PROTECTION FROM FLOODS.

Manawatu Herald, Volume L, Issue 3910, 23 February 1929, Page 3

PROTECTION FROM FLOODS.

RIVER BOARD'S' MODIFIED SCHEME. LUCID EXPLANATION BY ENGINEER HAY. REMOVES FALSE IMPRESSIONS COUNCIL FAVOURABLY IMPRESSED. Two hours speut last evening in the Council Chambers by the Engineer (Mr. F. C.Hay) in explaining the Manaiwatu-Oroua River Board’s modified scheme of flood protection wonk, will possibly have the result oi; reversing the Foxton Borough Council’s whole attitude towards the proposal. At any rate, Mr. - Hay has the satisfaction of know - ing that after his explanation of the scheme Crs. expressed themselves as being favourably impressed while the Mayor said that he felt' quite sure that at the next meeting of the Council a motion would be passed in favour of the scheme, this being a comlplete reversal of the Council’s previous attitude. Mr. Hay attended a special meeting of the Council last evening to fully explain the scheme on the suggestion of Cr. J. Ross. The Mayor (Mr. M. E. Perxeau) accorded him a welcome and introduced him to Crs. S. E. Cowley, R. J. ThoSmpson, C. Rand, F. Lucinsky, C. Spring, and the Town Clerk (Mr. Wim. Trueman). An apology for absence was received from Cr. M. 11. Walker. DESCRIPTION OF “CUTS.” Mr. Hay, by the aid of a map, explained the modified scheme in detail but dealt more particularly with that portion so vital to Foxton, the Moutoa. Between the Heads and Dr. Walls’ corner, at Marotiri, the Board propose to put in three “cuts,” one across Rush Flat, one across the plateau above Matakarapa and the other from Dr. Walls’ corner to connect up with the other two cuts a little north of the Government Drain adjacent to Mr. F. Woods’ property. This latter cut will embody the Government Drain and will give four foot better draining at the top end than at present obtained with the existing outlet. On either side it will have flood gates at intervals to taJke the drainage. It will be a quarter of a mile wide between the banks, with a “pilot” channel twelve feet deep and forty feet wide in the centre. This pilot channel will actually peter out before it reaches the river again. That cut under the modified scheme, will not be so constructed as to divert the whole river but

merely to take flood waters and V give them a quick and safe getaway to the sea. In fact the flood water will not flow down this cut until the guage at Fitzherbert Bxidge, Palmerston North, is registering a ten or eleven foot flood. It will not be a permanent waterway as many people imagine, but banks will be constructed from the bend in the river at Dr. Walls’ corner to the river just north of Government Drain and from there down to the high ground at the southern boundary to the town, this latter precaution being necessary owing to the fact that when the flood water is diverted down the cut much more water will flow past Foxton to the sea. The cut will be 9i miles long and will cut out 29 £ miles of tortuous river in flood time. A tributary will be cut from the river just below Connolly’s camp to join up with the central cut, or pilot channel, in order to keep the lower portion of this channel sweet and to take away flood silt. Where the '“cut,” if such it can be called, meets the Manawatu River at Dr. Walls’, the river baulks will not he taken down below their natural level so that there will never be any fear of scouring at this point during a flood. The existing flood banks in this locality will, of course, be removed. ROAD ACCESS.

Mr. Hay referred to the road, access across the main cut on both the Wlhirokino and Shannon highways. At Moutoa, he said, on the foxton-Shannon road there would be no bridge but ramps would toe constructed up and down the protective banks. This area he estimated would not be flooded more than about three times during the year and the duration of the blockage would not be more than a day or so. It would take a twelve foot flood at Fitzkedbert to,- block the road and there were not more than one or two or those a year. In any case unless an “old man" flood was encountered there would not be more than -a foot or so of waler over the road between the banks. The position would not be , any worse than it was now as regarded the blockage of the road and would certainly be far 1 better because instead of the water lying around, it would get away much more quickly owing to the cut shortening the distance to the sea by 20 miles. At Wlhirokino an 80ft. low level bridge would be constructed over the cut at the site of the proposed new alignment of the road. In Mr. Hay's opinion it would be a good idea ilf the controlling authorities were to toitumenise the roadway oven the spillway at Moutoa as there would then toe no fear of scouring. In any ease the maintenance cost of the road would not toe as much as it was at present. He did not anticipate that the road would be blocked any more than for six days during the year. FROM FONT ON TO THE SEA. Mr. Hay said that the river would be navigable between the Foxton wharf and the sea. Years ago, he said, before the comprehensive scheme was thought out, he had submitted three sites of proposed cuts between Foxton and the sea to the Barbour Board, who after con-

suiting their engineer (Mi*. Jickell) and Mr. Furkevt (Uablic Works Engineer) selected the site that it is now decided on. After describing varibus details in connection with the scheme Mr. Hay was submitted to a lengthy questioning by Councillors. Cr. Ross asked if there would be any siltation at either end of the river between the wharf and tho seaj where it joined up with the cut. Mr. Hay: Had the comprehensive scheme been carried out, yes and, in a lesser degree, it will also obtain in the modified scheme. There will be a tendency towards siltation. ICr. Ross: Foxton’s . primary industry relies on getting liax down the river, how will this affect,us“? Mr. Hay explained that even under the comprehensive scheme provision would be made for getting the.flax down, the river to the mills. Under the modified scheme now Adopted, no interference would be occasioned to river shipping. The whole thing seemed to be that it was not realised that the cuts above Matakarapa and in the Moutoa were not cuts but spillways. They"would not have any effect on the river except in flood time. There would be half a million yards of sand to remove in the forty foot channel to be cut above ,Matakarapa and it would be many years before this cut enlarged, itself ,suffi--eiently to take the whole flood water. The flaxmills would not be affected as the cuts would not he deep enough to carry the main river. In the comprehensive scheme the river below Foxton would have been closed and made'into a lagoon but this would not obtain in the modified scheme. Had this obtained the sepiic tank outlet could have been carried out to the cut. With the banks right to Foxton and the spillways cut”, there would be considerably more water passing Foxton during a flood than at present. LAND ABLE TO SUPPORT SCHEME.

The Mayor: Do you think the land can support the expense of the proposal? Mr. Hay: Yes. Approximately 00,000 acres will be affected. The capital cost will work out at about 3/9 'an acre and the maintenance cost at 1/3. This latter figure allows for the spending of £3OOO per annum. The Town Clerk asked if the Moutoa spillway would not become overgrown with goatsrue as it would be a sort of “no man’s land.” Mr. Hay: Asuming that it does, is that not better than having 10,000 acres of swamp land. There was no fear of the land becoming overgrown with goatsrue, said Mr. Hay. The River Board w ! as comprised of level-headed men who were going to try and get some value out of the area. In any ease trees would be planted along the banks in the spillway. One hundred feet from the banks on either side, a belt of willows would be planted inside the spillway, and every ten chains or so a belt will be planted back towards the bank to meet a specially constructed spur bank. No willows would be planted on the bank itself as that would tend to weaken it but the whole banking would be 1 protected by a grid of willows. Will the Moutoa people bo blocked from getting into Foxton during a flood? was another question put to Mr. Hay.

His reply was that they would in big floods but no more so than they were now, in fact not so much. There would always he access to Shannon for them over the new Shannon bridge. In conclusion, Mr. Hay said that i! would lie impossible to confine the Manawatu river to its natural banks. The cuts or spillways would certainlv take up some good land but as far as possible he had endeavoured to make them pass through the poorest land. The scheme would toe of TREMENDOUS BENEFIT TO FOXTON. as Foxton would have to be the centre for the greater part of the y, ork which would he carried out between here and Moutoa. If material could be procured through the port of Foxton it would be done and the Harbour Board would benefit as a result. Some people imight look on it as a flash in the pan but the 'work would take at least five years to complete and the bulk of the money had to be spent around Foxton. The scheme would be carried through without hurting anyone as property acquired would he paid for and the owner compensated in every respect. The advantage to Foxton was absolute and would be still greater to Palmerston North. The •Manawatu-Oroua River Board did not want the financial support of any local body sited, it wanted the moral support of local bodies adjacent to and in the area affected by the River Board’s scheme to obtain a £1 for £1 subsidy from the Government. If the Board could obtain that from the Govern|ment then it would go to the ratepayers and explain the scheme and tell the people exactly what was proposed to be done and what the scheme would cost them. Until the subsidy was obtained it was not worth while going to the ratepayers. The Foxton Borough Council, said Mr. Hay in conclusion, was the only body which had asked him for an explanation of the scheme, which he was only too pleased to give to anybody interested, Tn thanking Mr. Hay for his interesting explanation, the Mayor said that, he felt, sure that the Council would give, favourable consideration to the scheme! and that a motion would toe passed at its next meeting's I feel sure that at our next meeting, said Mi’. Perreau, a motion will be passed in favour of the schejme.

Cr. Ross endorsed the Mayor’s remauks while Cr. Rand remarked that the engineer’s explanation of tin- scheme was very different from what the Council had been working on in the past.