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SOUTH ISLAND. Maelboeough. The rivers suggested as sources of power in this district are the Pelorus and Rai, Wakamarina, Wairau, Waihopai, Awatere, Clarence, and Conway. In all cases the works required to utilise these rivers would be of the same general character, consisting of weirs, settling-tanks, and races along the hills to convey the water to selected points, to get as great an altitude as possible. No detailed examination has been made of any of the rivers to determine the best location or possible magnitude of any scheme to utilise any of them. The Surveyor-General has supplied information regarding the fall obtainable in the Clarence, Awatere, and Wairau. This information is given in the sections for these rivers attached hereto ; also the drainage-areas above each of the points named for each river. No low-water or any gaugings have been obtained for any of the rivers in this district, and the lowwater flow is only a matter of surmise. It will be generally relatively low, as there are no lakes to equalise the flow, nor bush to any extent on the large rivers—the Clarence, Awatere, and Wairau. The Waihopai, a tributary of the Wairau, is worth investigating. It is possible that it might be found sufficient for all industrial purposes for Blenheim and surrounding district. If not, an investigation of the upper reaches of the Wairau or Awatere should be made. Clarence Rivee. The head-waters of the Clarence River could be diverted by a tunnel under Jollies Pass, and taken to a point in the valley of the Waiau-ua just below the Jollies Pass Hotel. The difference in level between the probable intake and the power-station would be 1,160 ft. Probably about 1,100 ft. of effective head would be got. The distance between the two points is about three miles, but a conduit would be longer. The drainage-area tapped would be 190 square miles. No information is yet available as to the probable minimum flow in the river. The drainage-area is mountainous, reaching an elevation of over 7,000 ft., but hardly any of the main range is drained by the river. There is a small lake (Tennyson). It does not tap any large area, and would not be likely to greatly affect the flow of water, though it would help, and its effects might be increased. I think it likely that at least water enough should be available to give 15,000 to 20,000 b.h.p. The information regarding this scheme I got from Mr. Rutherford, Chief Draughtsman of this Department, who obtained a number of heights in this locality. The River Acheron joins the Clarence about seven miles down from the probable intake of the Jollies Pass scheme. To reinforce this scheme from the Acheron would require a race probably twelve miles or more long, depending on the fall in the Acheron. The junction is about 160 ft. lower than the river at the intake. The valley below the junction is narrow, perhaps sufficiently so to justify the construction of a dam to raise the water high enough to send it through Jollies Pass, and some storage might be got by adjusting the level of the tunnel. The drainage - area of the Acheron is about 360 square miles, and the bounding mountain-ranges attain a height of 5,000 to 6,700 ft. It is probable that a dam would be less costly than a race, and it would certainly be much more reliable. Data can be got for this scheme when the other is being investigated. The tunnel would likely be at a different level in each scheme, and if the first scheme were undertaken it would be advisable to put the tunnel at the proper level if the reinforcement scheme is feasible. The power-station at Jollies Pass would be about eighty miles from Christchurch, and the trans-mission-line would serve all North Canterbury. This scheme may prove better than one at Coleridge ; and if a good scheme can be got at Opihi the two would command all the country from Waitaki to the Conway. Opposite the Conway the Clarence is about 2,150 ft. above the sea. It might be possible to get a very good fall by diverting the Clarence into the Conway. So far as I can ascertain from the plans of the Waiau-Kaikoura Road, there is about 1,050 ft. of fall between the road-crossing of the Conway and a point in the Clarence opposite. The distance is about seven miles and a half. How much of this fall could be utilised by a tunnel and conduit along the slopes of the Conway Valley to a point near the road or lower down the Conway can only be determined by an examination. The scheme would appear to be one that might give a large amount of power—loo,ooo b.h.p. or over. Within about thirty-six miles of its mouth the Clarence River doubles on itself, while the fall is great. Tunnels could be driven between points on the river in three alternative places as shown, giving, say, about 800 ft. fall in the first, 650 ft. in the second, and 430 ft. in the third ; while a tunnel to the sea in the fourth instance should give a very considerable fall, perhaps 400 ft. or more. Taking for the present a uniform slope in the river-channel, each of these four schemes would give a large amount of power. How much, and which is best, can only be determined by survey. Of course, only one of the three could be carried out. As taking water from Upper Clarence through Jollies Pass appears to give a higher fall than any of the other four schemes, that scheme could be carried out, and the remainder of the water used in whichever of the other schemes was thought best at any future time. Nelson. Some preliminary information has been got regarding the rivers and lakes in the Nelson District, but it is not yet very complete in any case. The Maitai River, flowing through the Town of Nelson itself, is a small stream. It has a high fall per mile, 60 ft. to 80 ft. The low-water flow is small —said to be 15 to 20 cubic feet per second in the upper reaches, where water would have to be taken from. With a long race only a small amount of power would be obtained. This might be increased if a reservoir of some size could be got. Any scheme without storage in the Maitai is likely to be considerably under 1,000 b.h.p.

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