Crucial dams gasping for rain

By KEVIN TAYLOR and CATHY ARONSON

Water levels in Lake Taupo are hovering only 15cm above the legal minimum to supply the hydro dams that are crucial to New Zealand's power supply.

The eight Waikato River dams that rely on Taupo water normally supply 12 to 13 per cent of the nation's electricity in winter.

But the owner of the dams, Mighty River Power, said yesterday that it was supplying only 8 to 9 per cent of the country's needs because of one of the driest periods on record.

Doug Heffernan, chief executive of the state-owned generator, said little rain had fallen since May. Only a week to 10 days' reserve water would be left in the lake if the company drew it down to the bare minimum, although it did not intend to do so.



The water levels in the country's other main hydro lakes are still falling. Their generating capacity yesterday - 1328 gigawatt hours - is 56 per cent of the average for this time of the year.

During the 1992 crisis, the levels fell to 500 gigawatt hours.

The levels of southern hydro lakes on Sunday were: Manapouri, 32 per cent full; Te Anau, 39 per cent; Wakatipu, 28 per cent; Wanaka, 37 per cent; Hawea, 16 per cent; Ohau, 22 per cent; Pukaki, 41 per cent; and Tekapo, 34 per cent.

But the amount of water flowing into the lakes is rising. The latest measured inflow was 4 per cent above average.

Conservation efforts have reduced power consumption by 5.1 per cent across the country - a little over half the 10 per cent saving the Government says is needed to avoid blackouts.

Wholesale power prices have dropped from 33.55c to 33.02c a kilowatt hour, but are still 3c higher than last week.

With Lake Taupo close to shut-off point, Auckland's Mercury Energy, owned by Mighty River Power, is relying on other suppliers.

Mr Heffernan said Taupo had been low for more than two months and the dams were generating only three-quarters of the power they normally would at this time of year.

The cabinet has approved a $2.25 million electricity conservation campaign, augmented by incentives for customers to cut use.

Environment Waikato says low lake levels can cause erosion and affect aquatic breeding habitats.

But the regional council was not sure if it could enforce the legal minimum water level because the dams were built before the Resource Management Act came into force.

Projects manager Dennis Crequer said the minimum and maximum lake levels would be considered in Mighty River Power's application for a 35-year consent to operate its dams.

Taupo deputy harbourmaster Les Porter said the lake had been low before, but this time there had been no rain for six weeks. "We need rain - it's as simple as that."

Worries about high power prices and the call for energy conservation were being felt in many quarters yesterday. Age Concern national chief executive Garth Taylor said he had heard of elderly people going to bed once it got dark, then getting up with the dawn.

Mr Taylor said it was important for the elderly to contact their power companies to find out whether prices had increased for them.

While wholesale prices of electricity had soared, retailers had passed on very few increases.

The 85-store Woolworths chain, which includes Big Fresh and Price Chopper supermarkets, said yesterday that it was turning off one in 10 lights across the chain - 20,000 in total - and reducing air-conditioning from 22 to 20 degrees.

Property services manager Bill van Tilburg said he expected the company to cut 10 per cent off its power bill, saving enough electricity to power more than 1000 average-sized homes for seven days in winter.

Feature: Electricity

Energy Efficiency and Conservation Authority