being effected through a 42" pipeline to a point on the South Beach op- 

 posite Camperdown Road; the first deliveries were made in January, 1938. 



Six months later the Corporation installed a special dredger pump 

 by which the sand was picked up at this point and deposited at selected 

 points opposite Bell Street and Rutherford Street. This scheme remained 

 in operation until July, 1949 - a period of eleven years. During this 

 period more than 5,000,000 cubic yards of sand were delivered to Vetch's 

 Bight from the Administration dredgers. 



FIRST RESULTS OF SAND PUMPING 



An examination of the sand accretion and erosion of the three beaches, 

 namely the South, Central and the North, during the period between 1938 

 to 1949, is of considerable interest in relation to the effect of the 

 littoral drift. Sand was delivered mainly on the South Beach on the 

 assumption that the northerly drift would take much of it up to the Central 

 and Northern beaches without further pumping. However, it was observed 

 that the bulk of the sand remained on the South Beach, and as the accretion 

 there agreed remarkably closely with the average monthly dredger outputs, 

 it appeared that the sand would not leave this beach in any great quantity. 

 It is therefore reasonable to assume that the anticipated littoral drift 

 northwards did not occur in the vicinity of the South Beach, which confirms 

 a theory advanced by earlier hydrographers to the effect that there is a 

 reverse current in the vicinity of the Vetch's Bight. Although this cur- 

 rent is not of any great strength, it is apparently adequate enough to 

 affect the normal flow to the north, so that over the years much of the 

 sand pumped to the South Beach remained in the vicinity. 



An examination of the various fathom lines over this period indicates 

 the marked progress made, particularly in the vicinity of the South Beach, 

 where the bulk of the sand was dumped. Booster stations gave additional 

 feed points at Bell Street (1938-49); Rutherford Street (1938-48); and 

 West Street (during 1938 only). Tables 2 and 3 indicate the distance off- 

 shore of the various fathom lines, measured from a fixed point. 





TABLE 

 At Bell St: 



2 

 ree 



it 









Year 



Distance i 



3f 



fa 



thorn lines 



in 



feet 



Two 







Three 





Four 



1938 

 1949 



750 

 1,050 







1,300 

 2,375 





2,450 

 3,750 



Gain 



+ 300 







+1,075 





+1,300 



18 



