SAND NUISANCE

Dominion, Volume 25, Issue 308, 23 September 1932, Page 3

SAND NUISANCE

Trouble at Lyall Bay i REMEDY REQUESTED Inadequacy of New Wall To impress upon the 'Wellington City Council the inauequacy of the new wall recently erec.cd along the beach side of Lyall Bay Parade to cope with the sand nuisance, a special meeting of the Lyall Bay Progressive Association was held last evening. The meeting, which was presided over by Mr. J. 11. Burgovne-Thomas, was attended by Councillors W. Appleton and R. Semple, who expressed their approval of a scheme to allay the nuisance, read by Mr. A. Howitt, who has made a close study of beach conditions. On the motion of Mr. Howitt, the meeting unanimously passed a resolution requesting the City Council to arrange for regular removal of sand which had drifted up the slope of the Parade wall aud so prevent it being blown over the roadway. The motion also urged upon the council the immediate reduction of the number of openings to the beach. The association advocated placing three of the openings as close as possible to the eastern side of the three buildings which were at present attached to the Parade. The chairman said that he was always very anxious to assist the council, but any advice in connection with the wall had not been taken. The association now claimed it was not the success that it was anticipated It would be. Geysers of Saud. In his report Mr. Howitt said that on every strong southerly wind each of the eight steps openings was a continuous spouting geyser of sand, throwing it to a height never attained before. This was causing greater detriment to the properties of the residents than before, and the continuance of the costly removal of the sand from the roadways and the tram-rail grooves despite the heavy cost of the wall erected to eliminate these three nuisances. “To those with a knowledge of the conditions governing the sand drift, prevailing winds, and the design of the wall on the beach side, the results accruing were hardly unexpected,” Mr. Howitt continued. "The structure as completed is composed of a sloped wall, rising from the beach level, and surmounted by a new portion which continues from the top of the slope in a curve which turns outward to form a lip. The action of the wind is to drift the sar.d up the easy slope of the wall, where it remains until the wind is strong enough to blow it up the curve, which acts as au ideal whirler, gyrating the sand in ever-widening circles until it is far enough out to be blown over the top as spray is blown from an advancing wave by a head wind. "As this sand conies over the wall near eye level instead of as previously at foot-level the effect on the pedestrians may be imagined. The result of the sand lying ou the sloped wall as detailed is to reduce the effective protective value of the wall from about 7ft. to about 2ft. 6iu. or so, being the height of the (protective?) wall. The report states that the remedy lies in a vertical wall eight or nine feet in height with a right-angle lip toward the beach, and in open wooden steps instead of the solid concrete ones, the report winding up with the opinion that “it would be quite safe to issue a challenge to any engineer to design a ‘protective wall’ which could throw more sand over it than the existing oue.” Councillors’ Views. Councillor Appleton said from what he had seen, it was apparent that much of the trouble was due to the sand banking up. This had the effect of making the eight-foot wall equal only to one three feet high. This sand should be removed by a horse-scoop. This would have to be done by either the reserves, beach or tramways committee. When the wall was first erected the nuisance was abated, until the sand banked up again. Councillor Semple said that he wax satisfied that the theory put forward by Mr. Howitt was perfectly sound. It was never intended that the sand should bank up as it was now doing. As it banked up, the whirling sand was lifted higher and higher. “I am sorry that the wall has proved unsatisfactory, but I think it can be made 106 per cent, more efficient,” Councillor Semple said. “Something will have to be done, or the money we have spent is positively wasted.” Mr. C. F. Lethaby, representing Island Bay ratepayers, said that his district was faced with a similar difficulty, and they were watching the Lyall Bay efforts with interest. The two councillors were accorded a hearty vote ‘of thanks for their attendance, and before leaving, promised to bring the question of the sand nuisance, which they saw was a real one, before the City Council works committee.

DIAGRAM OF SAND DRIFT A diagram of the criticised sand deflecting wall at Lyall Bay appears on the illustrations page in this issue. The numerals on the diagram have the following significance:— 1— Section of original sloped wall. 2— Section of new “whirler'’ wall. 3— Sand drift from light winds-laying on sloped walls and reducing the effective protection. 4— Arrows show action of sand-infested strong winds on drift sand and whirler wall, throwing sand over to roadway.