§ Mr. Hooleyasked the Secretary of State for Defence (1) what were the depths of the unchartered wrecks, the chartered depths in their vicinity, and the dates of the last relevant surveys on which the charts were based;
(2) how many unchartered wrecks and shoals hazardous to deep draught shipping have been discovered in 1977 in the waters surrounding the British Isles.
§ Mr. DuffySo far in 1977, some 600 sea-bed obstructions have been discovered in home waters; 13 of them have been definitely identified as wrecks potentially hazardous to deep draught shipping. Ninety previously uncharted shoals have also been found, of which 40 could endanger deep draught shipping.
In the time available it has proved possible to obtain the additional information requested for three of the 13 wrecks. All three are in the Dover Strait. One has a least depth of 22.1 metres in general depths of 29 metres; another has a least depth of 19 metres in general depths of 27 metres; and the third has a least depth of 16.9 metres in general depths of 26 metres. The previous survey of the area of these wrecks was carried out in 1962, before modern side scan sonars became available.