Water Tight Blog

Master and Slave Water Metering Systems: A Fair Way to Divide the Bill?

Master Water Meter in Canberra

Many apartment complexes use a master and slave water meter arrangement to bill residents for water usage. This system can be a fair and effective way to allocate water costs, but it’s important to understand how it works.

How It Works

A master meter is installed at the main water supply line entering the complex. This meter records the total amount of water used by the apartment complex.

Each individual unit then has its own slave meter. This meter records the amount of water used by that specific unit.

When water is used in a unit, both the master meter and the slave meter will register the consumption. However, the common property areas, such as some hose taps and irrigation, typically don’t have their own slave meters.

Calculating Common Property Consumption

The water consumption of the common property areas is calculated by subtracting the total consumption of all the slave meters from the total consumption recorded by the master meter. This difference is then allocated as consumption, typically based on the size of each unit or the number of occupants.

Advantages of Master-Slave Metering

  • Fairness: This system can be fairer than simply dividing the total water bill equally among all units. Units that use more water pay more, while units that use less water pay less.
  • Water conservation: Master-slave metering can encourage residents to conserve water, as they are aware of their individual usage and the cost associated with it.
  • Leak detection: If the master meter reading is significantly higher than the sum of all the slave meter readings, it could indicate a leak in the common property areas.

Disadvantages of Master-Slave Metering

  • Cost: Installing and maintaining master and slave meters can be expensive if not done during construction.
  • Inaccuracy: Meter readings can be inaccurate, which can lead to disputes over billing. This is less relevant when the water meters are owned and managed by the water authority (Icon Water)
  • Complexity: This system can be complex to manage, especially in large developments unless managed by the water authority (Icon Water)

Overall, master-slave water meter arrangements can be a fair and effective way to bill residents for water usage. However, it’s important to be aware of the potential disadvantages of this system.

I hope this blog post has been helpful. If you have any questions, please feel free to contact us.

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