This third edition of M22 contains information needed to estimate customer demand and maximum expected flow that can be used to size new service lines and meters. This edition expands the ways to approach the sizing of water service lines and meters and offers improved methods for the sizing of dedicated irrigation meters. M22 includes a useful field method called demand profiling that can be used to evaluate actual customer use patterns and help optimize meter size selection.

The data presented in M22 were obtained from field measurements, utility surveys, technical publications, and hydraulic design calculations. This manual emphasizes that utilities having more information about a specific sizing situation will result in the best sizing decision from the tap to the meter. This information has been condensed into a simplified format to assist readers in addressing most common service conditions. The methods contained in this manual are appropriate for water utility managers, engineers, planners, technicians, field operations personnel, and consultants involved with designing and constructing projects requiring water service.

This utility operations manual will guide the utility in choosing the best sizes for customer water meters and service lines.

Historically, water utilities sized customer service connections and meters based upon the peak flow rates that the meter was expected to encounter. Since peak flows occur only rarely, meters sized in this way record the lower, average daily flow in the low end of their design range.

Unfortunately, many meter types are less accurate in the low end of their flow range with very low flows not captured at all. This results in lost legitimate revenue for the utility.

Many water utilities have recovered considerable water and revenue by right-sizing oversized customer meters. Right-sized water meters, because they more accurately record water consumption, can increase utility revenue, as well as reduce the amount of apparent water loss in the distribution system.

Properly sized service lines and meters provides many benefits for both the customer and the utility:

– Accurate measurements of water use, flow, and demand

– Less under-billing of customers, which increases utility revenue

– Optimum cost of service

– Reduced equipment maintenance

– Fewer customer complaints

– Reliable water-use data for better demand forecasting, improved hydraulic modeling, and enhanced water conservation planning

Topics include estimating consumer water flows, peak water demands, demand profiling, metering equipment, and procedures for calculating service lines and meters for optimum water revenue and lowest service cost. Includes numerous tables and sample calculations.