This publication presents field observations on the changes in the plant and animal communities during the first 5 years of operation of the Leaky Acres Recharge Facility, Fresno, Calif. The nature and magnitude of ecological changes were recorded as the aquatic environment was generated and stabilized. The impact of these changes on recharge and surrounding urban area is discussed. These observations have suggested various prerecharge surveys needed in preparing an environmental impact report for a basin-type, ground-water recharge facility in an urban environment.