Can ultrasonic water meter serves as reliable evidence in water bill disputes?

Whether water bills are calculated correctly is a common issue that often escalates between residents, property management, and the water company. Older mechanical water meters can wear out over time, become clogged with dirt, or even be tampered with with magnets, all of which can cause them to lose accuracy. The advent of ultrasonic water meters has become a new solution for resolving these disputes.

Calculation Method

Ultrasonic water meter is completely different from traditional mechanical meters. They rely on probes installed at both ends of the water pipe, emitting high-frequency sound waves that are inaudible to us. They then very accurately measure the time difference between the sound waves traveling with and against the flow of the water. By combining this with the thickness of the pipe, they can calculate the amount of water flowing. This process is handled entirely by an electronic chip within the meter, and the result is directly stored as a number. This means that the water usage data is recorded electronically from the start, unlike older gear-driven meters that required manual reading and recording. This eliminates the problem of mechanical meters slowing down over time and prevents meter readers from misreading. Even more impressively, once this data is generated, it cannot be altered.

Protection Mechanism

Ultrasonic water meters typically have several layers of protection. First, critical data is timestamped and locked within the chip, making it impossible for ordinary users to modify or delete it. Second, when this data is transmitted to backend computers or servers via M-BusRay or NB-IoT, it is encrypted en route to prevent interception and modification. Finally, within the backend system managing this data, anyone who wishes to modify the data requires the corresponding password, and the system clearly records who modified what. This approach, with every step from the water meter to the backend secure and traceable, creates a complete chain of evidence that is impervious to investigation.

Detailed Records

Ultrasonic water meter can be verified using several tools. The first is a detailed record of past water usage. The system can plot daily and even hourly water consumption for a specific period of time as a graph for easy viewing, providing a clearer picture. Secondly, the water meter's own health report can be used. For example, it can record alarms indicating low battery levels, internal faults, or attempts to tamper with the meter. These records can help determine whether the meter is genuinely faulty or deliberately tampered with. Thirdly, it can be used for remote on-site inspections. Without the need for a visit, a technician can remotely read the meter's current data from a computer and compare it with the data stored in the backend system to verify consistency.

Legal Regulations

Ultrasonic water meters must comply with mandatory national testing regulations and must obtain a "certificate of medical examination" from a nationally recognized testing agency before installation. If the meter's operator adheres to proper procedures, the information recorded by the ultrasonic meter can be used as electronic evidence under the Civil Procedure Law. In fact, the court has already ruled on this point: when the user said that the meter was inaccurate but could not provide evidence to prove that the meter was indeed broken, the court accepted the data provided by the ultrasonic water meter system and calculated the water bill based on that.