Smart water metering for a dry continent

Australia is the second driest continent in the world after Antarctica, but it is one of the highest per capita water consumers. Growing urban populations, economic growth and increased agricultural production are all expected to increase water usage further in the coming decades.

According to Future Directions International in its 2014 report on Australian water security¹:

“As Australia’s population continues to grow, the demand for urban water will create challenges for water managers. The majority of natural water resources in Australia have already reached allocation limits. In some instances, resources are over-allocated between user groups and economic mechanisms have been adopted to manage usage. Meeting competing water demand into the future will require innovation, the economic valuation of water and co-operation across sectors.”

The Millennium Drought in 2002 raised awareness of water scarcity in Australia and had a significant effect on water management policy as it highlighted the vulnerability of Australia to fluctuations in rainfall patterns. This resulted in falls in household water consumption of 28% between 2004 and 2010; but as Australia’s population continues to grow, the growing demand for urban water will be a challenge.

The Bureau of Meteorology (BOM) is currently reporting both a strong El Niño in the Pacific (expected to continue into the first quarter of 2016) and a positive Indian Ocean Dipole (IOD), with both indices being above +1°C. El Niño is usually associated with below-average rainfall in eastern Australia, while a positive IOD reinforces it. Currently, water catchments are very low and soil moisture levels are significantly below average, with agribusinesses in various parts of Australia being severely impacted. These types of conditions are expected to become more frequent in the future with the growing effects of global warming.

Usage patterns and forecasts

The two largest areas of water consumption in Australia are agribusiness and domestic urban use.

Agribusiness is the largest single consumer of water in Australia, with the ABS reporting that in 2012–13 the industry consumed 11,900 GL. Since surface water resources have in most cases exceeded allocation limits, further agricultural expansion will require investment in alternative water sources, such as on-farm recycling and the expansion of water capture and storage facilities.

The domestic household use of water was 14% of the total in 2009–10 (ABS) and 63% of urban water consumption. With the population expected to rise to between 36.8 and 48.3 million by 2061, the rise in urban water demand presents a significant challenge, and a long-term management plan is necessary.

“Climate change forecasts suggest that natural water systems will become increasingly unreliable,” said Future Directions International.² “Much of southern Australia, where key agricultural areas are located, has been identified as particularly vulnerable to climate change… Australia will require greater volumes of water and more advanced infrastructure to meet user demand into the future. It also needs to become a more efficient water user.”

Getting more efficient means better measurement

While additional water sources may need to be explored to assist with future demand, better utilisation of current resources is something that needs to be acted on. But, of course, better utilisation requires a better understanding of actual usage and demand, and, historically, the available water metering technologies have not been adequate to fill this need.

One important area in which better water monitoring would be of assistance is in the area of leak detection. Whether it is leakage within end-user properties or leakage in the distribution network, leaks account for a significant waste of Australia’s scarce water resources. In 2014, Western Australia’s Auditor-General found that the WA Water Corporation was losing billions of litres of water³:

“In his report… Colin Murphy found the government agency was losing about 30 billion litres of water each year — ten billion more than what is considered acceptable,” wrote ABC News reporter Stephanie Dalzell.

“‘They need to be doing more to pursue loss, they do have a leak detection program which is a good thing, that’s actually found and saved us 3.4 billion litres over the past three years,’ he [Murphy] said.”

The interesting thing about this quote is that it implies that 20 billion litres of water loss is acceptable, and that 3.4 billion saved was a good result. The same article explained that the Water Corporation in 2012–13 supplied over 357 billion litres of drinking water across WA, but that 13 billion litres of consumed water was not billed for. There certainly appears to be a strong case for better water metering in WA.

Similarly in Sydney, a recent ABC report⁴ of a burst water main in the inner-west suburb of Dulwich Hill revealed that Sydney Water maintains 21,000 km of water pipes and 25,000 km of wastewater pipes, but that more than 50% of the pipes are more than 70 years old, and that a significant proportion is reaching end-of-life. Severe leaks can occur without warning, and minor leaks go undetected or unrepaired for long periods.

Smart water meters

Currently, there are three types of water meters in use for residential and many commercial water usage measurements: accumulation meters, pulse meters and interval meters. Accumulation meters simply total the continuous water consumption and therefore only give an accumulation figure when read — typically once every three months. Pulse meters record a timestamp each time a certain volume is consumed, while interval meters record consumption over regular fixed intervals (eg, 15 or 30 min).

To date, while all three types can be found, they are still only generally used to measure quarterly consumption, since the infrastructure necessary to take advantage of interval meters is not generally in place — these meters have, to date, only been used for billing purposes. Once the infrastructure is in place, however, interval meters will make it possible for water authorities to obtain detailed information on when customers are using water, allow analysis of network leakage, and make water network analysis and forecasting more possible.

Of course industry makes use of industrial flowmeters that can provide highly accurate flow rate and volume data continuously, and which are fully adaptable to a digital data network — but the cost of implementing them at every end node on a water network would be cost-prohibitive.

The rollout of smart metering capabilities, using network-capable interval meters, can be seen as a similar endeavour to the rollout of smart electricity metering and can take advantage of much of the same technology. Since the rollout of smart electricity metering is already in an advanced stage in many places, there may be the opportunity for water authorities to take advantage of shared infrastructure.

Benefits of smart metering

Smart water metering will do more than allow for automated meter reading. It is expected to gather more granular water usage data (multiple daily readings), provide two-way communication between the meter and the water authority, and provide usage information for the customer via a low-power wireless network such as ZigBee — allowing the consumer to make more informed water usage choices.

From the perspective of the water authorities, there are a number of benefits to be gained from smart metering, backed up by suitable big data analytics. Significant benefits could be found in:

• Improved urban water planning. Having a better understanding of residential, commercial and industrial water consumption patterns will help urban water planners to better understand consumption trends.
• Improved demand management. The use of data analytics from smart metering could significantly improve decision-making in relation to water demand management strategies, particularly during drought conditions or other events, and when planning system upgrades or maintenance.
• Evidence-based forecasting. Water consumption data will also allow water authorities to monitor the effect of scarcity pricing or water restrictions in near-real time.
• Proactive leakage management. Water utilities would be better able to intervene when infrastructure leakage events occur.
• Targeted demand efficiency. Monitoring end-user consumption provides the ability to quantify the effect of targeted water efficiency programs — such as efficiency rebate offers — or of changes to tariff systems and their effect on end-user behaviour.

From the end-consumer perspective, smart metering also offers benefits. According to Associate Professor Rodney Stewart of Griffith University⁵:

“The present customer water information and billing arrangements are vastly inadequate. A smart metering system provides the impetus for a new approach to knowledge transfer of water consumption data, directly to consumers via a range of communication platforms and in-house displays.”

In the same way it is envisaged for smart electricity metering, the use of smart water metering should lead to a more informed consumer, who can then make better choices about their water usage.

Challenges

While deploying smart meters will provide data to support all these benefits, it is not sufficient in itself. Water utilities often do not have robust data acquisition and informatics algorithms and tools in place. By itself, big data without effective and efficient data mining methods and algorithms to achieve enhanced decision-making is not useful.

“City-wide smart metering implementations have the potential to stream gigabytes of time-stamped water use and other associated information (such as water temperature, pressure, quality) from pipe networks right down to the individual water use appliances (eg, washing machine) and fixtures (eg, tap),” said Professor Stewart. “Such datasets are powerful for a range of water planning, engineering and customer response decisions — but only if processed, refined and reported in a way that is more intuitive and informative than traditional approaches.”⁶

The main challenges therefore are:

• Smart meter rollout.
• Network infrastructure to support smart meters.
• Providing smart meter data to consumers at little or no additional cost (enhanced service).
• Developing the big data analytics that will be needed to take advantage of smart meter data.

While all these are solvable, they come down to two more basic issues: cost and data volume. Firstly, smart meters themselves are more costly than interval meters, and a smart meter rollout will mean replacing meters well before their end-of-life.

Cost aside, smart meters are of little benefit without the critical cloud or edge-based software systems that make collected data useful — both for water authorities and consumers. Water utilities often do not have the in-house capabilities to build large-scale data acquisition and processing algorithms and tools. Big data alone without effective data mining methods tends to bog down water utility operations as they drown in data.

Conclusion

While Australia is the driest populated continent on Earth, growing urban populations, economic growth and increased agricultural production are all expected to increase water usage further in the coming decades. Additional water sources may be needed, but better utilisation of current resources, and the reduction of water wastage, are goals that can be achieved with the application of modern data acquisition and data mining technologies.

References

1. Lehane S 2014, Australia’s Water Security Part 2: Water Use, Strategic Analysis Paper, Future Directions International.
2. Ibid.
3. Dalzell S 2014, Billions of litres of water lost each year through ageing network: report, <http://www.abc.net.au/news/2014-02-19/wa27s-water-loss-in-billions-of-litres-says-ag/5270660>, ABC News.
4. ABC News 2015, City's water pipes still in good condition despite burst main flooding Dulwich Hill homes, Sydney Water says, <http://www.abc.net.au/news/2015-09-29/dulwich-hill-water-pipes-still-in-good-condition-despite-age/6813880>, ABC News.
5. Stewart R 2015, Smart water metering: saving water and money, <http://app.griffith.edu.au/sciencesimpact/smart-water-metering/>, Griffith University.
6. Ibid.

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