BATTLE OF ROUTES

Evening Post, Volume CVI, Issue 27, 1 August 1923, Page 9

BATTLE OF ROUTES

EARLY ENGINEERING

CANNIBAL GORGE V. OTIRA

Wherever there is a railway there is a route fight. Between 1874 and 1883 numerous surveys of proposed routes ■were made, and three routes stand out notably. These are the route now adopted, connecting the Bealey and the Otira Valleys under Arthur's Pass; the Cannibal Gorge route, connecting the Amuri Plains with the Inangahua valley at Reefton, via the Lewis Saddle;' and the Hurunui &?rge route, from Waikare to Jackson's. Until the contract, for the present route was actually let in 1907, people in Reefton and some in Westport agitated strongly for the Lewis Saddle route, while the Grey Valley people stood for Bealey-Otira. Harbour rivalry between Westport and Greymguth entered, into this controversy. FELL SYSTEM DROPPED. The Bealey-Otira route . received its first strong authoritative backing in 1883, when a Royal. Commission reported in its favour. The later 'eighties and eralier 'nineties saw the initiation and failure of the Midland Railway Company. In 1900 a committee of engineers was set up to consider the best means of crossing the actual dividing range— whether to adhere to one of the original proposals (a 1 in 15 grade, with Fell centre-rail system, over the range) or to

have a long summit tunnel. The committee decided in favour of a summittunnel about six miles long, with a grade of approximately 1 in 37. I In 1902 Mr. V. G. Bogue, an eminent American engineer, was called in by the New Zealand Government, and, after I considerable investigation, he recommended a line with a shorter summittunnel on a grade of 1 in 32. As he considered that a lino with a summiti tunnel on such a steep grade was quite i suitable, further surveys were made; and a line with a summit-tunnel on a grade of 1 in 33, and in its present j position, -was finally located. This proposal was submitted to Mr. Bogue, who confirmed the recommendations of the local engineers, and it was finally decided to adopt this route. Mr. Bogue was assisted in his report by Mr. E. W. Holmes, who, later on, as Superintending Engineer and principal assistant t<o the then Engineer-in-Chief (Mr. P. S. Hay), took the chief part in preparing the specifications for the tunnel contract. In April, 1907, Mr. Holmes succeeded Mr. Hay as En-gineer-in-Chief, and on 12th August of that year the contract for driving the Otira tunnel was let- to Messrs. J. H. M'Lean and Sons for £599,794. The time for completion was fixed at five years. The contractors began to drive the bottom heading, at the Otira end, in April, 1908—on sth May of that year the Prime Minister, Sir Joseph Ward, fired the first shot—but the work proved to be too great, in the circumstances,' for private enterprise, and it was taken ' over by the Government, before it was half completed, in December, 1912. The contractors had driven 2 l-3rd miles, of which 1J miles was lined and completed Over five .years and a half elapsed before the operation*, directed now Jby thej

Public Works Department, resulted in the bottom headings meeting in July 1918. By the middle of 1920 the tunnel was ready for the final stage, electrification, now completed by the English Electric Company. Here are some of the main points of the Otira tunnel: Length: 5 miles 545 yards. Height: 15 leet 6 inches. Width: At rail, v feet; at widest point, 15 feet Grade: Uniformly I | n 33, dipping from east to west. Altitude: Eastern end, 2435 feetwestern end, 1585 feet; fall, 850 feet. The altitude of Arthur's Pass is about 3000 feet; that of Mount Cook's summit, 12,349 feet. The tunnel carries a single-track railway of 3ft 6in gauge, which is the standard gauge of the New Zealand Government railways. In cross-section the clear height above the rail-level is 15ft 6in with a maximum width of 15ft. ' POWERS EMPLOYED. ' The primary powers first utilised at Otira'and Bealey were used for driving the tunnel. Hydro-electric power was generated from Holt s Creek at the Otira, end, and from the Punoh-Bowl at the Bealey end The Punch-Bowl was fairly equal to the contract, but the effect of dry summers and midwinder freezing on Holt's Creek .is so pronounced that a n assistant steam

station was set up at the Otira end, to keep the tunnel works going. It maybe added that most of the excavation of the tunnel was done from the Otira end, because that end is the lower one, and the 1 in 33 dip of the tunnel taade outward haulage easier, and allowed the water to flow out, whereas at the Bealey end the water had to be expelled by being pumped up the grade. Later on came the question, Triiht tractive power to use for the railway service, and how to generate it. Length of the tunnel, and its grade, necessitated electrical traction. But the power need-e-l was far in excess of the hydro-electric possibilities of Holt's Creek and the Punch-Bowl. Therefore the plant generating electrical power in the new I power-house at Otira is driven by coal ■and steam. To say that is not to say that hydroelectrical; power will never supply the tractive effort. According to an official publication, " in the future, when power becomes available, it is intended to link i up the line with the hydro-electric sys-' tern, and to use the steam plant as a stand-by." NEW OTIRA TOWNSHIP. The station buildings at Otira, of the type familiar to New Zealanders, are situated on an island platform, and are large and well-appointed. An electrical-ly-lit subway gives access to the plat-

form, thus dispensing with an overhead bridge. . A township of 50 houses has sprung up to accommodate the workers to be permanently employed in connection with the operating of the tunnel. The houses are of the bungalow type, fitted with electric light and all conveniences, and bear no resemblance to the usual railway houße of monotonous design and colour. Each is located on a quarteracre section, on either side of a wide central roadway.. A neat building is the hostel erected for waitresses employed at the refreshment rooms. At Arthur's Pass station, on the Canterbury side, more workers' houses have been built, anid are connected -with drainage and water supply, similar to those at Otira. Passengers making the overland journsy will now secure lunch at Otira instead of at Arthur's Pass, as formerly. The new rooms at Otira are among the finest in the Dominion, being designed with a view to comfort and efficiency. PROGRESS TOLD IN DATES. The driving of the Otira tunnel was idn Un ty Private contractors in May, 1908, and was taken over' by the Government in December, 1912. On 7th May, 1918, the men at the Jiealey end of the tunnel heard the firing of the explosives used at the Otira end. On 20th' July, 1918, the bottom headings of the tunnel met—3 miles 68 chains 10 links having been driven on the upgrade from the Otira end, and 1 mile 37 chains 44 links on the down-grade from the Bealey end. The electrification contract was let to &?Msr&(^ in Aiisust'