British Columbia-Vancouver Island 138-kV submarine power cable

The paper describes the background and salient features of the 138 kV a.c. submarine cable interconnection linking the lower mainland of British Columbia with Vancouver Island. After a description of the electrical systems of the British Columbia Electric Co., Ltd., serving these areas, the requirements for additional power are formulated and the considerations leading to the adoption of a submarine cable interconnection are discussed. A following Section explains the determination of the cable route by hydrographic surveys, and the influence of physical site conditions on design and installation. The cable interconnection circuits and associated control, communication and protection systems are briefly described. The considerations resulting in the adoption of the pre-impregnated gas-filled type of cable manufactured in continuous lengths up to 15.6 miles, are then discussed, together with the development, design and performance characteristics of the cable and accessories; and the development, design, and installation of the special plant necessary for the manufacture and handling of the cable in continuous lengths are reviewed. The transport and installation of the cables and accessories are described in the following Section, and the methods and reason for landing the shore ends by a special scow are discussed. The paper concludes with a brief note on the field testing, commissioning and operating record of the cables.