THE DIVERTED RIVER.

Waikato Times, Volume 103, Issue 17385, 23 April 1928, Page 8

THE DIVERTED RIVER.

CAUSES BIG EROSION. NO CAUSE FOR ALARM. After the first fury of its release over the spillway weir, the diverted Waikato formed a spectacular fall some distance below, where it leaped down to the flat along which the Waikato flowed. At this spot the lip of the fall was some 70 l'eet above the sand-flats, and in its approach the water boiled and spumed in wonderful fashion before finally leaping to the flat below. Recently it became very* apparent that consistent erosion was going on, and therefore it was no surprise when a great mass of rock at the top of the falls suddenly broke up and washed away. Though this has had the effect of detracting from the falls as a spectacular sight, no damage has been done or, interference with the work in hand caused, nor is it likely that any further big erosion will take place at 'this spot. A peculiarity of much of fcho local rock is that it crumbles and cracks .when exposed to the weather, and therefore it is quite to be expected that after thousands of years of such exposure much of the rock, w r hen again water-washed by such a raging torrent as the Waikato becomes at this spot, would fail to withstand the continual onslaught made on it.

Nevertheless, with great care and foresight, the Public Works Department immediately set about boring along the banks where the greatest erosion is likely to take place, with a view to finding out exactly the composition of the ground beneath the surface.

These bores have now been driven 50 and 60 feet, and the core brought to the surface is of a hard and close texture. A piece examined, which was brought up from a depth of 50 feet, closely resembles a fine concrete mixture which has set hard, and is not unlike a scythe stone at first glance. With such a foundation it would appear that there is little likelihood of it being necessary to divert the river to the tunnel again, so that the channel at the falls may be concrctcd. Though further minor falls of rock and debris may occur as a result of the continued erosion on the softened surface, there does not appear to be any likelihood of a fall which may cause trouble. No chances arc being taken, however, and the spot is being carefully watched.