The Development of Managed Aquifer Recharge in Arizona

The growth in the use and application of managed aquifer recharge (MAR) in Arizona is an excellent example of progressive development of this technology for the improvement of the management of the limited water resources of a semi-arid region. It can be used as a guide for areas which are evaluating appropiate methodologies to improve the administration of their water supply and demand. In Arizona this development was realized in four phases. Phase 1 (1960s-1980s): EXPERIMENTAL STUDIES: Consisted of academic and institutional research and small scale testing at the University of Arizona and the U.S. Water Conservation Laboratory using both direct surface and well recharge. Phase 2 (1980s-1994): DEMONSTRATION PROJECTS: The need to store excess Colorado River (CAP) water when the Central Arizona Project Aqueduct was completed to Phoenix prompted a Salt River Valley recharge feasibility study (AMWUA) with several pilot tests. Concurrently some were also carried out in Tucson. Phase 3 (1994-2009): DEVELOPMENT OF LARGE CAPACITY WATER-SPREADING FACILITIES: The completion of the Granite Reef Underground Storage Project (GRUSP) with a permit capacity of 200,000 acre-feet/year started this phase and was followed by seven others each with a capacity of more than 50,000 acre-feet/year. Phase 4 (2009-.....): DESIGN, CONSTRUCTION AND OPERATION OF SMALL TO INTERMEDIATE CAPACITY MAR FACILITIES: In this phase projects with storage capacities of less than 20,000 acre-feet/year have and are being developed. They are predominantly for the storage of reclaimed water and are mostly owned and operated by municipalities. In the Phoenix area many of these facilities use vadose zone recharge well (VZRW) which were developed for use at the City of Scottsdale Water Campus facility. Aquifer replenishment and WQ improvement have resulted from this MAR program.