NORTHERN RAILWAYS

Sun (Auckland), Volume I, Issue 161, 28 September 1927, Page 6

NORTHERN RAILWAYS

SPEEDING U!P CONSTRUCTION That the Public Works Department is doing its best to speed up the work of connecting the Dargaville-Kaihu section the North Auckland Main Trunk line is shown by a perusal of the figures in connection with the construction of the railway bridge across the Northern Wairoa River at Pukehuia. The actual cost of the bridge was £2 5,537 19s sd. which is about £3,900 below the estimate. The bridge was officially opened for traffic on September 24, nine months ahead of the estimated date. June, 1928. DIFFICULTIES OVERCOME The section from Waiotira to Kirikopuni, the present terminus, which is slightly over 14 miles in length, has 26 railway and road bridges, including the main bridge across the Northern Wairoa River, and with the exception of two miles has been formed through very bad country. Two tunnels, ore of 28 chains and one of 32 chains, have also been constructed. In addition, the department has had to wrestle with the serious problem of unstable flats. To give a concrete instance, in one case a 16ft. bank had to be formed with sufficient material to make an 80ft. bank on solid ground stability was reached. The traffic on this section has shown a marked increase since the first train, was run from Waiotira in November. 1925. Comparing the returns of th€! winter months of the present year with those cf the same period of last 3' ear. the traffic shows the following increases Passenger, 80 per cent.; outwaxd goods. 144 per cent.; inward goods, 207 per cent. Ir. is anticipated that the summer traffic will show r. much greater Increase. THE RIVER BRIDGE

The bridge across the river consists of two 105 ft. steel trusses, two 45ft. and fifteen 30ft. girder spans, a total length of about 750 ft. The main 105 ft. spans are carried on reinforced concrete cylinder piers, two cylinders to each pier. These cylinders, between eight and nine feet in diameter, are sunk 20 to 30 feet below the bed of the river into solid rock. The average total height of the piers Is about 70ft. The c learance of the main spans above high water mark is about 24 feet. Each of tfa 2 main spans weigrhs 75 tons and the t*tal weight of steel in the bridge is about 275 tons. The whole work reflects very greai: credit on the engineer and staff, and the early completion of this section augurs well for a successf j] termination of the extension to Dargaville at no very distant date.