The region's water comes directly from rivers and underground (aquifer) sources that are dependent on rainfall. Our water supply system has relatively little storage capacity, so we rely largely on there being enough water each day from our rivers and aquifer to meet that day's water use.

During summer, extended periods of low rainfall can restrict the amount of water available to treat, while causing water use to increase by as much as 50%. Our ability to treat and supply enough water to meet demand at these times can be tested.

In recent times we have been able to supply all demand for water in most years without great difficulty, due to favourable rainfall patterns. However, the population that we supply to is steadily increasing, so meeting all demand will become increasingly tricky during dry periods. Reducing summer-time demand for water, especially for garden watering, helps to avoid the need for tougher watering restrictions

Every litre of water we supply requires electricity to treat and pump it and treatment chemicals to make it safe and clean, and every litre treated contributes to the amount of treatment waste that must be disposed of. Any reduction in water use therefore helps reduce the impact of supplying water on the environment as well as reducing financial costs.

The most extreme peaks in water use are largely caused by high levels of garden watering on top of regular indoor water use during summer. A garden hose can easily deliver 20 litres of water every minute, which is equivalent to a bathtub every five minutes. An hour of watering can use as much water as a family of four would normally use on a winter's day. Few people realise how much water they use in their garden or think of it as an area where they could make savings, but it's easy to see how careless watering or leaving the tap on by accident can waste a lot of water!

Each summer we run a publicity campaign to encourage gardeners to use water with care , which helps to keep plants healthy and conserve water.