Page 184 - Water Loss Control

158 Cha pte r Ele v e n

A thorough discussion of customer meters is beyond the scope of this publication.
AWWA provides excellent guidance in several manuals that cover all aspects of sound
meter management. The M6 publication, Water Meters—Selection, Installation, Testing,
and Maintenance, provides comprehensive information on the basics of customer meter
2
management. The M22 publication, Sizing Water Service Lines and Meters, provides out-
standing guidance on customer demand profiling and sizing criteria, which are critical
for meter accuracy. 3
A word of caution about data handling: Meter accuracy is only the first step in
obtaining customer consumption data. While the meter must provide an accurate mea-
sure, the subsequent processes—including meter readings (gathered manually or auto-
matically), data transfer to billing systems, and archival operations—must also be
handled accurately, or the actual customer consumption will be distorted, with the data
from some customer accounts lost entirely. In many water utilities, it is not uncommon
to find accurate meter data transposed erroneously, adjusted improperly, or incorrectly
archived. If any part of the data path lacks integrity, it is easy to misinterpret apparent
losses solely as meter inaccuracy, with potentially costly consequences if loss control
decisions (such as replacing large numbers of accurate meters) are based upon this
faulty assumption.

11.4 Data Transfer and Systematic Data-Handling Errors
The customer water meter is only the beginning of a sometimes complicated trail that
ultimately generates a large amount of customer consumption data. Since most water
utilities manage data for many thousands of customers, systematic data-handling inac-
curacies can easily be masked by the shear volume of the bulk data. Figure 11.2 gives an
overview of the typical steps existing in the data trail from meter to historical archive.
In any of the above steps errors can be introduced into the output data that is ulti-
mately documented as customer consumption. Some of the ways in which the integrity
of customer consumption data may be compromised are

• Data transfer errors
• Manual meter-reading errors
• Automatic meter-reading equipment failure

1. Customer meter accurately registers water flow

2. Routine meter reading taken, manually or automatically

3. Meter readings are transferred to customer billing

4. Customer consumption is shown on water bill & archived

5. Aggregate consumption data summarized on reports
FIGURE 11.2 Metered consumption data archival path. (Source: Ref. 6.)