Water is a scarce resource around the world. It is anticipated that clean water will become even more precious with the impact of climate change – in many parts of the world, the next 50 years will be drier than the last 50.

Sustainable home water use

All the signs indicate that water shortages will become more and more common in many parts of New Zealand in future.  How can homeowners adapt to such a future?

The first step is to treat water like the valuable resource it is and use it as efficiently as possible.  This will help keep water in our reservoirs, rivers and underground sources and reduce the need to build more infrastructure, such as new dams and water treatment facilities, to supply us with water.

A family of four in New Zealand uses about 500L per day not including water used in the garden – a garden sprinkler can use 900 litres an hour.  In a typical home, about 25 per cent of water is used for baths and showers, 25 per cent for flushing toilets, 10 per cent is used in the kitchen, 20 per cent is used in the laundry and 20 per cent for gardening.

Many district councils have published excellent guides on how to save water around the house. They involve simple things that any of us can do.

The Waitakere City Council has produced a number of excellent guides about sustainable homes here are some of their guides relating to water.

Saving Water (Size 99K, PDF)

We waste an enormous amount of quality drinking water. The average three-person household in Waitakere City uses about 485 litres of water per day.

Heating water (Size 611K, PDF)

Water heating probably accounts for 45% of your annual household energy use. Most of us have electric storage hot water systems, which are often inefficient and wasteful.

Using Rainwater (Size 189K, PDF)

We collect rainwater from a relatively small area and distribute it over the entire urban area of the city.

Wastewater (Size 246K, PDF)

Wastewater is the water we dispose of from our homes, offices and industry. It comes from toilets, sinks, showers, washing machines and industrial processes and was historically called sewage.

Gardening with Water (Size 198K, PDF)

This document offers some simple tips on how to manage your garden and lawns for dry periods, which plants can cope best, and how to manage an irrigation system (if you must).

About 65 per cent of water used in the house is for non-potable purposes (flushing toilets, laundry and gardening).  Rainwater collected from the roof can be used safely to meet these needs instead of treated water.  Rainwater collection systems also reduce the amount of water flowing into storm runoff systems which means these can be smaller and less costly.

Cold water being poured into a glass.