Estimation and quantification of injection well clogging, Tucson, Arizona

Abstract

In 1993, the City of Tucson began artificially recharging Colorado River water into local aquifers for storage. Pilot recharge tests in 1989-90 were done to assess how the clogging of injection wells would affect recharge operations. Data from the pilot recharge tests were used to develop a correlation between the clogging potential of the recharge water (as measured by the modified fouling index (MFI)), which was ground water, clogging rates and the hydraulic conductivity of the aquifers. This correlation was used to estimate clogging rates using Colorado River water. Results of my study show that the clogging potential of Colorado River water is nearly 10 times greater than that of ground water. This is due mainly to differences in water chemistry. This study further develops the correlation developed by the pilot recharge tests. This correlation provides a tool that can be used for other recharge projects to evaluate potential clogging rates, sustainable injection rates, and redevelopment frequencies.