leaks on water mains and at device connections or by tank overflows. These losses are costly for the utility because, like apparent
losses, they are not metered. In addition, finding these leaks can
help utilities conserve water and meet regulatory requirements.
Technology to find water losses varies but collecting data
from sensors or monitoring points located throughout the distribution system improves the efficacy of AMI solutions. For
example, acoustic leak detection can operate on AMI networks, listening for the noise created by leaks in pipes and
sending data from devices on water mains back to utilities
where it is correlated to identify leak locations.
The Aclara STAR® ZoneScan solution, as an example, combines acoustic data loggers from Gutermann International with
Aclara’s STAR network technology to provide fully integrated
leak detection through the fixed-network AMI system.
The loggers gather time-synchronized sound recordings
that are sent back to the utility over the fixed-network infrastructure. Web-based application software correlates the
data between loggers and provides visual identification of
high-probability leak locations. Similarly, other types of sensors
monitor other trouble spots on the distribution network such
as changes in pressure or tank overflows.
By adding analytics and finding additional ways to employ
their AMI networks, water utilities are building a far more advanced and encompassing smart infrastructure solution (SIS)
for managing their water distribution systems.
The versatility of this SIS approach provides greater network visibility, manageability and actionable information for
utilities and their customers. By integrating a range of hardware, software and data technologies, SIS helps water utilities
reclaim lost revenue and mitigate the impact of theft, unmetered consumption, meter inaccuracy and leakage. WW
About the Author: David Rubin is a product manager with Aclara, provider of smart
infrastructure solutions (SIS), metering, monitoring, communications and customer
engagement solutions to water, gas and electric utilities.
the process was time-consuming and some homeowners
would not be notified until a month or more after the leak
started. Bend recently started using software to analyze consumption patterns, allowing Cashwell to do a similar review
daily rather than monthly.
DRILLING DEEP WITH ANALYTICS
In addition to identifying leaks for customers, analytics can
help solve other problems for water utilities. One of the thorniest is identifying and reducing apparent water losses that occur
because of meter tampering, billing errors, and failing or improperly sized meters. Apparent losses are particularly tough for
utilities to identify because they are not physical water losses but
rather water that is metered but unbilled, which means these
losses directly affect revenue collection and the bottom line.
One of Aclara’s partners, Valor Water Analytics, has developed
a set of water-specific algorithms that can help utilities recover between one and five percent of top line revenue that is now being
lost in their systems through apparent losses. For a $100 million
utility, that amounts to one to five million dollars a year.
These algorithms are especially useful in identifying dying
or decaying meters, which normally cannot be found without pulling meters out of the ground and testing them. In
fact, most utilities do not look for failing meters. They change
them out during routine meter replacement programs, which
are expensive for the utility because many good meters are
replaced along with the bad.
To identify failing meters, the apparent water loss detection
software analyzes historic AMI data and then ongoing hourly
water-use data. This establishes a baseline for each meter, after which irregularities from the pattern are identified through
proprietary algorithms and ongoing analyses.
Meters that show a pattern of decline can be replaced individually. This more surgical approach to pinpoint bad or incorrectly sized meters can help utilities reduce apparent losses
and find hidden revenue.
REDUCING REAL WATER LOSSES
Real water losses on the distribution system are caused by
Illustrated is a classic fill-valve leak with a continuous flow of 1 ft3/hr.
These leaks can be isolated by looking at data sent during the night.
Utilities can identify poorly performing meters and take a surgical approach to replacement.