Daily water consumption

Update 18 March

Demand is still tracking pretty high for this time of year – just look at the level of demand this year compared to the past two years!*
Supply from rivers in Wainuiomata has dropped out, and now we’re using a lot more water from our storage lakes.
Lake usage has averaged about 41MLD over the last week, and levels have dropped 9% in the last week.
Catchments are still very dry, and there isn’t much rain on the forecast! Please continue to observe water restrictions until they come off, and of course, always use water wisely.
*These graphs indicate demand in Porirua, Wellington, Lower Hutt, and Upper Hutt.

Regional supply and demand graph - 18 March

Water demand map 18 march

Three years of demand graph - 01 October-31 March

three years of demand 18 march

ML/Day (MLD)

Million litres per day.

Available supply 

Available supply is the amount of water we can take from our three sources:

  • Hutt River
  • Combined flow of the Wainuiomata and Orongorongo rivers
  • Waiwhetu Aquifer - a natural underground reservoir beneath the Hutt Valley that is fed by river-water seeping down into the ground.

In the summer months supply typically goes down, as there is less rain. There is also a cap on the amount of water we can take from our rivers, due to environmental reasons. 

We have two large storage lakes at Te Marua as back-up to the river supply. The lakes are filled from the river when it is clean and there is plenty of water available.

During a typical Wellington summer we normally tap into our lake supply in February/March.


Demand relates to the amount of water the region in using. It usually increases in summer due to residential outdoor water use increasing.

To comfortably supply demand in the region, we have a target of 170MLD.

Every year to help us manage summer demand garden watering restrictions in Wellington, Lower Hutt and Porirua are in place during daylight saving (and all year round for Upper Hutt). However, when there are long periods of dry weather around the region these restrictions can be increased. 

There are currently garden watering restrictions in place around the region.