NO DANGER

Ashburton Guardian, Volume 61, Issue 146, 2 April 1941, Page 6

NO DANGER

FLOODS IN BOROUGH.

ASSURANCE BY ENGINEER.

REGENT OVERFLOW INSPECTED. will r£c6mm£nd PROTECTION bank west of the bridge. An assurance that the Borough of Ashburton generally was in no danger of being, flooded from the Ashburton River was given to the Borough Council to-day by the District Engineer to the Public Works Department (Mr T. G. Beck), who planned the river control scheme. Mr Beck accompanied members of the Council on an inspection of the place where the river overflowed into the old course the river used 40 and 50 years ago.

The engineer was accompanied by the Mayor (Dr. J. Connor),- several members of the Borough Council, the Town Clerk (Mr R. C. Major), the Borough Engineer (Mr .T. R. Richardson), the Borough Solicitor (Mr L. A. Charles) and Mr J. 0. Riddell (Engineer in charge of the control work.

Mr Beck pointed out that the scheme provided for the placing of a single sheet of water over the whole of the flat country between the terraces in time of flood and added that the flood two weeks ago had been very little below the maximum that had been allowed for in the planning. At the point behind the woollen mills where the willows were removed and where the river swung toward the north bank and carried away several acres of flat land, Mr Beck showed the Council by means of plans, what had been plotted and said that what had been calculated was what had happened in the last flood.

Bed Rises Three Inches In 80 Years. On the question of river water flowing along the north terrace and the contamination of the wells for the town supply of water, thought to have been dufe to the flooding in this direction, Mr Beck said this was a local problem, one that the Public TV orks Department might be able to give some assistance in solving. The willows that had been removed, he said, had to be taken out to give the clearance for the water in the river. The engineers had sought all the local information about the river they could get and he denied that anyone had approached anyone in authority regarding the possible danger of flooding over into the old course of the river. In the course of a discussion on the whole position, Mr Beck, answering many questions, said that figures available showed that the bed of fivbr at th'e traffic bridge hhd risen only three inches in the last 60 years. In every flood there were factors which coiild not be computed beforehand. For the protection of local buildings on the fiats south of the terrace on the north side of the river he thought something could be done in the way of running a small bank westward from the traffic bridge, which would keep the water out of the Power Board land and away from the Public Works Department’s sub-station.

Contamination of the Welfs. Below the bridge, on the town side, ho added, the original plans for the river control scheme provided for a stopbahk to be erected for a certain distance. Flood water might back up behind that to a minor extent from the lower end of the bank.

Speaking on the question of the contamination of the wells, Mr Beck said that there was drainage from the woollen mills which might possibly have had something to do with the contamination.

Mr E. Buchanan pointed out. that it was the first time in 30 years that the wells had been contaminated and it followed the flooding along the terrace where there had not been any flooding before the willows were removed.

Mr Beck: You have got a menace there, certainly, but whether it is a big one or not has to be found out by a study of the position. He added that the County Engineer (Mr H. A. Yezey) was of the opinion that the last flood was tiie biggest there had been for many years. If several miles of willows in the waterway had not fieen removed the trouble would have been much greater than it turned out to be. Waterway Under Bridgie Deepened. In reply to Mr Charles, Mr Beck said the flood had deepened the waterway under the traffic bridge. It was a very different thing higher up the river, where no clearing of willows had been carried out.

It was not always a good thing to have a long straight cut in the waterway, Mr Reck pointed out. That would tend to deep scouring, so the plans were to have the water swung from point to point with curves. Straight cuts would, only lead to rapid erosion. The only harm the flood would do in running into the old course, the engineer said, would be its actual presence there. There was too much growth there to permit the water to run swiftly. He was having levels taken at the present time- with a view to doing something to prevent local flooding near the bridge. Mr Riddell expressed the opinion that as there was water on farm lands on both sides of the river at some points, where it. had not been for many years, the flood must have been; the biggest for about 40 years.

Viewing the Power Board land, Mr Bock said that a four-feet bank upstream from the bridge would give protection and achieve all that could be desired.

Mr H. G. Kemp (Engineer-Secretary to the Power Board) said the board was interested iii keeping the water off

that land, and Mr Beck replied: “We intended to flood this area.”

Mr Kemp: But why not have left the river where it was ? Mr Beck said it had been intended all along to bring the flood water over that land. It would not be economically sound to put in protective works for the leasehold land higher up the river.

Mr Kemp: L can't understand why you took those willows out (referring to those removed near the woollen mills). ' Mjr Beck: Tie had to have the waterway. No Failure in Control Scheme. Mr Kemp: Wouldn't it h ave been bettor to Mve taken out some on the other side of the river ? Mr Beck: You could debate it all ways. Mr Beck displayed the control work map, pointing out where the waterway had been planned. Mr Kemp' contended that the water was running from the goiifh branch toward the north bank at the junction and not in the line shown on the plan where the new ■Waterway was marked. Mr Beck differed in this After further discussion Mr Beck said: “The town is secure from floods as it could be, and I cannot accept the principle that there has been any failure in the control scheme.” He said he would recommend the placing of a bank to protect the power house and' the buildings in that vicinity.