FIVE STATIONS Full Development Of Waitaki

Press, Volume CVIII, Issue 31750, 6 August 1968, Page 1

FIVE STATIONS Full Development Of Waitaki

(From Our Own Reporter)

WELLINGTON, August 5.

The Government has approved in principle the total development of the Upper Waitaki Valley for hydro-electric use. This was announced today by the Minister of Electricity (Mr Shand).

Early approval in principle of this scheme was one of the recommendations i n the Power Planning Committee report recently tabled in Parliament.

The scheme will change the course of the rivers draining Lakes Tekapo, Pukaki and Ohau, and raise Lake Pukaki by more than 100 feet. Five new power stations will be built and the output of the existing Waitaki stations will be increased by the extra storage made available. The Government’s decision

is subject to any requirements the National Water and Soil Conservation Authority might lay down with regard to the design and operation of the scheme.

This authority was recently set up under the Water and Soil Conservation Act.

“The first step in the scheme will be the establishment of a construction township at Twizel,” said Mr Shand.

“This work will be started as soon as possible and will provide employment for some of the men on the Aviemore scheme. The township will be extended as the scheme progresses and may have a peak population of about 5000.

Other Features

“The New Zealand Electricity Department will seek approval for other features of the scheme at intervals over a period of years. “The timing depending largely on the rate at which Consolidated Zinc takes up its entitlement to power from Manapouri. The scheme is not expected to be completed until the 1980 s,” said Mr Shand.

The early features of the development Include:—

(1) An earth dam across the outlet from Lake Pukaki, about a quarter of a mile downstream of the present control works. The approval for the future raising of the lake envisages a maximum storage level of up to 1746 feet (127 feet higher than at present), and a design flood level of up to 1756 feet (122 feet higher than at present). A study of the area that might benefit from irrigation has shown that 3ft of stored water in the lake would meet the annual requirements. The above figures allow for possible extra height for this purpose. The raising of Lake Pukaki does away with the necessity for altering the level of Lake Ohau beyond its natural. range. (2) Canals and e tunnel to divert the outflow from Lake Tekapo into Lake Pukaki.

(3) Two power stations, Maryburn and Pukaki, with a combined capacity of 160 megawatts, to use the water en route from Tekapo to Pukaki. (4) Ostler power station, 264 megawatts, and the associated canals which will carry to it the outflows from Lakes Pukaki and Ohau.

On present construction costs the scheme will cost a little over slBBm, and on this basis the unit cost is estimated at 0.35 c. This compares very favourably with any possible alternative source of power, said the Minister. More Employment Commenting on the effect of the scheme on employment, Mr Shand said that it would require 1200 to 1500 men at the peak of construction; the approval in principle assures future employment for workers who have given long and faithful service on hydro-electric construction in the past. The decision to go ahead with construction of the Twizel township will provide immediate employment for about 100 of the men presently engaged at Aviemore. Employment for others is expected to be available on the construction of the Te AnauManapouri control works. "The ways in which the scheme will affect farming, property and scenery have been thoroughly investigated,” the Minister said. “It has been established that the hydro-electric development can be reconciled with future irrigation requirements. Farms Affected ‘Some existing farm development—fences, water supplies, access, boundaries and buildings—will have to be replaced, but there is no reason to suppose this cannot be arranged satisfactorily. “The farms most affected will be those round Lake Pukaki; the Lands and Survey Department and Ministry of Works have been authorised to open discussions with pastoral run lessees on the effects of any purchases or amalgamations which may be necessary. “The loss of income, actual and potential, from the farm land flooded will be small compared with the potential gain from irrigation which could only be possible in conjunction with the hydro-elec-tric scheme, and much less than the value of energy obtained from the scheme,” he said. Mr Shand said that apart from dams the main property affected be the Tourist Corporation Hotel at Pukaki, which could be satisfactorily relocated. The Nature Conservation Council had been consulted and did not object to the lake raising and control measures envisaged.