TABLE 1 



Year 



+ Accretion 

 - Depletion 



Comment 



1846 

 1903 



1913 



1935 



1949 



+ 720 feet 



- 174 feet 



- 130 feet 

 + 400 feet 



Earliest records 



After construction of break- 

 water 



After 10 years regular 

 dredging operations 



Further recession after over 

 30 years regular dredging 



Recovery following sand 

 pumping to South Beach 



Records of low water over the above periods follow a similar pattern. 

 It is not possible to give similar records for positions along the Central 

 Beach however, as the high water has been restrained by the protection 

 works along that stretch. 



WIND DRIPT 



In considering the area above L.W.O.S.T. , it would be incorrect to 

 ignore entirely the effect of wind drift. This factor is one of some 

 magnitude in Durban, and frequent use is made of graders and bulldozers 

 to recover the sand which has been piled up above H.W.O.S.T. , and even 

 further afield. It would seem that wind-blown sand could only be taken 

 from the dry stretches of the beach, but observations indicate that 

 apparently dry sand can be blown in considerable quantities from beach 

 areas still wet from a receding tide - in fact, winds as low as Beaufort 

 Scale 4 (about 15 miles per hour) have moved sand from this moist area. 

 The evaporative effects of the wind are thus important in increasing the 

 erodibility of the sand. 



PROFILE OP EQUILIBRIUM 



It is not difficult to investigate the movement of sand on the beach 

 itself, but it is more important to know what is happening at the lower 

 levels of the beach profile. Dr. King defined an offshore profile on a 

 well-established sandy beach as a gradually flattening curve seaward 



15 



