WATER POWER AND ELECTRICITY.

New Zealand Herald, Volume XLI, Issue 12699, 31 October 1904, Page 6

WATER POWER AND ELECTRICITY.

POSSIBILITIES OF NEW ZEALAND RIVERS. MR. L. M. HANCOCK'S REPORT. SITES IN THE AUCKLAND DISTRICT. [IIY TETjKGHA.I'II.SPECIAL , C'ORRESFOifDEXT. ] Wellington*. a today. The report of Mr. L. M. Hancock, the American electrical expert, who visited New Zealand a year ago for the purpose of reporting upon the value of the rivers of the colony in regard to the generation of electrical power, was laid upon the table of the House early this morning. The following references to locations in the Auckland district are made .in the report: — THE WAIRUA FALLS. Reporting on the Wuinia Falls, Mr. Hancock says that the locality lias the greatadvantage of being the nearest to the great industrial centre of Auckland. Surveys were nob complete, so that the total possibilities could not be fixed. The locality made a great impression regarding its possibilities, and is well worth a complete survey. Mr. Hancock goes on to say:—"l have used only a head of 150 feet in the calculations, but if the surveys show it is possible and I. think it —a dam 30 feet to 50 feet high can be built, giving the benefits of storage and increasing the possible development. This depends somewhat on what can be done with the waters of the Ma-ngakalua. If they can bo directed into this ■■ reservoir the possibilities w ill be increased. The main disadvantage under which this locality labours is that it is j somewhat remote, and that machinery and J material will have to be handed several i times. This, however, is not prohibitive, J Ouo great advantage is the presence of the cement works, near Whangacei, which can. supply an excellent grade of cement, and also utilise a good deal of power when the plant is in operation. I would recommend that complete surveys be made here as soon as • possible. I would also suggest that records be kept of the rainfall, snowfall (if any), heights of streams, and frequency anforce of thunderstorms for the district." THE OIvERE FALLS. Reporting on the Olcere Falls, Mr. Hancock says: "These falls themselves are of no greatvalue for power purposes, but the total droo in the river in a distance of a trifle less than a mile gives an availably head of 101 feet. This, with a dam which should raise the height of Lake Rotoiti five feet-, will give a .total of 106 feet maximum, and a storage that will 'be of exceeding (Treat benefit in cases of drought fact, the storage secured oy raising the level of the lakes as suggested will be sufficient to maintain the flow of 500 feet per second for 91 days. The rainfall for this region, as recorded at Rotorua, in about 50 inches per year, and the precipitation is well distributed over the entire year. The location is 13 miles from Rotorua, the terminus of the railroad, so that transportation would not be. a serious item against it. '.the distance iirom Auckland (153 miles) is the most unfavourable condition. The maps and surveys furnished me of the falis district ?rs not- complete enough to make any complete) estimate of the cost- of the: plant. In order to decide whether this location can be developed to advantage it. would be necessary to know whether the level of the lakes can be raised, and how much., for storage purposes. To determine this contours will have to be run wherever the laud is considered valuable. If the amount of power listed can be developed' here without too great expense it will be better than the powers in the Wai- | kato for the initial development to supply i Auckland district, for two reasons at least.. It is 25 miles nearer, and transportation from the railroad is not nearly so e r-"--I would suggest that more complete records be kept of the heights of the lake and streams, and of thunderstorms for this district. The rainfall for this watershed is not accurately known, though at Taupo township it is recorded 3,s 50 inches.

THE UPPER WAIKATO. Speaking of the pow»r locations of the Upper Waikato, Mr. Hancock says: — "This is the largest river, and its drainage area of 5500 square miles the largest of any stream in the North Island. It not only drains very high bush-clad country, but also has Lake Taupo as an enormous equaliser, and its variations should be very gradual. . ATIAMURI RAPIDS. To utilise power at '.lie Atiamuri Rapids there would need a da::a to raise the water level iiU feet or 30 feel;, according to what the benefit would be. This probaolv is not the best place to put in the initial envelopments, but it is certainly a valuable location. Before anything further can be stated as to the possibilities or cost, surveys will have to be made. I would suggest that the rainfall, heights of the river, and thunderstorms be observed here, and records kept, 30 that .ill the data possible will be available, THE RAINBOW FALLS. The .Rainbow 'Falhi, situated only about three miles and a-ha-if above the Atiamuri Rapids, need only a small dam to con . trol the flow. There have been no surveys here, and it is more than probable that conditions will not warrant their being made for some time to come, unless conditions at other- places do not turn out as flattering as is anticipated. . ORAKEIKORAKO GORGE. The gorge below Orakeikorako is next referred to. The report "says: The Waikato at this place has cut. through the high ground, and made its * way between very high vertical walls. This is about three or four miles after the Rainbow Falls, and appears to be of such a formation that a very high dam could be built. It may bo possible, by the construction of a dam here, to divert the water into a race to carry it past the Rainbow Falls, and utilise the dron th a in combination with that created by the dam. The appearance of the country does not encourage this view, however. A survey will show what is possible. The cost, of this scheme would be excessive on account of the great quantity of water to be handled, and the high dam necessary. I do not think it is necessary to spend, any time or! money oil this location now. ORAKEIKORAKO RAPIDS. Referring to the* Orakeikorako Rapid's, the report says—Apparently great energy is wasting there, but it. is not in a favourable location to lie developed, and has not advantages enough in its favour to warr;„;'i any investigation. At present the head is very much less than at Rainbow Falls, and the banks of the stream are not nearly so favourable for a dam. It would be extremely costly to develop. THE AR AIT ATA RAPIDS. Of the Aratiatio Rapids, situated it the Wails ato, a jout four miles below the .lluka Falls, the report saj s: —Tl:i<i is at once tJuj> most beautiful and most valuable potter local-ion on the river. In many respects tin rapids aw more beautiful than the. falls, which car toast ol' only one advantage, that of the possibility of a. small data controlling the outflow of Taupo. Thire is stch a slight grade between, the falls and tie rapid;i that it is possible to, bund only a 101't dim at the 1 ead of the rafiids without- flooding tie falls. This liitijts the energy available.; it the rapids to 56.-JOO horse -power, obtained by mean j of a fill oi 110 ft. The.only place at present to • which it seems 'vise to. transmit jpewer from this district is Auckland and its .suburbs. Complete str-veys will have tc be made before any estimate can • be made of the cost of. its development. This location .shows, with Huka, the disadvantage of considerable distance from the railroad, hence a large expense would be incurred in transporting machinery and material. THE HUKA FALLS. The report deals with the Huka Falls I os follows:—This is the most noted power r location of the island, and it is very valu-j

able, but it is not :;o good as the Aratiatia Rapids, and will be even more expensive to develop. It is a beautiful spot, and justly attracts a great deal of attention. The development of this locality would be quite expensive, on account of the low head and the heavy excavations necessary for the power-house. What was" said in regard to Aratiatia applies here with equal force. It does not seem wise to transmit energy from this district at present, on account o- the expense. The rainfall for this watershed is only recorded for the Taupo township, I would therefore suggest that plans be made to get records for as high altitudes in this district as is possible. 1 think you will have no trouble in getting some of the stations to record them as well as the height of the lakes and rivers, and the frequency and force of thunderstorms. " It would be especially advisable to secure records of the height of Taupo each day during the- year. In view of the fact that a dam at Huka will submerge some geysers near the Spa, it will be wise to have some experiments carried out with the local geysers to find what degree of activity they will maintain when submerged by a given depth of water; also what temperatures are maintained, and at what temperature action commences, and whether, when a great quantity of cold water is over them, they will become a leak. ROTO AIR A. Tills little lake of six square miles, nestled away in the high ground above Lak«) Taupo, is worthy of some attention. The inflow is limited, and the natural drainage area very small. The distance and the limited amount of power available with small expense do not seem to' justify any surveys at present. It would be advisable, however, to gather what information is possible m regard to rainfall, snowfall, height of the lake and river, 'id storm data for future reference.