Smart water: a brief history

The smart water metering market emerged in the 2000s as water utilities responded to global trends of using detailed and near real time data and analytics to deliver more predictive and proactive services. The backbone of this effort is advanced metering infrastructure (AMI) technology. AMI can provide a remote and constant two-way data link between utilities, meters and consumers. Communications are delivered through various technologies including power line communications (PLC), telephony, broadband, fibre optic cable, wireless radio frequency and cellular transmissions.

Through a communications infrastructure of concentrators, repeaters and gateways, data is passed between meter and utility and funnelled into analytical software that can immediately set off pre-determined alerts. This is as well as produce accurate billings and consumption patterns at neighbourhood and area levels, inform other utility software such as GIS (Geographic Information Systems) and SCADA (Supervisory Control and Data Acquisition) and departments including customer services, pumping stations and reservoirs. Apart from monitoring the current status of water consumption, data can contribute towards hydraulic modelling to help predict outcomes and changes in water distribution.

Hydraulic modelling and network monitoring can be used by utilities to make evidence-based network investments and upgrades. Utilities can also send information back to the meter to perform remote upgrades and fixes, reset alert parameters, shut off water supply during change of tenancy or reduce water flow for unpaid accounts.

AMI vs. AMR

Smart water metering, however, does not come without a set of questions, uncertainties or debates. Four of the largest industry debates centre on technology, operations, communications and the marketplace.

Water utilities often debate whether to fully convert to AMI or run an AMR (automatic meter reading) water grid instead. The truest of smart water grid definitions requires AMI technology and its enabling two-way communications. Many water utilities, however, do not see a clear advantage to AMI and feel the "smart-lite", uni-directional communications from meter to utility offered by AMR is fit for purpose.

Receiving one-way information for accurate billing, leakage and NRW detection and GIS and SCADA is viewed as solving the bulk of water utility needs. Many water utilities feel the financial cost to roll out and operate an AMI grid will not justify the benefits of two-way communications. It is felt that remote upgrades rather than replacements will be infrequent, centralised alarms will be sufficient and utilities will rarely restrict water flows into homes, even if this is legally permitted.

This issue needs to be addressed on a case by case basis, but water utilities, widely known to be risk-averse, will find the most "future-proofed" investment in AMI deployments. An example of which is the UK's most advanced project currently being deployed by Thames Water in London. AMI offers the most advanced capabilities and as this technology evolves and utilities grow more sophisticated in their data analysis and operations, AMR deployments may prove limiting; water utilities stand to gain the most through AMI.

Smart water metering differs from smart energy metering in that smart water meters are rarely in convenient reach of mains power supply. As a result smart water meters are dependent on a reliable and long-lasting battery to power data transmission. Ensuring a 15 year battery life, which matches the lifespan of most meters, is essential for investments. Because of the proximity to water and possible submersion of meters, batteries are sealed water-tight and are not meant to be replaced.

Operating an AMR deployment with scheduled data transmissions does not impinge on this 15 year battery life. Deploying an AMI system, however, where meters must be constantly ready to receive incoming transmissions can drain battery life significantly, down to eight years or less. This has a large impact on the business case for investment. The market is seeing solutions to this challenge where meters will power up to potentially receive transmissions on scheduled intervals (one minute, five minutes etc) rather than a constant state of readiness. This ensures maximised battery life and offers the benefits of a two-way AMR-like communications system.