RIVER CONTROL

Manawatu Herald, Volume XLVII, Issue 2872, 18 April 1925, Page 2

RIVER CONTROL

MODIFIED SCHEME SUBMITTED. A scheme designed to give the Mariawatu and Oroua Rivers the best channels to the sea, to remove flood menace, and improve thedraii ago of (he whole district, lias for some time past occupied the attention of the Mnnawatu-Oroua River Board, and it was estimated the cost of such work would be £435000. However, the limit that the kind.-, within the Board’s area can alford to pay for the benefits derivable from such a scheme is £250,600, and without outside assistance this proposal cannot he put forward as a business proposition.

At Friday's meeting of the Board held in Palmerston N._, Mr F. C. Hay submitted as an alternative a modified scheme designed to deal with floods up to about 17 feet on tin Fil/.herbert Street gauge, plus a medium Hood in the Oroua River, The c-ost was estimated at £174,000. This modified scheme is designed to control such a"flood as the above within defined limits. These limits, it was stated, were such that later mi improvements could he effected within them and further steps taken io attain the complete .scheme of river control, without abandoning or rendering obsolete any of the works included in the modified scheme. It. was estimated that floods up to 17 feet on the Fitzherhert gauge did not occur more frequently than once in every ten years, or ten times in a century.

Included in the original scheme, in addition to the levees and cuts required was the purchase of land and the building of bridges. In detailing the scheme, the engineer put forward the cost of necessary works to effect the scheme, such as snagging the lower channel of the Oroua £BOO, excavation for levees 2,000,000 yards at Is Cd, £150,000; culverts, floodgates, etc., £3,200; diversion cuts and purchase of several areas £6,000; flowage rights, £9,000; total, £174,000. Item four of the above was not absolutely essential, and could he omittd d' the price put on the land was unreasonable. With regard to flowage rights, wherever the limit of the carrying capacity of the river channel was reached, spillways to take the surplus waters were provided. The first was at the end of Hamilton road on the right hank of the Manawatu, and began to operate. when floods reached 14 teet on the Eitzherhert gauge. Under present conditions the land on which the spillway was proposed flooded when the river reached 13 feet on the gauge. The land would thereIVre he less affected by floods under the proposal —even though if was a spillway —than it was now. It was estimated that floods would operate, given this spillway, twice in three years on the average, and then only for a few hours. After passage of' flood the umvatering of the lower portion would he carried out by a 3 foul culvert. The area ilint would he affected in the direct jinth of flood waters was 76 acres; ilie whole area Eof spillway lever io the river bank was 256 acres. From tho above, the engineer considered that flowage rights would lie obtained for nothing. The next place where flowage rights were required on the right hank was at Rangitane, when 33 acres of land floodable at present were required for spillway purposes. The same remarks applied to this place as to the previous one. and the engineer considered that compensation here for flowage lights would also be nil.

()n the right bank opposite Kangitane an area of 171 acres would be used as a spillway. Of ibis area, 113 acres were already Ihiodable, and would be less Hooded under the improved conditions of the river channel. Flowage lights would he nil. The balance of 58 acres was protected now by the Makerua levee, and compensation would he payable on this area. Mr Hay estimated the flowage rights at £5 an acre, or £'2!)(l. Of West mere, (!4 acres would lie left within levees and utilised for the passage of flood waters. All the rest would he fully protected. It was now flooded at 13ft. bin. on the Fitzherbert gauge, and would not be flooded under the improved conditions till about 14ft. Gin. Compensation for flowage rights was estimated at nil. The by spillway at Moutoa contained within levees 1,G22 acres; the lower portion was now (loadable at 9ft. on the gauge, and the upper portion at about 12 ft. Under the new conditions the area within the levees would flood at about 10 feet on the gauge. Provision had been made for unwatering the lower portion of the area after floods had subsided. There were low-lying swampy lands in part of this spillway which would get a. rich deposit of silt and be improved. Flowage rights as a whole were estimated as worth £3,110, and in round figures £9,000 had been included in the estimates for this item. It would be noticed that this scheme did not include cuts through the Rush Elat, or Manawatu Kuku. No bridges were required. Transport facilities were, if anything, improved under the scheme, though Shannon Road and the YYhii okino road would be occasionally (flocked.

The engineer went into further details of the scheme with a map. Mr Gower asked if this modified scheme or the other was to be presented to the ratepayers. Another member said that Mr Hay was merely submitting the modified scheme to the Board.

The chairman remarked that it was all a matter of expenses, and that if the Government would render its assistance, a definite Step could be taken. The engineer said that if it came to a choice between the two schemes it would lie cheaper now, to go on with the complete one. It was for the Board to decide whether to proceed with the latter, or to leave the completion of the scheme to posterity. Although the modified scheme and its extension would cost more than the other in total, there were nevertheless undoubted benefits to lie gained from its employment. Various aspects of the scheme were then discussed. f l’he chairman stated that the Board had got to that stage now where it had to decide what its future was to contain, whether an endeavour to solicit the aid of the Government in the Dig scheme, or io start a small one as a preliminary. Air McDonald said that the Board was now in a quandry owing to the lack of support that had been accorded the big scheme, and he thought it was now impossible |o carry on with it. The ratepayers were very much opposed to it, and the Board had now either to submit to them something that would i ost less than the oxiginal, or throw up the whole thing. He certainly iiid not favour the latter course, but thought the modified scheme before the Board a very good idea, and thought that it should be given further consideration. Ii was decided to defer consideration of the scheme until next nu eting.