POWER PROJECT

New Zealand Herald, Volume LXXIII, Issue 22319, 17 January 1936, Page 11

POWER PROJECT

CESSATION OF WORK WAIKAREMOANA SCHEME ORDER FOR SUSPENSION FUTURE IN THE BALANCE [BY TEI.Kf<RATII OWN correspondent] GISBORNE, Thursday Efforts to.tap a huge body of water in Waikaremcana by means of a tunnel through the hillside near Panikeri, and so control the flow of water to the turbines at Ttiai, and furnish means for extending the Tuai power scheme, were suspended, last evening, when men engaged on the work were notified that they would be offered alternative employment on road improvement works near the lake. It is not yet. clear whether work on the tunnel is to lie finally closed down, the notice so far given being one of suspension. Doubtless the order has developed ns a result of the visit by the Minister of Public Works. Hon. P. Scmple, to the site of the extension scheme in December. ,Mr. Scmple then indicated that the work was full of difficulties, and that its continuation would depend upon developments of the immediate future. When the Minister visited the site he expressed no enthusiasm concerning the project to drive a tunnel through the seaward wall of tho lake, which is fissured in all directions and full of leaks, through which the water escapes from the lake into the bed of the Waiknrctahekc' Stream. This is an overflow from the lake, which is bridged near the point at which the road from Wairoa debouches upon the lakeside. It carries only a small portion of water which is subject to fluctuations according to the level of the lake. Intention ol Engineers It was the intention of the engineers in charge of the Tuai project to provide a steady and controlled flow of water from the lake through a tunnel, for which preparations have been in hand for the past 12 months, but those who accompanied the Minister on his visit to Waikaremoana last month saw sufficient to convince at least the informed layman that the work was not without considerable difficulty and hazard. Work on the tunnel driven from the outer face of the fissured rampart had been suspended for the time being owing to the tunnellers having encountered a strong flow of water from one of the hillside cracks, which effectually barred their progress on the horizontal plane. It was hoped to stop this flow by drilling down through the hill from above and grouting the fissure with cement, after which the tunnelling could proceed through a wall of concrete. This drilling was in progress when the Minister went into the tunnel to inspect the face. The shattered nature of the country was well illustrated by the amount of timbering which had been found necessary throughout the length of approximately 160 ft. to which the horizontal tunnel had been driven. Further evidence of tho difficulties of the work was provided by an inspec- i tion of the shaft driven from the saddle \ of the rampart within a few chains of 1 the lake down to the approximate level j of the tunnel.. This shaft, 70ft. deep, j has been sunk through alternate layers ! of rock and concrete, grouting bavins: i had to be resorted to frequently to seal of! thp water fissures, which threatened to hold up the work. Impressed with Difficulties The Minister made a descent into the shaft and. although he was noncommittal in his remarks on return- ! ing to the surface, he was obviously impressed with the natural difficulties which had delayed operations. This shaft was intended to carry in the completed scheme one of the two valves through which the flow of water from the lake would be regulated. At present the amount of water escaping through the Waikaretaheke into Lake iKaitawa, and thence being diverted through tho pipe line to • the Tuai power station, is only sufficient in periods of drought to feed two turbines, whereas the powerhouse is equipped to produce power from three turbines. If the regulating scheme were carried to success, it would be possible not only to produce one-third more electricity from the present installation at Tuai, but also to develop a further phase of the general Waikaremoana scheme and erect another power house further down tho valley to use the additional head of water thus provided. Should the suspension of work on the tunnel prove a preliminary to the closing down of the work altogether, it will be a severe blow to the hopes of the grand scheme of development, in which Waikaremoana water was to have been used over and over again to produce electricity in what was destined to be the major power unit of the North Island,