The primary source of revenue for the Alameda County Water District is through the water consumption of residential customers who have 5/8” or 3/4” water meters. These meters make up about 90% of all District meters and generate about half of all consumption revenues. Economical operation of these meters is therefore an integral part of the District’s effort to provide high quality water at reasonable costs.
Since water meters are mechanical devices, their accuracy decreases over time which means a corresponding loss of potential revenue. To gain additional accuracy, however, would mean replacing the meters at additional cost.
How old does a meter have to be before it makes economical sense to replace it? To answer this question, the District used statistical sampling methods to determine meter accuracies over time. An economical analysis was then performed to determine an optimal replacement age. Together with operational factors, the optimum age at which to replace plastic meters in the District was found to be approximately 15 years old.