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Press, Volume LXXIX, Issue 23948, 15 May 1943, Page 4

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ASHBURTONHINDS .FARMERS REPLY BY IRRIGATION ENGINEER The announcement of the Government's intention to push ahead with the completion of the Rangitata divetsion ?acs so that the Highbank power station can begin generation wm ter has again raised , th ! ;rtonage among farmers in the Ashburton Hinds drainage area. Mr R. D. Robinson, president of the Ashburton County Irrigation Problems Association, to d a reporter of ‘•The Press” that a meeting of the association would have to b held to consider the position, althoug he personally was prepared to lay a substantial bet that the watei not be flowing into Highbank for m other two years. attitude Mr Robinson explained the attitude of farmers in this a. 1 . 03 ., 10 tion scheme, and said they coul =ee how substantial seepage could be avoided from the big channel running for 40 miles of its course throuji shingle formations. The views of Mr J O. Riddell, irrigation enß m ««^ f ?£ fanterburv who recently returnee fake charge of this job, were also obtained on the question of seepage. He said there was no cause foi aim m. Saving that farmers on the best coun trv in the Ashburton County wanted «?e Government to gel the "dvnce of an expert from overseas before the scheme was finished, Mr Robmson sa d the Government had only * firieahlame if farmers opposed the mrig tion scheme. If the Public Works Department had made a success of the ravels scheme, thcie would be n P position, but they had seen the seepag at Seadown, and they fcal n cd (h p-f n l „, n same thing might ha PP^ r^v th a ei , l ve °« e " HUtrict which was naturally a weuei d Strict than seadown. Although the drainage system at Seadowij was not finished, sections of it wcit, and . land was still wet. Report oi. American Schemes Mr Robinson said seepage could ’JA hn avoided in an irrigation scheme. He Quoted the following extracts from a report made in 1914 by a South Afncan exnert Mr A. D. Lewis, on irngatkmUnited Stales: "From Amorican exoerience we .learn that dra age works. h a ve become a necessary^ on often where least expected. .’ . . In the original estimate of expenditure for a scheme, it is fore advisable to anticipate tha, a^cer S^e^^fnd^wm^^'ufrr'dS^e rcr? 5 measures ffl 5 €tes [mned Into the diversion race il _ « X in C «el.%lleVb'Sl la . r he h cos; would be very great. He <aid there had already been seep a small race at the experimental farm That channel had been m L t u een years, but the department had not bee able to stop the scep a ge. q{ the fSSiis Mr Robinson said somefaimers not seem in favour of the senemu cost of which would be divided beseenage the Government would not b fble to say that they had not taken ad Mt n Eo e bin°son l questioned whether the S heavily on them. The "venue from the Levels scheme loi the year ending in the winter of 1941 had been only £844, which was commonly sup posed to be much below the operating cost, without capital charges, A postal ballot of farmers between the Hinds and Ashburton rivers, from the sea to the diversion race, had shown a majority of 70 per cent, against irrigation, said Mr Robinson. _ They did not want to deny anyone irftgation but they wanted to protect their land. . Engineer’s Opinion Mr Riddell said the Public Works Department had always said there would be seepage from the channel in the first year after its construction, but this would gradually decrease as the race became sealed with silt from the Rangitata, till it would not be of consequence at the end of four or five years. The position at Seadown was improving and it had to be remembered that the Opihi river, from which the water was taken, did not carry nearly as much silt as the Rangitata. Before water was turned into the Rangitata race the channel would be conditioned with clay to check seepage It would not be necessary to concrete the Rangitata race because the puddling now being done and sill would seal it sufficiently. It could not be compared with diversion channels in the United States, where the rivers carried comparatively little silt. Mr Riddell showed the reporter the section of the race where seepage had occurred. Puddling work with stiff clay was in progress, and Mr Riddell said that already the loss of water from the race had been very much reduced. He said that in the other case mentioned by Mr Robinson the bank of a channel constructed in a hurry had been built along a road, and in some parts it was on top of the metal. Water had naturally seeped through here. Be. cause the trouble was not serious the department had not taken steps to stop it, Mr Riddell said the seepage arguments had been raised years ago when the county stock race system was constructed, but no opposition to that was heard now, Answering suggestions that the work was not economic. Mr Riddell said that, if farmers used the quantity of water that they could profitably -use, the scheme would pay for itself, capital as well as maintenance. Eveh if there were some slight direct loss it would be more than made up by the indirect benefit from 'increased production. The full revenue of a scheme was not earned .immediately because it took some time for farmers to realise the benefits. However, the results obtained at the experimental farm and the low ! charge for the water, which as far as j he knew was as low as any in the world, would encourage them to make use of the supply. ] The advantage of the Rangitata 1 scheme over irrigation schemes in other j parts of the world was that there was | no expense in providing storage. The i cost would be higher than was at first thought, but that was compensated for to some extent by the development of the Highbank power station, which was an afterthought.