McLean, J.D. 1975 Ohau B and C power project : Ruataniwha damsite, geological report on investigations. Lower Hutt: New Zealand Geological Survey. New Zealand Geological Survey report EG 220 16 p.
Abstract: As part of the Ohau B and C Power Project (Layout on Fig. 1) the Ohau River will be dammed about 110m upstream of the old Ohau Bridge. A 35m high earth dam with a crest level of 461.5m will span the rock gorge and be 'bonded' to the rock on both sides of the present channel. The impounded water will form Lake Rautaniwha (surface level 458.5m) from which water will be taken by canal to the Ohau B powerhouse. A spillway and diversion structure will be combined in a cut on the right bank. S.H.8 will be realigned across the crest of the structure. The proposed development is shown on Figure 2 is taken from MWD drawing L7861/23. [Lovatt (1973)]. The site has been investigated intermittently since 1961 by drilling, shaft sinking and seismic surveying. This report presents the combined results of all these investigations as well as information obtained from recent geological field work. Construction materials are not discussed. A sequel to this report will deal with the investigations currently being undertaken (May 1975) for construction materials. (auth)