The East Bay Neck Ship Canal, Tasmania.

Abstract

THE folIowing is a brief description of a ship-canal across East Bay Neck-a peninsula on the east coast of Tasmania-the construction of which has been recently completed, providing a waterway between Frederick Henry Bay, near Hobart, and Blackman Bay, near Maria Island, and thus saving a long and often very stormy passage round by the open sea.The canal is 7 furlongs in length between the low-water marks on either side of the peninsula, and long approaches have been dredged to deep water at either end of the canal. The greatest depth of cutting is about 33 feet, the material excavated being clay, with layers of sand. Dams were constructed at the ends of the canal, and the excavation was performed in the dry, springand rain-water being removed by continuous pumping.The cutting is 18 feet in width at the bottom, the side-slopes being 2 to 1 ; and the approaches are 33 feet in width. A siding is provided to permit of vessels passing one another. The depth of water in the canal is 10 feet at, low-water, the tidal range being 5 feet.A swing-bridge of 30 feet span has been erected to take the main road over the canal. The roadway is carried on iron girders supported on a concrete pier, and sufficient space has been provided to permit of widening and deepening the canal, if required, in the future.From observations made previously it was calculated that a current would flow in the canal from north to south ; it is now found that a current of 2 to 3 miles an hour flows in winter from south to north, and in summer from north to south, with irregular intervals during gales.The canal is intended for the use of coasting-steamers and fishing-craft, and was constructed from plans and specifications prepared by the Author. Downloaded by [ UNIVERSITY OF MINNESOTA] on [12/09/16].