LAKE FORSYTH OUTLET

Press, Volume LXXIV, Issue 22305, 20 January 1938, Page 4

LAKE FORSYTH OUTLET

EFFECT OF ADVANCING SHINGLE

COMMENCEMENT OF WORK

DELAYED

The movement of shingle near the proposed site for the permanent outlet for Lake Forsyth has made further investigations necessary before the construction of the outlet is begun, according to the District Engineer in Christchurch for the Public Works Department (Mr F. Langbein). Mr Langbeln said yesterday that if the shingle continued to advance at the present rate the suggested outlet would have a very short life before it was smothered.

The proposal was to excavate an open cutting along the shingle bank to the rockpoint lying to the east of the lake outlet, through which a tunnel would be driven. The proposed outlet of the’tunnel was at a point which had not been affected by beach shingle. A study had been made of the movement of beach shingle in the locality by questioning persons who had known the locality for many years, and they considered that the proposed location of the tunnel would remain free from any influence of the beach shingle for many years, if not perpetually. Mr Langbein added that in a report made in 1875 it had been stated that the shingle bank extended a certain distance along the cliffs. From this statement, it appeared that there had been a certain accumulation of shingle, but apparently it was taking place slowly. "But a peculiar thing has happened recently,” Mr Langbein said. “Following on the heavy seas which have been experienced, the shingle bank has built out seaward very rapidly, and it appears that further consideration will have to be given to the question before the construction of a permanent outlet is undertaken. The shingle has extended seaward for about one chain, and the shingle bank now extends four or five chains further along the shore at the rocky point than it did previously. It would be possible to lengthen the tunnel and carry the outlet farther round the point, but even if this was done and the shingle continued to advance a permanent outlet would have a very short life before it was smothered by the shingle.”