TABLE 3 

 At West Street 



Year 



Distance of fathom lines in feet 



Two Three Four 



1938 450 650 1,500 



1949 700 950 2,475 



Gain + 250 + 300 + 975 



Similar gains, though of a lesser degree, were experienced opposite 

 the Beach Baths and the Old Fort Road. 



THE CAVE ROCK BIGHT SCHEME 



Due to the inability of the Railways Administration to maintain an 

 adequate rate of supply from the dredgers to feed the beaches with sand - 

 it had fallen from 70,000 cubic yards per month in 1938 to 27,000 cubic 

 yards per month in 1949 - the Council was forced to consider alternative 

 schemes, and adopted the second of the methods recommended by the con- 

 sulting engineers. This was the Cave Rock Bight Scheme, whereby a jetty 

 was constructed in the direction of the Cave Rock sand trap, and a pump 

 picked up the sand from the end of the jetty and pumped it to the Camper- 

 down Road area through a fixed line passing under the harbour entrance. 

 This plant, however, had its limitations - the movement of the dredging 

 arm was limited, and it relied upon the natural movement of the sand to 

 replenish the suction zone. The pump, therefore, although its capacity 

 was of the order of 200 cubic yards per hour, was only able to draw sand 

 within narrow limits, and during its four years of operation never exceeded 

 an average of 24,000 cubic yards per month. It will be appreciated that 

 this was an inadequate amount to make up the ravages of the erosive forces 

 in action on the beaches. 



SFFBCT OF SECOND SCH£ME 



The results of the Cave Rock Bight Scheme are best illustrated by 

 an examination of the various fathom lines during this period. There were 

 two stages of operation in this scheme, the first from the inception of 

 the scheme early in 1950 to April 1953, during which time the sand supply 

 was boosted to discharge at Bell Street and beyond, and the second stage, 

 when the boosting was discontinued, and the sand was discharged at the 

 base of the North Breakwater - this stage was one of nine months only, 

 but the results were significant, even for such a brief period. 



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