severely eroded, with consequent threat of movement of the structure itself, 

 and, incidentally, the formation of dangerous bathing conditions. 



FUTURE DEVELOPMENTS 



From the experiences of the past twenty-four years, during which the 

 City Council has endeavoured to preserve its ocean beaches against erosion, 

 it is clear that artificial means of beach replenishment must be continued, 

 and that the minimum quantities to be provided by these means must be of 

 the order of 300,000 cubic yards per annum. In an effort to recover lost 

 ground, this quantity should be considerably augmented in the near future, 

 up to 600,000 cubic yards per annum. 



Together with this artificial supply, adequate and efficient groynes 

 must be built to hold the sand aud, once the whole position of equilibrium 

 has been restored, it should be possible to reduce the artificial feed to 

 a nominal quantity. 



The most important aspect which requires further research is the 

 question of the sand-retaining structures. The form, dimensions and placing 

 of the future groynes can only be determined after considerable research, 

 and the final conclusion may be quite a radical departure from the normally 

 accepted form - particularly in regard to direction. 



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