THE WAIMAKARIRI.

Press, Volume LXIII, Issue 18891, 5 January 1927, Page 8

THE WAIMAKARIRI.

TO THI SDITO* Of THI PBISS. Sir _I wish to thank Mr George Gould for the information he has given in response to ray query. It is nonclear that he believes in a scheme in accord with that of the Trust's, but in a modified form, hut it would be better if some data could be given to show that a modified and less costly scheme could be made a success. There is a danger that a smaller and less costly scheme may be the more costly in the long run. Mr Gould considers that the Trust is making provision for unnecessary width, and that the cut should be narrow, deen, and swift. All things being favourable, as a layman I quite agree with that opinion, so far as its being narrow, deep, and swift is concerned, but it appears to me that there are two important factors that militate against giving successful effect to such a cut at this particular place. One, that it is not of sufficient height above high-water springs to allow the bed to be made deep, and two, the loamy formation would make high banks difficult to maintain, thus making width an essential to get a channel that can be held. It also appeared to me that it would not be correct to make the bed narrower at this place than at any other point of the river.. Would it not be a bottle-neck and have the effect of causing the moving shingle to deposit and raise the bed above the neck, as Mr Gould says it is now doing above the bottle-neck at the creamery site on Ccutts Island? How the scheme is likely to operate can be judged by the facts that the deck of White's bridge, which is five miles from the present mouth ; is only 17 feet above high-water springs, whereas the top of the stopbanks of the new course, five miles from the mouth, will be 32 feet above higl>-water springs, which is equal to, at that distance from the mouth, as if White's bridge were fifteen feet higher than it now is, which means a great increase in the scouring force of the river near the mouth, and I believe it will be found that the new gradient of the bod for that distance will be similar to that of the Ashley, which discharges its gravel right out to sea. The objective of the Trust in endeavouring to prevent erosions on the banks and of making the river clear its own course is to be commended. Some doubt is expressed as to whether it will deliver the shingle out to sea. Should it deposit it near the mouth, will not dredging at that place be a simpler matter than having to do that operation the whole of the _ ten or twelve miles up the river, as indicated by Mr George Lee.—Yours, etc., HENRY H. HOLLAND.