TUNNELS AND BRIDGES.

Hauraki Plains Gazette, Volume XXXVII, Issue 5030, 22 September 1926, Page 4

TUNNELS AND BRIDGES.

EAST COAST RAILWAY WORKS. GREAT UNDERTAKINGS. It can easily be understood (says the Napier Telegraph) that, considering the type of country through which the Napier-Wairoa section of the East Coast railway passes, tunnelling and bridge work form the mos.t important task of construction. Tunnels of great length have already been completed, and more have yet to be bored, while the next 12 months will see much activity in the matter of spanning the rivers that cross the route at .intervals. To take the bridges first, one, the Esk bridge, which crosses the river some few miles north of Eskdale, has already been completed, and a fine piece of work it is, with its symmetrical concrete columns and accurately placed s.teel girders. The bridge is 400*ft. in length and tofwers scores of feet above the water level. Taking the whole of the line Hom Napier to Wairoa, five very laj’ge viaducts or bridges will have to be put up before the line can be pushed through. All these bridges, will be conctructed with steel lattice piers. A start has already been made with the bridge which is to cross the Waikoau stream at a point jus,t noi th of Waikoau station, a.nd distant from Napier 28% miles. Thia bridge will be 500 ft long, with an elevation from the water level of 235 ft. The Matahora bridge, which is about to be started, is a similar structure to the Waikoau bridge. This ajso will have steel lattice girders, with a, span of 250’ft. Both the Waikbfeu and Mataora bridges will require each about 600 tons of steel works, and the contract to supply this has. already been let to Messrs Vickers, of England, ami the material should arrive in the Dominion ajiout the end of this year. Before either of these bridges can be built a wooden trestle bridge, in duplication of the bridge to eventually go up, will have to be constructed in each case, so the wdrk on the steel bridges can be proceeded with. The Matahora bridge cresses the stream at a point 34% miles, fiom Napier. The Waikari viaduct, when it, js started, will be'39 miles from Napiei. This will be a 600 ft long bridge with 100 ft spans. The towers carrying the spans will have a width of 50ft, and the whole bridge will'be 250 ft abowe water level. The Mahaka bridge will be the biggest of the lot, and will be constructed in six 100 ft spans- with a total length of 950 ft. The elevation in this case will be 320 ft. Maungaturangi bridge, to be set up at a point 52% miles from Napier, will consist of five 100 ft spans and five steel towers. The length oft the bridge will be 750 ft with an elevation of 220 ft. The tunnels on the line commence soon after leaving Waipu.nga, and there are three, between that place and Wajko'au. Number . one is the longest, this having a length of 700 ft, while numbers two and three are 330 ft and 390 ft long rspectively. All these three are completed. Beyond Waikoua, in the Mohaka section, there are three more tunnels to be constructed and preliminary work in connection with these is already under waq .Th fir,st will be just over hal'f a mile in length, while the second, 47 miles from Na,pier, and the third, 48 miles frcfai Napier, will ha,ve respective lengths cf 1080 ft and 1131 ft. Preliminary work has also been commenced on two other tunnels in the Waihua section. One, 2240 ft long, is 57 miles from Napier, and the other, 720 ft in length, is 63 miles away.