Crater Lake threat

Ruapehu Bulletin, Volume 14, Issue 675, 25 February 1997, Page 1

Crater Lake threat

Mt Kuapehu s Crater Lake once again poses a danger but one not likely to arise until the lake refills in 3-4 year's time. This is the finding of a scientific study group which has been assessing the integrity of the crater lake rim-wall where a wedge-like infill of loose ash, scoria and ice has formed Over the lake's old outlet creating a l Om ' dam ' . The present lake level is well below the crater rim and poses no immediate danger but when water levels reaches the temporary 'dam' it will either seep through the sodden mass or, more probably, cause the 'dam' to collapse from the pressure of water within the crater rim. In this event the resulting flood is likely to be even more devastating than the 1951 Tangiwai disas-

ter, depending on what level the water has reached beforethe 'dam' collapses. "This prospect has led us to develop a strategy to find ways of dealing with the problem including some form of engineering intervention," said Conservation Department scientist, Dr Harry Keys. The Department of Conservation together with ECNZ, Manawatu-Wan-ganui Regional Council, TranzRail, Transpower, NZ Army and Winstone Pulp International commissioned the study in June but is was postponed until snow had disappeared from the crater rim. The study has been undertaken by scientists from the Institute of Geological and Nuclear Sciences and the Department of Conservation and will involve discussions with local iwi.