Calibration of metering required for utility water main leak detection

One of the most overlooked sources of "new water" is that which we already put into our water mains, yet which simply leaks away.  Water mains are the oldest municipal infrastructures and

• Per the American Water Works Association (AWWA) "The range of water losses for the 21 utilities answering the survey was 6.8 – 45.5%, with an average loss of 22.6%.   The real losses given in gallons / mile of main / day are 645.42 – 3,496.21, with an average of 1,821.15 gallons / mile of main / day." and
• Per the American Society of Civil Engineers (ASCE) 2020 report, the US drinking water infrastructure only get a near failing grade of "D"; and
• The recent 2018 Utah State University study "Water Main Breaks in the US and Canada: A Comprehensive Study" revealed that the water main breaks in the preceding 6 years were up 27%, with the slope of the rate of failures increasing.

Assuming a leakage rate of, say, ~20%, said leakage is more than all planned sources of other "new waters" from recycling and desalination.  Moreover, why should such expensive new sources of water be delivered by water mains that continue to leak.

A leak is by definition the loss of mass or (standard) volume from a supposedly closed system.   The reason that leaks go undetected by water utilities -- sometimes for decades -- is their inability to provide accurate measurement with low uncertainty.  And this is due to the fact that virtually no utilities have low uncertainty large water flow calibration facilities.   Low uncertainty calibration of metering systems would lead not only to quick detection of sudden large losses, but also to detection of lower level losses on a longer term cumulative basis.

Noting that calibration of measurement systems is a mandated legal requirement for all quality management systems , we would simply note that water utilities thus do not have rigorously based quality management systems.  Thus, water main leakages frequently persist for years -- sometimes even decades -- without detection, rather than being detected at low levels that are more easily remediated/repaired.  Until metering systems are accurately calibrated with low uncertainty, repairs are performed only on a haphazard basis as they appear on the surface -- or result in sudden catastrophic failures disrupting supply of water from sections of a city.

Dr. Arnold Liu

QUANTUM DYNAMICS, INC. 

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Taxonomy

• Policy
• Technology
• Research
• Water Supply
• Infrastructure
• Leakage Reduction
• Meters
• Measurement
• Utility Management
• Water Balances
• Advanced Metering Infrastructure
• Distribution Network Management
• Water Loss Control
• Critical Infrastructure Protection
• Leak Detection and Inspection