Editorial: Patch leaks and raise awareness

OPINION: Water, like air, is something we take for granted. We expect to be able to use as much as we want, when we want, without any impact on our wallets.

But, as a report to be considered by a Wellington City Council committee on Thursday points out, there is a real cost to water use. It might descend from the heavens, but it has to be stored, treated and distributed on Earth.

Until now residents of Wellington, Porirua and Hutt Valley have got off relatively lightly.

The pluvial nature of the region means local authorities have not had to invest as heavily as many of their counterparts elsewhere in water storage facilities.

But population growth is putting pressure on existing facilities.

The region draws its water from three sources – the Hutt River, the Orongorongo and Wainuiomata rivers and the aquifer that flows beneath the lower part of Hutt Valley.

The region's sole storage facility, the lakes at Te Marua, contain enough water for just 20 days' average use, far less, for example, than Auckland, a city in which sprinkler bans are as common as traffic jams.

The existing arrangements have served the region well but population growth has reduced the margin of error. Where once the region had sufficient capacity to cope with a one-in-50-year drought, it now has sufficient to cope with just a one-in-26-year drought.

The paper to go before Wellington City Council's strategy and policy committee on Thursday argues that the region must either find ways to reduce water use by 1 per cent per head for each of the next 15 years or begin preparing to build a dam in Whakatikei Valley, northwest of Upper Hutt.

The proposed dam would increase the region's storage capacity from 3000 million litres to 8000 million litres (or 20 days to 53 days) but it would cost $142 million. Conservation is the preferable option.

Extra capacity will eventually become necessary if the region's population keeps growing at its present rate of 1 per cent a year.

But there would be few households in the region that could not find ways to reduce consumption of a good they have till now regarded as free and limitless.

Shorter showers, fewer baths, waiting till the washing machine is full before switching it on and mulching the garden after rain are all relatively painless ways to reduce water use.

One of the options up for discussion is the installation of water meters, which would allow water suppliers to bill people for actual water use and increase consumer awareness.

Again they may eventually become necessary. Those who enjoy long showers, frequent baths and large gardens should be prepared to pay for their pleasures.

But meters are horrendously expensive. It has been estimated it would cost about $70 million to install them throughout the region.

A simpler and better option is for the councils to mount a campaign to raise public awareness of the need for conservation, and patch the leaks in the existing system.

Meters and extra storage may be inevitable, but there is no need to go down that path before it is necessary.

- © Fairfax NZ News