This paper describes the metering program that Southern California Water Company has developed. Their desire for a rational and consistent method for maintaining their large water meters and to provide more accurate billings has led them to the development of a computerized decision system to produce the most economical maintenance schedule for their meters. The computerized decision system and a notebook computer allows field technicians to properly maintain the water meters based on the current account information. This paper discusses the computer program, databases, data entry, consumptive use tests (CUT), field tests, and implementation based on grant monies.