How we calculate our charges

Business customer? Go to wastewater pricing plans

Your monthly bill

Your Watercare bill sets out the water and wastewater charges for the month.

View sample bill

Water charge

We charge per 1,000 litres (= 1 kilolitre) of water supplied to your property, as measured by your water meter.

This charge is volumetric: it is based on the amount of water you use each month, as measured by your water meter.

Find out more about our water meters.

Wastewater charges

There are two parts to your wastewater bill:
  • Fixed charge: this pays for maintaining the wastewater network and is not based on how much water you use.
  • Volumetric charge: this pays for collecting and treating your wastewater.

Fixed wastewater charge

All properties with a water meter and a wastewater connection pay a fixed wastewater charge as well as the volumetric water charge. This pays for maintaining the public wastewater network.  

The fixed wastewater charge is payable all year, whether the property is vacant or occupied. This is based on the number of days that your bills covers, and not the amount of water you’ve used.

Each month, your bill shows the pro rata (proportional) wastewater charge for that billing period (number of days). 
For example, if the annual fixed wastewater charge is $218, the daily rate is 218 divided by 365 days = 60 cents. So for 30 days the charge would be about $18.

Volumetric wastewater charge

Unless you have a secondary water supply, such as a rain tank, or live in an apartment, we base the wastewater charges on 78.5 per cent of the water volume coming into your property, as measured by the water meter. This assumes that, on average throughout the year, 78.5 per cent of the water becomes wastewater by going down the drain via your kitchen sink, dishwasher, shower, bath, washing machine, toilet, etc.  

Allowance for outdoor activities

We do not charge you for wastewater for the remaining water (21.5 per cent). We allow this for your outdoor activities where water does not enter the wastewater network, such as: 
  • watering the garden
  • washing a car or boat
  • waterblasting the house.

Why are apartments charged at 95 per cent for wastewater?

We normally base residential wastewater charges on 78.5 per cent of the volume of water used on the property. This leaves an allowance of 21.5 per cent for typical outdoor activities such as watering the garden or washing the car, where the water does not enter the wastewater network. 

Residents in apartment complexes don’t typically use water for these activities – most water they use drains directly into the wastewater network. There is an allowance of 5 per cent for outdoor activities in apartments.