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APPENDIX IV.—RIVER PROTECTIVE WORKS, LINDSAY SETTLEMENT, HAWKE'S BAY LAND DISTRICT.

[By H. Martin Smith, Crown Lands Ranger.] Before entering into details in oonnection with the above, it might be well to mention that the position of these works is about seven miles distant from Waipawa Township and Railway-station, on the right bank of the Waipawa River, which forms the boundary between the Argyll Settlement on the north and the Lindsay Settlement on the south. The latter, formerly known as Mount Vernon Estate, was purchased by the Government, and opened for settlement on the llth April, L 905. Previous to the purchase the former owner expended considerable sums at various tunes in endeavouring to confine the flood-waters of the Waipawa River within reasonable limits, and prevent the flood-water from connecting with the Waipawa-Mate Stream and thence on to the Tukituki River, into which their is a considerable natural fall from the Waipawa River. Should such a oontingenoy arise it would mean the destruction of thousands of acres of rich alluvial flats, .Hid would lie very disastrous to the district generally, and the Township of Waipukurau would suffer very materially. Since the purchase of Lindsay by the Government, the late Roads Department spent some thousands of pounds in the erection of protective banks and the building of groins. Subsequently a number of the latter were washed away, or buried up, and the river made such serious encroachments into the protective bank as to render a considerable amount of the work useless, threatening to force its way behind the works and wash them away bodily. On the 25th August, 1909, a sum of money was authorized to be expended under the control of the Lands and Survey Department in repairs, and I was instructed to undertake the supervision of the work. Drawings and specifications were supplied by Mr. Brodrick, who was then Chief Surveyor ami Commissioner of Crown Lands at Napier. His scheme, which I understand proved very successful when tried on rivei-banks in the South Island, has, I venture to say, in this case been the most successful of any work of the kind I have seen elsewhere. The principal feature of the scheme is the erection of a substantial fence with piles at each end firmly driven into (he shingle, and intermediate iron rails (old railway iron) along the fence, which is constructed with No. 8 galvanized wires tightly stretched between the end piles. Stout green willow posts are let down into a trench well below the ordinary water-level, and firmly stapled to (lie wires. Stops constructed with wire netting and filled in with gorse are erected at 1 chain or less intervals, and made to extend back from the fence to the protective bank, and have the effect, where the current is strong or a big body of water to contend with, of breaking tfite force of the water and depositing silt in place of eroding the hank, as would otherwise occur. In all cases before the erection of the fence or bank has been undertaken it has been found necessary to temporarily divert the river by means of sand-bags or sacks filled with shingle. In many instances unexpected floods or local cloud-bursts have washed these away, and delayed the work in some instances for several days. I feel confident, however, that the work is a successful and permanent undertaking, and, although a somewhat costly one, is good value for the money expended by the Lands and Survey Department. The work completed to date comprises 55J chains length of fence with stops, 55J chains length of bank behind fence, 10| chains length of groins 7 ft. by 4 ft. dimensions, sl| chains length of willow fascines, 1A chains length of stop-bank. The above is exclusive of the labour in connection with the turning of the river at various times, time lost through unexpected floods, and repairs to bank and fence seriously damaged by flood in March last year. The total cost of above work to date is about £1,500, although I have been careful not to undertake more work than was absolutely necessary. It is very fortunte that the Under-Secretary for Lands was able to visit the works recently, and during a flood in the river, and thus form an opinion as to the efficacy of the work as completed. There are other places along the river-bank and in the neighbourhood of the present works, although not at present in immediate need of may later on require protecting, and if more money is available it would be of advantage to attend to this. I dcs-ire also to place a great stress on the fact that until the willows have thoroughly established themselves a certain amount of supervision will be necessary, and I would suggest that a certain sum might he set aside for this purpose. It is reasonable to expect that in their own interest the settlers in the neighbourhood will endeavour to prevent the trespass of stock on these works, which would materially check the growth of the willows so essential to the ultimate success or otherwise of the undertaking.