Measuring data uncertainty key to reducing non-revenue water

Posted 7 November 2016

non-revenue waterReducing non-revenue water is a major concern for all water utilities and one leading engineer says getting better at understanding data uncertainty is the key to interpreting water balances effectively.

GHD Principal Engineer Richard Savage, who will be presenting on water balances at the upcoming QWater in NSW Conference, said utilities will also be able to make better business decisions by determining water balances uncertainties, particularly those that are estimated and not measured.  

“Clearly, it makes perfect sense for any business to reduce components of its operation that come at a cost but don’t generate revenue. However, there is a point where you need to stop,” Savage said. 

“It’s not worth your while chasing non-revenue water if it’s going to cost you more than it’s worth to find it. Incorrect interpretation of the water balance can lead to continued investment in the reduction of non-revenue water, when in fact investment should reduce, or the opposite.

“If there are elements of the water balance that have wide bands of uncertainty, performance metrics will change substantially when you apply this uncertainty to the figures.”

Becoming better at estimating water balance unknowns helps lead decision-making in regard to the allocation of business resources, Savage said. 

“We need to go to the areas of our system where we have the least confidence in the measurements and find ways of improving the accuracy of those measurements – ways of improving our confidence in the measurements,” he said.

“The water balance itself, when it becomes fully populated, is a health indicator for the system. Utilities can use this indicator to drive where they are going to focus their resources to reduce non-revenue water.”

In order to become better at measuring uncertainty, Savage said placing more importance on meters in terms of asset management practice is a good first step to controlling measurement performance. 

“The simple thing for utilities to do is to go to those meter assets of which they have most direct control over – the bulk water meters,” he said.

“Utilities need to initiate programs of validation and calibration of their bulk flow meters. There are very few of them, but a small error on your big meter can make a very big difference on changing the arithmetic in your water balance.

“There is growing recognition within Australian utilities that these are really critical assets, but

if you asked a utility about their asset management systems, you’ll have to dig pretty deep before you find anything about meters.

“I’d like to see utilities elevate the criticality of all of their meters in their asset management system to the point where they have officers who are charged with primary responsibility for these assets to ensure performance of their fleet.” 

Savage said a secondary focus on metering and water balance efficiency is a barrier to building on the customer-first innovations that are so crucial to achieving business service delivery goals. 

“[Non-revenue water] is absolutely astounding to me. In every other manufacturing or retail business, you make damn sure the product that leaves your factory arrives at the customer,” he said. 

“In the water world, we have lived in this utopia of not really bothering too much. We are break-even businesses. If the books balance, generally there has been a view that ‘we are doing okay’.

“But with the rising emphasis on operating-costs reduction and customer service, there is now recognition that the component driving this is our meter. We are talking about mobile apps and smart information and real-time billing, and what do all of those things hinge on?

“They hinge on having confidence in the fact that the meter is accurately recording the volume of water going through it.”

To hear more from Richard Savage about achieving healthier water balances, register for the QWater in NSW Conference, held from November 24-25.