Page 194 - Water Loss Control

168 Cha pte r Ele v e n

In following with the above recommendations, the CWC manager determines to launch
a revenue protection program that will analyze the customer billing process and insti-
tute annual customer meter accuracy testing.
The billing process analysis (flowcharting) is envisioned as a 2-month project cost-
ing $24,024. This cost includes the analysis and any low-cost apparent loss corrections
that can be immediately incorporated into the process. CWC conducted accuracy test-
ing of a sample of customer meters during the compilation of its initial water audit and
determines to continue testing a sample on an annual basis in order to track the accu-
racy of the customer meter population and monitor degradation of accuracy over time.
The projected cost of this effort is $7,140 to test 50 residential meters and 5 large meters.
The total first-year cost of the two component revenue protection program is estimated
at $24,024 + $7,140 = $31,164. By applying its composite customer retail billing rate of
$3,945/million gal, CWC need only recoup 7.90 million gal of apparent loss to break
even during the first year of program operation. This is only 3.8% of the total apparent
loss volume of 208.22 million gal quantified in the water audit. If each residential cus-
tomer consumes 800 cubic feet/month of water (71,808 gal/year), then the equivalent
of recovering 110 missing accounts from the billing roles would meet the cost-effective
breakpoint of 7.90 million gal recovered. This is less than 1% of the total of 12,196
accounts in the customer billing system. It is evident that recovering losses valued at
the customer retail rate offers a swift and high payback.
During the early phases of a revenue protection program, significant recoveries
may be recouped with less costly programming and procedural refinements. However,
as the program matures, the water utility will ultimately consider more extensive and
costly improvements to control apparent losses. Such efforts can include wholesale
meter change-out, installation of automatic meter reading (AMR) systems, or imple-
mentation of a new computerized billing system. The economics of such long-term
improvements should be carefully considered, but with a mature program, sufficient
data will exist to provide a basis for rational decision making.

11.9 Apparent Loss Control: A Summary
Apparent losses distort the measure of the volume of customer water consumption and
cause water utilities a loss of revenue. Controlling apparent losses, however, can be
very cost-effective since initial corrections may require relatively little work with poten-
tially high payback. It is often advantageous to target apparent loss control early in the
water loss control program in order to quickly generate recoveries that can seed further
water loss reduction activities, particularly real loss reduction. Loss control in almost
any endeavor is an effort of diminishing returns, but it is likely that many water utilities
have significant apparent losses which can be cost-effectively recovered to enhance the
utility’s revenue stream and further promote the water loss control program.

References
1. Environment Canada. “Metering.,” The Management of Water. [Online]. Available:
www.ec.gc.ca/water/en/manage/effic/e_meter.htm.
2. American Water Works Association. “Water Meters—Selection, Installation,
Testing, and Maintenance.” Manual of Water Supply Practices M6: AWWA, 1999.
ISBN 0-58321-017-2