Te Anau ‘Saturation' Problem

Press, Volume CX, Issue 32351, 17 July 1970, Page 24

Te Anau ‘Saturation ' Problem

(N.Z. Press Association) WELLINGTON, July 16. The situation at Lake Te Anau if the level of Lake Manapouri were raised had not been looked at as thoroughly as it might have been, the Commission of Inquiry into Lake Manapouri was told today by the chairman of the National Parks and Reserves Authority (Mr R. J. MacLaughlan). Questioned by Mr F. D. O’Flynn, who appeared for the Save Manapouri Commit-

tee and the Royal Forest and Bird Society, Mr MacLaughlan said work at Te Anau could involve a greater undertaking than was anticipated. The work would have to be done when the lake level was down. If Manapouri were raised the lake would be at levels as high as 673 ft above sea level. The natural mean level of the lake was 663 ft, the lowest level being 659 ft and the highest (recorded in the floods of 1967) 670.5 ft. Extreme fluctuation under natural conditions would be lljft, with an average fluctuation of 7ft being the greatest in any one year. If Manapouri were raised and a control structure for Lake Te Anau built the range of fluctuation would have variations of up to 20ft,

the highest level being 673 ft and the lowest 653 ft

Raising the level of Manapouri would affect Lake Te Anau and everything along the shore line. The greatest effect would be in the township of Te Anau, where the problem of saturation could be expected. Saturation would have an adverse effect on the shore area and create sewage disposal problems. To be efficient septic tanks required to be a minimum of 2jft above water level, but a level of 4ft was desirable.

To Mr MacLaughlan’s knowledge no work had been done on a clearing programme round the shoreline at Te Anau to provide for raising of the level from Manapouri. However, 6ne report

showed that some 380 acres would require remedial work, and that an allocation of $175,000 had been considered. This represented an expenditure of $5OO an acre, which was thought to be low.