HYDRO-ELECTRIC WORKS.

Taranaki Daily News, 9 August 1921, Page 5

HYDRO-ELECTRIC WORKS.

NO. 2 TUNNEL SCHEME. NOT TO BE ENLARGED. DECISION ON THE COUNCIL. Discussion on the No. 2 tunnel scheme by tie New Plymouth Borough Council reached finality at last night’s meeting, when a resolution in favor of driving the tunnel on the larger scale—a course which, it had been suggested, would leave the way open for power development in the future —was rejected. In response to a request made by the council, the resident engineer (Mr R. L. Pearless) submitted the following figures on the expenditure at the works: Total cost of driving No. 2 tunnel to date, £Bl4 5s 9d; total distance driven, 424 feet; cost per lineal foot driven, SBa 6d; total number of cubic yards removed in driving tunnel, 1017; cost per cubic yard removed, 16s.

Continuing, the report stated: With regard to the driving of the tunnel at an enlarged size, I have to point out an apparent anomaly, namely, that the actual driving which is taken as a separate cost, remains identical for both sizes. The enlargement is apparent only when dealing with the trimming prior to placing concrete, and *for the purpose of comparison 1 ftm allowing a 50 per cent, reduction in cost of trimming for smaller size as against the actual trimming done and costed to date, this latter being for larger sizd. Further, in regard to this question, it is necessary to point out that it can only be given on the assumption that rhe material to be passed through will of the same or better nature: also, it is assumed that there will be no further delays. I have on several occasions pointed out that the work done to date has been frequently hampered; moreover. there seems to bo no consideration for the time required to be spent by me in getting out frequent costs and reports. travelling on road, instead of using telephone, all of which, could be more profitably spent on the acsuai works in checking and preventing leakages that may occur, and which can only be dealt with personally. As to the cost of driving the enlarged tunnel, the report stated this would remain the same. At the price, 38s fld per lineal foot, this represented a saving over the original estimates of £2700. The additional cost for the large size was given at £4493 ss, and deducting the saving (for driving) of £2700 on the original estimate, there remained £1793 5s as additional estimates to carry out the tunnel at the larger size, compared with the original estimate for the smaller tunnel. Comm ing on the figures, Mr. Pearless stated: My original costs were made up to include all material purchased, with the idea of the works being closed down. It is obviously unfair to charge the cost of all material to the small portion of the tunnel completed. OPPONENTS OF SCHEME. When the discussion on the report was opened, Cr. R. L. Parkin pointed out that in addition to the cost mentioned by the engineer there would be an expenditure of £341)0 for the forebay and work outside the tunnel. In reply to the Mayor (Mr. F. E. Wilson), the general manager (Mr. F. T. Bellringer) said that the original motion before the council in the names of Crs. Rumball and large, was that the i tunnel be enlarged throughout its length. Cr. Parkin said he was sorry he could not support the resolution. After some consideration he had come to the, conclusion that the extra work was not warranted. The tunnel had been designed in connection with a 9000 h.p. scheme, and taking the minimum flow of the Waiwakaiho as 150 cusecs, it would mean they would have to divert j

; two more • Waiwakaihos to fill it. Personally he did not think there was any chance. of getting water to this extent. As a matter of fact, the minimum flow of the rivet was not 150—it was down, to 90 last year. The electrical engineer (Mr. R. HBartley) said this was an exceptional happening, and had occurred only once in his six and a half years’ experience of the river. Cr. J. Kibby said Cr. Purkin had pointed out the weak spot. The capacity of ihe small tunnel was 450 cusec*; the council had been talking a long whiff* about 150 being the minimum of the Waiwakaiho, and the tunnel pro- | vidcd for three times that.. He had been i strongly in favor of the big tunnel, but j he could not see why the council should I spend £l7OO more on the tunnel and practically £3500 on the outside, when they would require more than three times the present flow of water to uae the tunnel. Mr. Bartley said the question did not so much concern the fact • that they would need a bigger flow of water. The tunnel would be used for carrying water out of a reservoir. DUTY TO THE FUTURE. Cr. T. N. Blackhall said he still believed that while the council were spending an enormous amount of money on the work, it was their duty to finish it, not for the present day, but for the future. He believed that the town was on the advance, and as it grew more and more power would be required. There were rivers adjacent to the Waiwakaiho which would provide A big supply of water, and though this might not be needed in the present cuunciFg term, they should have a tunnel which would carry the water. He thought It would be a wise policy to increase the tunnel to a large size. It had been said that in the near future it would pay to put in another tunnel, but he considered there was no room for another tunnel. Cr. J. Brown said he was quite prepared to support the larger tunnel scheme if he could be assured that the council would not have to spend money on outside works, because in his opinion it was not going to bo necessary for some years. The Mayor said the engineer had given the\ opinion that the work on the forebay should be undertaken in conjunction with the enlarging of the tunnel. if this was agreed on. Cr. Blackball said he was confident that the forebay was not required at the present time, even if the tunnel was enlarged. The Mayor said it was peculiar to hear councillors seize on an engineer’s opinion when, it suited them, and differing from it when it did not suit. If one thing had been made clear by Mr. Owen (one of the consulting engineers) it was that he would not recommend them to do the forebay separately. Mr. Wilson said he was still going to vote against the motion, fnr reasons already advanced. There was one point to be borne in mind: Unless the council could produce hydro-electric power at a certain figure it would not pay. The increased tunnel would not be wanted in the next decade; possibily not within the next fifteen /years, and by that time the council would be able to buy power from the Government if any was required above the 9000 which would be provided for in the complete scheme. The resolution was lost, th* only ayes being Crs. Rumball, Large, and Blackball.

The Mayor said that as it had been urged that the council would be misleading Mr. Leggatt in entering into negotiations without enlarging the tunnel. ho desired to move Hint a cable bo -ent to Mr. Leggatt advising him that the council was not enlarging the tunnel beyond the original designed by the engineer to provide up to 9000 h.p. The resolution was lost, the council being of opinion it was not necessary, the position having been already mado sufficiently clear. THE DEMAND FOR POWER. The general manager, in his monthly report, made the following reference to scheme E2: Since the flotation of the loan was arranged I have taken up with the electrical engineer the question of whether sufficient electrical machinery is on order to enable the council as soon as scheme E2 is completed, to cope with the. increased demand for power in the town, and also in th® Stratford and Eltham district.

After dealing with technical matters relating to plant, the engineer’s report mentioned, stated that when certain alterations were carried out the station output would be brought up to 3000 h.p., and in addition to this the machines would have an overload of 25 per cent, for two hours. He said that a tender of £1630 had been received in August, 1920, for certain materials in connection with the alteration to the plant, and he thought these figures should show a substantial reduction at present. It would only be necessary for this material to arrive within the next twelve to fifteen months, and this amount could then be met out of revc» nue, as allowed for in the estimate?*.

The engineer’s report, concluding, stated: “We must, however, bear in mind that if the proposed power district is not formed, or if they do not purchase their power from us, that it will not be necessary for us to make the alterations for some time yet. On the other hand, should the power be purchased from our works, the demand will be gradual, and it should he an easy matter for us to increase our plant with the demand.** Commenting on this report, the ernl manager continued: There is one. portion of the report tn which 1 must direct special attention, viz, to the statement that the cost of altering the various machines, totalling anything up to £5OOO, being spread over a mparatively long period, can be met out of revenue as allowed for in the estimates. The estimates foi‘ the electrical plant do not show that such estimates are not complete or that, substantia! item# have been left out to he provided for The same position arose in Novcmbet of last year. A few days before thi poll, when preparing a. statement to ba placed before the ratepayers. 1 discovered that items totalling some £20,000 had been omitted from the estimates for the same reason. These two items mean that within a few years the department will have to provide some £25.000 from revenue, and this in lean years before the borough l is able to get back into a good financial position. It would have been much better if the estimates had disclosed the whole position. The council would then have been in a position to have judged the matter from" the financial point of view of the whole borough, and not from the point of view of one department. As it is. considerable difficulty must be ex* pected in financing the, expenditure when the time comes for ‘the expenditure to be