IN DANGER

Manawatu Standard, Volume LVIII, Issue 177, 27 June 1938, Page 9

IN DANGER

CHRISTCHURCH POWER SUPPLY. GRAVITY OF LEAK IN TUNNEL. Per Press Association. CHRISTCHURCH, June 27. Through the development of a leak in the adit tunnel leading off the main tunnel between Lake Coleridge ’and the surge chamber at the power house a new me'nace threatens the power supply of the city. At present the water coming through the leak is a clear indition that there has been no disturbance of the shingle, but instructions have been issued by the Minister of Public Works (Hon. R. Semple) for the water to be cut off at the first sign of discolouration :in the leak. The tunnel in wl>jch ? tbe leak lias developed was built 'for constructional purposes and it was through this that the spoil from the main tunnel was removed.

«Xt is as well that the public should know the truth,’’ said Mr Semple to-day. “While the possibility of a breakdown cannot be ignored, there has been no indication yet that tho. country through which the tunnel has been pierced has shifted. So long as the water coming through the leak remains clear there will be no immediate danger, but if the water should come away in a rush through the shifting of shingle we will be faced with, a, calamity. There is no saying what amount of damage could be" done. In the meantime the leak must be regarded as a safety barometer. It must be watched day and night. While it remains clear it will be safe to carry on, but the moment it becomes discoloured the sensible thing to do will be to cut off the water.” The Minister added that serious

errors had been made in the construction of the tunnels. Cracks had developed in the main tunnel soon after the power house had been put into operation. This could have been prevented if the tunnel had been lined with reinforced concrete. The cracks had been grouted with cement, but though this method had overcomo the trouble temporarily, it could not give any lasting security. “With the expenditure of so much public money and so much depending on the successful and continuous operation of the power house, I am amazed that steps were not taken to obtain the maximum security,” added Mr Semple. “This is an engineering blunder of the greatest magnitude.”