Tops to be taken off railway tunnels

Press, 17 March 1982, Page 13

Tops to be taken off railway tunnels

PA - Wellington The Railways will have to take the top off five tunnels on the North Island Main Trunk line to permit electrification. The tunnel jobs, termed "daylighting" in railways jargon. are required because the tunnels are not big enough to take the new electric locomotives plus overhead wires. The jobs are part of earthworks costing more than $3O million planned by the department in its $lBB million scheme to electrify the Main Trunk between Palmerston North and Hamilton. The Assistant General Manager of Railways (engineering and development), Mr Robert Henare, said that earthworks had already begun and programming had been agreed to. “The concentration of works is between Marton and Palmerston North, which we want to commission as a test section by August or September, 1984,” he said. "We have started curve easements and other earthworks, but that is fairly level ground compared with what we have coming up. "We have to daylight five tunnels because at the moment we would have difficulty getting the wires through with enough clearance. We ■ have the choice of either widening the tunnel or taking the top off and making it a cutting, and in these cases it is easy to knock the top off. “It can be difficult because we have to keep running

traffic through the tunnel while work is in progress.” Mr Henare said that the department was now accepting “registrations of interest” from manufacturers interested in building the 22 electric locomotives needed for the Main Trunk. Those who list an interest will be given detailed tender documents when the formal tendering period opens in July. It will close in November. Mr Henare said that at one stage, the Railways feared that it would be possible to get enough locomotive power only by coupling two for the hill-climb sections. "We believe now after discussions with manufacturers that we can get the power we need in a single locomotive," he said. The department expects to go to tender for the overhead poles and power equipment before the end of the year. Its requirements in this area have been studied by Jarts, the technical arm of Japanese Railways, and have been discussed with the Electricity Division. Jarts’ British equivalent, Transmark, has been acting in a similar advisory capacity for signalling equipment. Electrification will be introduced by commissioning several separate sections of track, finishing with the Tau-maruni-Hamilton section in early 1988. The whole project will provide about 200 jobs for workers employed by contractors.