SURVEY FOR TUNNEL

Dominion, Volume 32, Issue 146, 16 March 1939, Page 10

SURVEY FOR TUNNEL

Rimutaka Hill Project OTHER JOBS TO FINISH FIRST Latest Methods To Be Used TRANSFER OF EQUIPMENT AND MEN Survey work is being done as a preliminary to the construction of the tunnel it is proposed to pierce through the Rimutaka range. The Minister of Public Works, Mr. Semple, in an interview last evening, said the actual construction work would not be commenced till some of the present tunnelling jobs had been completed and the necessary mechanical equipment and experienced tunnellers could be transferred to the Rimutaka project. A survey over the top of the Rimutaka Range, said Mr. Semple, was an essential preliminary to the construction of the tunnel. The survey pegs would provide the means by which alignment would be maintained and centres would be checked with a theodolite during tunnelling operations. “We are not going to buy any new tunnelling mechanism for the construction of the tunnel through the Rimutakas,” said Mr. Semple. “When some of the present tunnelling jobs on the South Island Main Trunk railway line and on the East Coast line are finished we will transfer the mechanical equipment from them. There is also the difficulty of obtaining trained tunnellers. It is not intended to make a start with the work till some of these other jobs are completed, and. we can transfer the men to the Rimutaka tunnel.”

Mr. Semple said that in the meantime he was looking into the latest tunnelling methods practised abroad, particularly in the United States of America, so that the most modern methods could toe used when a start was made with tunnelling. He was not altogether satisfied that the methods at present in use in New Zealand represented the latest in underground work;

The decision of the Government to construct the tunnel was announced last June by the Prime Minister, Mr. Savage. The cost has been estimated at £1,000,000. The route of the tunnel will be from Mangaroa to Cross Creek, and it will shorten the distance by rail between Wellington and the Wairarapa by eight miles, and in addition to eliminating the existing sharp curves, it will replace gradients that range from one in 15 to one in 28, with an easy gradient of one in GO. The tunnel, when driven through, will be about the same length as the Otira tunnel, which is the longest railway tunnel in the British Empire.