Non-revenue water (NRW) represents one of the most significant challenges facing water utilities, with losses stemming from aging infrastructure, undetected leaks, and inefficient pressure management. According to a recent report from Bluefield Research, nearly one in five gallons of treated drinking water in the United States is lost before it reaches customers. It is estimated that this loss costs US utilities more than $6.4 billion in uncaptured revenues annually.

A range of advanced technologies are available to help utilities tackle NRW effectively, focusing on pipe condition assessment, leak detection, and pressure management. By leveraging these solutions, utilities can achieve significant reductions in water loss, safeguard their infrastructure, and ensure a reliable water supply for their communities.

Pipe Condition Assessment

One of the foundational steps in reducing NRW is understanding the current state of the water distribution network. Pipe condition assessment technologies, like ePulse, provide utilities with data-driven insights to prioritize maintenance and replacement efforts.

Acoustic condition assessment is a non-invasive technology using audio wave propagation to evaluate the structural integrity of pipelines. By inducing low-frequency acoustic waves and measuring their velocity through the pipe wall, the technology can estimate the remaining wall thickness and structural strength of various pipe materials, including asbestos cement (AC), cast iron (CI), ductile iron (DI), steel, and prestressed concrete cylinder pipe (PCCP). The system identifies areas with structural weaknesses while simultaneously detecting existing leaks, enabling utilities to focus resources on the most at-risk segments. This targeted approach is far more cost-effective than age-based replacement, which can result in replacing pipes that are still in good condition.

This technology provides a detailed report, including leak locations, percentage wall loss, and qualitative assessments (good, average, poor) for each pipe tested. If historical installation data is available, the estimated remaining service life of each segment is also provided. This approach allows utilities to extend the life of their assets and avoid unnecessary expenditures on pipe replacement. Replacing the worst pipes first is the best way to reduce NRW in the long-term.

Leak Detection

Early and accurate leak detection is essential for minimizing water losses and preventing catastrophic failures. Permanent acoustic monitoring systems have improved this aspect of NRW management over the last decade.

The EchoShore® permanent leak monitoring system uses sensors that can be deployed on fire hydrants or valves, making use of existing infrastructure for comprehensive coverage. The system employs advanced acoustic analysis and AI-driven algorithms to identify leaks as they develop, sending real-time alerts to utility operators via the Sentryx™ Water Intelligence platform. This proactive approach allows for early intervention, reducing repair costs, environmental risks, and water loss.

There are two options based on pipe size:

• EchoShore-DX: Designed for distribution lines, it enables utilities to identify leaks early, monitor their progression, and prioritize repair schedules.
• EchoShore-TX: Tailored for large transmission mains (16 inches and above), it uses sensitive hydrophone sensors to monitor critical supply lines, including those crossing bridges, major roads, or serving industrial areas. This system is particularly valuable for mains with a history of rupture or where service disruptions would have significant consequences. The sensitivity of the
  hydrophones allows for larger spacing of sensors, an average of half mile between access points.

All data is sent and processed in the platform that is used to monitor, control, operate, and monetize the water distribution network. Intuitive dashboards with mapping make it easy to visualize data. It provides KPI dashboards, sensor status, and there is a mobile app for field crews to update investigation results and upload photos, streamlining the entire leak management process. The Echoshore platform is assisted by human data analysis as well. Each site is monitored by a dedicated analyst that reviews alerts in the network. This added layer of review reduces false positives leading to a best in class hit rate of over 80%.

Pressure Monitoring and Management

Pressure management is a proven strategy for reducing leakage and pipe bursts, both major contributors to NRW.

i2O® advanced pressure management integrates real-time flow and pressure data with cloud-based analytics. By creating a flow-related head-loss curve, the system’s controller dynamically adjusts the pressure reducing valve (PRV) outlet pressure to maintain target pressures at critical downstream points in the network. The algorithm updates daily, ensuring optimal pressure settings as demand fluctuates. This approach minimizes over-pressurization, which is a leading cause of leaks and bursts, and ensures stable, efficient network operation.

The PRV monitoring and control systems deliver more accurate, stable, and smooth pressure control, resulting in fewer leaks, reduced open-tap demand, and extended pipe life. Pressures in a network fluctuate daily and without real time control, most water systems operate at higher pressures than needed especially at night. By limiting pressure to only what is needed the overall leakage in a system is reduced and fluctuations in pressure are minimized.

West Coast Success Story

The City of Sandy, Oregon successfully implemented a comprehensive suite of water management technologies in 2024 to dramatically reduce water loss and operational costs. With only 4,200 service connections and a lean staff of 10, the city needed smart solutions to manage its water system efficiently.

Advanced Metering Infrastructure (AMI): Sandy deployed Mueller Solid State Registers with a complete AMI network featuring five collectors and six repeaters. This eliminated the monthly cost of manual meter reading while enabling daily, on-demand readings and remote monitoring of hard-to-reach areas. Reliable meter readings are essential for a water loss plan. If the meters are dated and the consumption is inaccurate then it is difficult to track improvements from other technologies. For this reason, an upgraded AMI system was the first step in Sandy’s NRW journey.

Three-Phase Technology Implementation

In phase 1, the city adopted a systematic, data-driven approach to quantify water loss, identify leaks, and optimize pressure management. This initiative began with isolating a pressure zone and using a combination of insertion meters in Singer® PRVs (Pressure Reducing Valves) and i2O pressure loggers to measure incoming water volume versus consumption recorded by AMI meters. This analysis revealed a significant 33% water loss in the targeted zone. This zone was the first district metered area in the city, which allowed them to target water loss in the zone and track improvements hourly.

Phase 2 was identifying leaks, using the EchoShore-DX fixed leak monitoring technology installed on fire hydrants to detect the faint sounds of leaks. These sensors continuously uploaded data to the Sentryx platform, to analyze acoustic signals and flag potential leaks for staff review. Within the first month the system enabled the city to locate a 7-gallon-per-minute leak, reducing average water loss in the district metered area (DMA) by 15% and saving over 4 million gallons of water and $33,000 annually.

Phase 3 was the implementation of pressure management in Zone 4 using five i2O pressure loggers and two Singer pressure control valves. By lowering pressure during low-demand periods, the city reduces stress on pipes and further limits water loss. These efforts have contributed to a further reduction in water loss of 5% in the targeted DMA

Results: The integration of these technologies has transformed daily operations. Automated alerts from meters and loggers now allow staff to quickly triage and respond to issues, reducing unnecessary site visits and focusing resources where they are most needed. One staff member can efficiently review and manage alerts, leading to faster identification of leaks, tampering, or no-flow events. Technology
does not replace a water operator, but it can allow one operator to perform the tasks of many if implemented correctly.

“For our small team, using technology to pre-screen issues saves tremendous time,” says Joe Johanesen, Water Supervisor for the City of Sandy, OR. “Instead of driving around and checking every yard, we only visit locations that truly need attention.”

The table below summarizes each of the NRW approaches and their strengths, a combination of the right technology can lead to improved distribution system management.