WAIKATO RIVER BOARD'S OPERATIONS.

Pukekohe & Waiuku Times, Volume 4, Issue 97, 18 October 1915, Page 1

WAIKATO RIVER BOARD'S OPERATIONS.

Progress of the Works. Success in SightFor the purpose of observing the works carried out and in progress on tbe lower reaches of tfce Waikato river, at the instance of the River Board, a visit of inspection to the scene of oparations was tbi3 week paid by a representative of the "Pukikohe Times." MR GLASS' CONFIDENCE

The vicissitudes experienced by tbe Kiver Board need only be briefly referred to as the Bame are fairly well known. Finances have never been ov. r-flourishing, due to (be Government's reluctance to make any substantial contribution towards tbe undei taking embarked on by the Board as a result of the official expert's advice that the lowering of the river was practically impossible. However, Mr A. G. C. Glasj, the Board's chairman, has been a real battler all through, and backed by the opinion of the Board's Advisory Engineer, viz., Mr C. D. Kennedy, he has succeeded in taking in hand, despite all obstacles, the initial stages of a scheme «f momentous concern to the owners ot swamp lands adjoining the river, and judging by present prospects the works designed by Mr Kennedy have every prospect of success. Mr Kennedy, it m&y be mentoned, is a recognised authority in tbe particular brancb of engineering required for tbe purpose, and bis present appointments include those of engineer to the Hawke's Bay River Trust, tbe Napier Harbour Beard and the Hawke's Bay County Council. Mr Kennedy's objective simply is to bring about the reclamation of many thousands oi acres of Bwamp lands from Huntly down the river towards the Waikato Heads by lowering the level of ths water of' the Waikhto river. LIMITING THE RIVER To accomplish this desirable climax the free and unrestricted running of the current cut to sea is the Engineer's aim. Ihe broad and sweeping nature of the river has hitherto impeded the flow of water and scour, and for tbe purpose of inducing the river to follow a main channel instead ff taking intermittent courses and devious routes gtoyncs have been constructed in the lower reaches, while blasting operations are at present in lull swing to ensure the passage of water through a channel of adequate depth at the junction of the river and Maiora Bay—about three miles from the heads and 16 miles from Tuakau—in place of the flow beirg restricted by having to pats over a sand bank that constitutes a shallow bar. WILLOWS AN ASSET The writer was conveyed down the river from tbe landing stage at Tuakau oa tbe River Board's launch the "Mascotte." At different points workmen employed by or on behalf of the Board were to be seen busily employed in tree felling either for the purpose of eecuring posts to be utilised as piles or for the collection of willow barrels and branches for deposit between the piles to constitute the groytes. Incidentally it may be mentioned that tbe willows form a picture of rare beauty all along the river, and it is interesting to remember that they are essentially self-sown. In tbe early days some were planted bv tbe missionaries on the river banks in the vicinity of Ngaruawahia, and drifts of branches therefrom, aided in many cases by additional planting by the natives who admired that particular form of forestry, have been responsible for tbe continuous line ot willows that now adorn both sides of the river. FIXING THE GROYNES

At the Devil's Elbow, un the Raglan Fide of the river, some seven miles from Tuakau, is the first section of groynes, the same being about two miles in length. Files have been driven in and willow branches laid between them, the latter being simply a form of fascming. The vitality of the willows is such that they grow under all conditions and shoots even spriag out from apparently dead barrels. Branches brought down with the flood last winter have for instance found a lodging place amid some of the piles and are to be seen in a forward state of maturity. But for the wonderful • vitality of the willows and their capability of acting as a dam for tbe water, tbe expense that would have been entailed in restricting the course of the river would have betn prohibitive and the scheme tor narrowing the bed of the river would necessarily on that score have been a failure. However, Mr Kennedy was far-seeing, and utilisation cf the willows formed a most important point in bis calculations. In due time as the result of the natural growth of the willows, with their roots seeking the soil and at the same time the tendrils springing upwards, it ia confidently anticipated that the outer area of the groyne will become dry land and that accordingly the channel or course of the river will be restricted to dimensions that it is possible to coutrol. If that is brought about numerous islands on tbe river of present little worth will become attached to the mainland and will form ideal grazing grounds. These islands, as also the backwaters that run around them, are now j from a scenic point of view a

great feature of the river, tut utility, rather ttian spectacular effect, must be considered, ard the Kiver Board in transforming insular territory into areas connected with holdings of access ire catering tor the public welfare rath er than for toutist or sightseeing demands. Further down on the opposite side of tha river, viz., near the Aka Aka inlet, is another set of gmynes extending for a mile is distance. In either instance the efficiency of the groynes in formiog a bulwark and thus a bank for tbe water is already noticeable although the willows are only juet commencing to put forth their growth. On the inner (or river) side of the groynes the stream sweepi meriily along whilst on the portion shut off, i.e., the backwaters or side courses, jittlc or no current is observable. Again, between Kaitangata and Maiora Bay similar groyning ' work is in course of prguress and a length of seme two miles will, it is expected, be thus completed about three weeks hetcp, the steam pile-driver being actively and constantly engaged in the operation. BLASIING A CHANNEL The groynes having already'to a certain extent accomplished their object, or at least having given indications that in due ccurse they will fulfil requirements, the task of expediting tbe passsge of the flow of water over tbe taaioia Bay "bar," previously mentioned, is being embarked on and tbe same constitutes practically the most vital portion of the problem of lowering the river by forcing the water out to sea. On the sand bank in question the greatest depth of a very restricted channel at low water has been eighteen inches, and at high water not more than six feet for a distance of halt-a-mile, the river itself at high water being about four miles wide from bank to bank, the greater part of wbieb, however, becomes more or less dry land at lon water. A straight channel for the half.mile over the sand bank has been marked off and blasting operations thereon are being vigorously resorted to. Tbe explosive used is call:d "Eruptite," the same being particularly powerful for use under water. As tbe tide runs out a harrow, drawn by a launch, is brought into use, and the loosened sard is thus carried away to sea by the current. The most tatisfaclory feature of the proceedings—and indeed a highly important pointis that tbe incoming tide does not bring the sand back and thus there is no difficulty in keeping the waterway clear to the depth and extent secured by tbe blasting and harrowing. Ptior to the work beiftx started the depth at low water of the particular line of cha:nel receiving attention was only six ir.ches, but at the time of the writer's visit thi3 had been increase 3to nea'ly three feet and work will not be buspended until a depth of at least seven feet at low water has been provided on the channel, which is to be 25 feet wide, fur tne halfmile stretch, deep water then being encountered right away out to see. THE OUTLOOK BRIGHT Owners of land in the upper portion of the river found to their satisfaction last winter that Hood waters disappeared more rapidly than was previously the case, and Mr Kennedy's prediction that the construction of the groynes on the two sections, Tuakau bridge to Kaitsngata and Kaitangata to Maiora Bay, together with the provision of a channel leading into Maiora Bay, would, when everything is in thorough working order bring about a tall of the river of at least three feet at Mercer has every indication of being realised. Mr Glass, as chairman of the Fiver Board, is naturally considerably elated at the successful progress of operations and t e remedial effects already stcuied, and he pays a warm tribute of appreciation to the Board's employees for tbeir ready and loyal co-operation, Mr P. Sellars, the Foreman tf WtrkJ, particularly coming in for commendation not only for his skill in carrying out tbe enigneer's plans, but for his assiduous attention to duty at all times and occasions.