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Water efficiency calculator

Water Efficiency
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We will calculate the daily use based on the figures in the table below and the number of people in your household. Discover how water efficient you really are...

Enter figures for your entire household.

Water efficiency calculator figures*

Equipment/task Water usage
In the bathroom
Toilet (dual flush) 4.5 litres per flush
Toilet (age 2001 - present) 6 litres per flush
Toilet (age 1990 - 2001) 7.5 litres per flush
Toilet (age pre 1990) 9 litres per flush
Water saving cistern device (such as a HIPPO or Save-a-Flush bag) Reduces water usage by 1 litre per flush
Shower - electric 6 litres per minute
Shower - mixer 10 litres per minute
Shower - power 16 litres per minute
Tap running 6 litres per minute
Bath 80 litres per bath
In the kitchen
Washing up by hand 15 litres per wash
Dishwasher 15 litres per cycle
Washing machine 54 litres per full wash 30 litres per half load
In the garden
Hose 6 litres per minute
Sprinkler 10 litres per minute
Watering can 7 litres per watering can
In the garage
Hose 6 litres per minute
Bucket 10 litres per bucket

Drinking and cooking water has not been included as it is not recommended that you limit this use. We have added 6 litres of water per person per day* for this calculation.

*Source: Waterwise