By Rich Anderson
September 25, 2006

Pam Malone, Vice President for Itron, Inc., and Wayne Morgan, Vice President for American Water, presented information at the Mayors Water Summit in Santa Barbara about how cities can detect leaky pipes and conserve water through the application of commercially available technology. Morgan stated that the current combination of limited water supplies and costly infrastructure should drive cities to invest in conservation planning tools. He pointed out that water meters are the “Cash Register” for water providers. Cities that employ water meters can account for the water distributed from the municipal treatment plant to the end-user (the homeowner, office, restaurant, etc.).

Morgan said that automated meter reading (also know as AMR) combines computer technology capabilities to bring greater efficiency to the water production and use cycle. Meters are fitted with radio frequency transmission equipment to transmit consumption data. Itron is a national leader in deploying smart AMR systems throughout the nation. Teaming with American Water to deploy AMR in the water distribution systems that they operate is a good way to modernize drinking water infrastructure.

An AMR system can transmit water consumption data to a handheld receiving device or with a mobile device. The mobile receiver offers the greatest efficiencies because of speed and minimization of manpower. Morgan states that it is the lowest cost alternative for monthly, weekly and sometimes daily reads. Installation of basic AMR also prepositions the system for advanced AMR technology to piggyback onto existing systems also called “Fixed-Network Systems.”

AMR is often the preferred technology of cities because it enables customer-billing systems to achieve greater accuracy. Now more than ever, cities are compelled to move towards full-cost accounting to afford operating and maintaining water treatment and distribution systems. Cities that do not use any metering are hard pressed to raise the funds necessary to rehab or expand water system infrastructure. Cities that use standard metering are somewhat more able to afford rehab and/or expansion. Cities that use AMR are best equipped to match system revenues and costs; and are in a better position to conserve water as well.

Malone commented on the growing need for cities to account for water consumption and to find and fix leaking pipes to conserve water and preserve revenues. She stated that unaccounted for water (UAW) that is lost somewhere between the treatment plant and the water consumer could be as high a 20 percent nationally. Malone cited the Mayors Water Council 2005 National City Water Survey that reported 35 percent of cities may face critical water shortages in the next 20 years. Because the value of water has increased the importance of finding and fixing leaks has increased.

Malone described the old state-of-the-art water loss detection approaches as primitive and labor intensive. Essentially, according to Malone, the old method was to wait to see an obvious water leak or conduct a “listening” survey where various segments of underground pipes are physically examined by ear.

The new state-of-the-art involves a more sophisticated acoustic monitoring technology. An acoustic device is connected directly to a pipe and can detect leaks via sounds (vibrations) traveling through the pipes. Leak noise exhibits certain characteristics with propagation and frequency signatures that can be interpreted to be pipe breaks. The acoustic device filters the signatures and can amplify them for better analysis. Software is then used to identify patterns that allow them to be fit into categories. One such software capability is named the MLOG System. This system can translate noise into color maps that help managers pinpoint leaks. Malone stated that the acoustic translations not only help pinpoint leaks, but they significantly decrease the manpower required to field check the leak point. Malone said that the MLOG System can be coupled with an advanced AMR system to yield multiple benefits of full-cost accounting, near perfect customer billing and sophisticated, low-cost leak detection to reduce UAW. Currently, the combined AMR and MLOG systems are being field tested in Irvington (NJ).