AUCKLAND HARBOUR BRIDGE.

Auckland Star, Volume LXVII, Issue 237, 6 October 1936, Page 14

AUCKLAND HARBOUR BRIDGE.

Your correspondent E.C.S. estimates that the above would entail a capital expenditure of £5.000,000 and an annual recurring expenditure of £200,000. These figures are correct only for the most expensive type of all —a high-level bridge to allow of the passage of ocean liners. This type is ruled oiit of consideration, because the maximum anticipated gros: revenue —as I estimate it—rthat could be earned by the Auckland harbour .biidgt is about *£80,000 per annum only. This sum capitalised at 10 per cent for all charges gives £800,000 as the maximum permissible capital cost of a bridge for | Auckland- harbour. No known type of [ bridge, supported on piers, could be built for sucli a small sum, but a' very fine low-level floating bridge —with a quickacting opening span for ocean liners--could be built for Auckland harbour for even less than the above sum, because the heavy' expense of all the piers is eliminated. If necessary this floating bridge could be Built entirely in ferroconcrete, including the pontoons. I would mention "that the floating bridge over the Hooghly River, connecting Calcutta and Howrah —carrying a very heavy traffic and serving a population of 1,500,000 — cost only £2-20,000. This floating bridge has withstood cyclones and strong tidal bores for 62 years —a great tribute to its designer, the late Sir Bradford Leslie. THOMAS A. F. STONE, B.E.