Water Meter Installation

Water is a shared public resource. Managed correctly, it's a renewable resource for all those relying on it. But if it's not, systems risk water outages that can endanger public health. Source meters provide information that water systems need to manage their supplies, especially during emergencies and under stressed conditions. Service meters provide customers with individualized information to help them understand their consumption patterns.

Meters provide instantaneous hourly, daily, weekly, monthly, seasonal, and annual information on usage variations. These changes in usage tell the story of how efficiently water is used. This helps water managers understand where and how to invest in their water system, ensuring a safe and reliable supply of water for their customers. You cannot manage what you cannot measure.

In 2003, the Legislature mandated that most Group A water suppliers must not lose to leakage more than 10 percent of the water that runs through their distribution system. Installation of source and service meters and collecting that information lets water systems know whether or not they've met those standards. They then report this information to us each year.

Water Use Efficiency (WUE) Report

Through the Water Use Efficiency (WUE) annual performance report:

  • Source meter information is reported as Total Production. This is all metered water that enters the distribution system through an intertie, from a water source, or the treatment plant for the year. Every municipal water supplier in the state of Washington must install a source meter.
  • Service meter information is reported as Authorized Consumption. This is all metered water from each service connection and unmetered authorized uses for the year. Every municipal water supplier in the state of Washington must install service meters, except mobile home parks, RV parks, campgrounds, and multi-unit buildings.

Metering each individual connection is critical to understanding overall water efficiency. Without measuring water use at both the source and service connections there is no effective way to measure water loss, customer consumption, or unauthorized use.


Municipal water suppliers that meet the WUE requirements are important for water conservation. Our compliance strategy emphasizes technical assistance by providing the tools necessary to meet the WUE requirements. We prioritize enforcement actions against the most serious violators, especially those that endanger public health.

Additional Resources

Meter Information for: