Pattern Approved Water Meters – What’s the Story?

March 2021

Dale Harris, General Manager at HR Products has taken the time to summarise Australia’s new regulations around pattern approved water meters.

Over the past few years, there have been a number of changes relating to the metering of water from licensed water entitlements. These regulations stipulate approved or compliant water meters are now required for all instances when non-urban water metering is required.

The National Framework for Non-Urban Water Metering came into effect nearly 10 years ago in July 2010. The Framework agreed to by Australian, state, and territory governments aim to deliver nationally consistent non-urban water meter standards to increase measurement accuracy.

What's going on with Pattern Approved Water Meters in Australia

The National Framework stipulates that all non-urban water meters shall be:

  • Pattern approved by the National Measurement Institute (NMI)
  • Installed in compliance with the Pattern Approval certificate
  • Validated by a certified validator (accredited by Irrigation Australia Ltd) after installation

In terms of the rollout dates and local requirements, the relevant state and territory government departments have produced their own codes, policies, and guidelines that operate within the National Framework.

It is recommended that you consult your own state legislation to be fully aware of any new regulations and deadlines for installing approved water meters. Irrigation Australia Ltd has published links to the state and territory resources relating to the current requirements on their website.

The following summary will give you a broad overview of the current situation.

What is a Pattern Approved meter?

To achieve Pattern Approval, water meters are tested for compliance with the Australian Standard for Non-Urban water meters (AS4747 If the meter passes testing, it is pattern approved as compliant with the requirements for closed conduit meters (NMI-M10); or with the requirements for open channel meters (NMI-M11).

Meters must be very well designed, manufactured with high-quality materials, and be very reliable to comply with the testing requirements. In addition, they must be installed according to the pattern approval certificate to be compliant in the field.

Mechanical versus Electromagnetic Meters

There are two main groups of pattern-approved water meters – mechanical and electromagnetic. They both have their fit in irrigation applications.

Electromagnetic meters (mag meters)

Positives: Suitable for dirty water and abrasive water, shorter straight pipe lengths for installation, dual-direction of flow, can be used on large diameter pipes (>400mm)
Negatives: Need power, very expensive, complicated installation and validation, digital output not always easily read or interpreted by telemetry devices, can be disturbed by magnetic fields (such as electric fences, generators, variable speed drive).

Mechanical meters (Woltman turbine meters)

Positives: Very reliable, easy to install, very cost-effective, conventional dial display as well as pulse output readable by all telemetry devices, no power required
Negatives: Can be fouled by debris, a single direction of flow, limited to pipes up to 300mm diameter

Who can install Pattern Approved water meters?

Being easy to install, most mechanical pattern-approved water meters can be installed by qualified irrigation contractors. However, state and territory policy requires the meters are validated by a certified meter installer and validator, who have undergone training and accreditation through Irrigation Australia Ltd.

Electromagnetic water meters must be installed by trained professionals only due to the more complicated installation requirements.

Disclaimer: The information provided in this article is general in nature and should not be relied upon in terms of compliance with local, state, and national regulations. Please consult the necessary authorities to obtain the most up-to-date documentation and compliance requirements.