Canadian Coast Guard
<% else %>A History of the Canadian Coast Guard and Marine Services
by Thomas E. Appleton
The Offshore Tower
As we have seen, lightships were sometimes swept away by gales or ice and, subject always to the unpleasant or violent motion of a small ship at anchor to exposed tidal waters, life could be extremely trying for crews who often went for long periods without relief. With the advent of the second world war the outlying lightships, which in any case might have tempted fate as targets for enemy action, were removed to fill an urgent demand for gate vessels to operate antisubmarine booms at naval ports. After the war was over the Department made a critical review of the principles underlying their use and the Gros Cap lightship, at the eastern end of Lake Superior, was replaced by a concrete structure in 1953. Erected on the site, this is a conventional pier with an "ice nose" facing upstream, surmounted by small buildings reminiscent of the pilot house of a big laker; indeed, viewed in half light from a certain angle, the Gros Cap is strangely like a ship, not much bigger than the converted naval trawler which had previously carried the light, but with superstructure like the great inland carriers which pass in constant procession. The crew required to operate such a light station is very much less than for a lightship.
Offshore towers, whether as aids to navigation or for other purposes such as defence or oil drilling, had been built in ever increasing numbers throughout the world during and since the war, and their design had undergone much revision when, in 1956, a radically different type of aid was put into service in an exposed position to replace the White Island lightship in the Lower St. Lawrence. While the Gros Cap is relatively small, a similar kind of concrete island scaled up to meet the conditions of the Gulf of
The Gros Cap lighthouse at the eastern end of Lake Superior. A concrete structure built in 1953.
St. Lawrence would have been heavy and costly and would have been almost impossible to erect in place. Slender structures on the other hand, such as the multi-legged steel fabrications of offshore oil rigs, cannot stand the enormous forces of heavy ice, and the problem called for a solution to meet this condition.
The answer to this difficulty, typified by the White Island structure, and of a kind developed and used only in this country, takes the form of a cone resting on the bed of the sea with another inverted cone on top. These two cones form a waisted structure with a flat circular deck on which in erected the beacon pillar as in conventional light stations.
This double cone design, looking for all the world like a reel of thread, has the stability of a pier while presenting the minimum area to surface ice. The lower cone, with its receding slope to oncoming drift, helps to break up the frozen pack while the upper cone, stretching its perimeter over the surrounding water, deflects the action of the waves.
The Sand heads lighthouse, of steel piling, which replaces the former lightship off the Fraser River.
The White Island station was very successful. The main body of the structure was built in a shipyard before being towed out and sunk in position, and the cost was roughly comparable to that of a lightship. The latest version of the type, the Prince Shoal light station, established in 1963, has a light 100 feet above low water. This station has a motor launch hoisted in and out by powered crane and is arranged to receive a helicopter on the circular deck. The superstructure contains an engine room, radio beacon room, four bedrooms, a living room and a kitchen-dining room. This is indeed in contrast to the old Manicouagan, not very far away, where Captain Connell was isolated for six months. As he brooded over his carefully considered plans under a swinging oil lamp in the cramped quarters of the old sailing ship, wondering how long he dared remain on station, his decision to leave in a gallant attempt to save the lives of fellow seamen was in the great tradition of the lighthouse service; true to this tradition, the one quality which time and modern techniques will never change is the spirit of service implicit in all who man our aids to navigation.
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