Metering and Submetering

A water meter is a device used to measure the amount of water consumed. The Alliance for Water Efficiency supports full metering of all urban water customers. Installing meters and billing according to usage is the single most effective water conservation measure a water utility can initiate. While many water purveyors are fully metered, there are a surprisingly large number of water providers with unmetered residential customers -- still charging customers flat rates -- even in water scarce regions of North America. As measured recently by utilities who have installed meters, unmetered water consumption can be reduced 15% to 30% when metering and commodity rates are implemented.

A working group of water utilities, with the assistance of funding from the California Department of Water Resources, has engaged Don Schlenger and Associates, LLC  to prepare a template Request for Proposals (RFP) of Automatic Meter Reading (AMR) and Advanced Metering Infrastructure (AMI) specifications regarding aspects of transmitted meter data and the formats that it may take. The highest priority in the effort is the advent of interoperability between AMR/AMI systems, monitors and valves that may be connected to them, communication and programming devices as well as data formatting.

This guidance manual covers most aspects of AMI projects. It is a compilation of new as well as updated material created and compiled by the author over some forty years of research, consulting and working with utilities in the areas of water meters, AMR, AMI, customer service, information technology, and water conservation. It provides a practical structure for thinking about and managing AMI projects, as well as tools and examples.

AWE’s report, Smart Practices to Save Water: An Evaluation of AMI-enabled Proactive Leak Notification Programs, presents an analysis from four participating utilities with AMI-enabled leak notification programs - Forth Worth, TX, Sacramento, CA, Sacramento Suburban Water District, and San Francisco Public Utilities Commission. The analysis used hourly AMI data to assess whether the leak notification program resulted in statistically significant reductions in water use, mean leak formation (how often leaks occurred), and mean leak duration (how long leaks lasted) for different programs at all four utilities. The report outlines steps that other utilities can replicate based on varying data availability and the leak notification program system design.

A dedicated irrigation meter is a water meter that exclusively meters water used for outdoor watering and irrigation. For many years utilities installed these meters at parks, road medians, and playing fields, but more recently it has become common practice to install a separate meter for outdoor uses at many large sites with a significant irrigation demand. 

There is a cost associated with installing meters, but there is also a greater revenue potential for the utility, as high water-using customers will now be billed for the water that they actually use. However, water agencies should be prepared for the reductions in water consumption after metered billing is implemented.

Traditional water meters are read monthly or bi-monthly by a meter reader and a water bill is generated from this manual reading of the meter. "Smart" meters can be read remotely and more frequently, providing instant access to water consumption information for both customers and water utilities.

For various reasons of practicality and economics, many apartment buildings and strip malls receive water through one “master” meter. This removes the accountability of water use from the tenants, which have the most control over water use efficiency.