advances in addressing the constraints and tensions associated with mature rural water economies, with limited influence in urban water systems. What remains unclear is the degree of alignment of new water management technologies such as ASR operations with explicit water reform directives of market development and the capacity of subsequent urban water legislation to provide consistent and coherent ASR guidelines. The paper describes a systematic approach to align the hydrological characteristics of an aquifer with economic and policy interpretations central to the development and management of ASR. The paper introduces a schema to identify the elements of the urban terrestrial water cycle specific to ASR, the development of a typology to characterise the aquifer potential for ASR, and identify and determine the nature of property rights for each system element according to the principles of robust separation of water rights.