THE SYDNEY WATER SUPPLY. 



219 



STATEMENT "A." 













Discharge 





Storage 





Average 





from catch- 





capacity of 



Catchment 



annual 



Percentage 



ment areas 





reservoirs 



areas in 



rainfall 



of rainfall 



from aver- 





in millions 

 of gallons. 



square 

 miles. 



over catch- 

 ment areas 

 in inchss 



discharged 



age annual 



rainfall in 



millions of 



gallons. 



Wingecarribee No. 1 



Wingecarribee No. 2 



10,000 1 

 10,000 f 



55 



50 



44 



17,545 



Chain-of-Ponds 



7,000 



14'5 



36 



44 



3,330 

 11,758 



London 



10,000 



38 



48-5 



44 



Burke 



12,0C0 

 15,000 



36 

 63 



48-5 

 50-49 



44 



44 



11,139 

 20,294 



Avon 



Cordeaux 



15,859 

 21,411 



35 



50 



50-49 

 50 



44 

 44 



11,275 

 15.950 



Cataract 



Woronora 



7,565 



29 



50 



44 



9.251 



CHare's Creek 



2,000 



28 



44 



44 



7,860 



Prospect 



Totals 



5,502 











116,337 



348-5 



48-75 



44 



108,402 



Area of the lower Cordeaux 













Avon, and Nepean 













Rivers, draining into 













Nepean Tunnel at the 













Pheasant's Nest, and 













thence by the canal to 













Prospect Reservoir .. 





111 



36 



44 



25,494 



Area draining into the 













Woronora Tunnel and 













thence via the canal 













to Prospect Reservoir 

 Totals 





28 



38 



44 



6,78S 



116,337 



487-5 



4523 



44 



140,684 



The above estimate of discharge from average rainfall is a conservative 

 one, and is probably greater than the amount stated. Prospect Reser- 

 voir would probably be maintained by the drainage from the Woronora 

 Catchment Area alone. It will be seen, however, that any deficiency 

 would be made up from the drainage from the area of the lower portion 

 of the existing Catchment Area, namely, 111 square miles. There would 

 be, therefore, an amount equalling 20,000 million gallons annually going 

 to waste, which might be conserved by impounding it in a reservoir which 

 could be formed by a dam at the junction of the Cordeaux and Nepean 

 Rivers. 



The only other sources capable of affording so large an 

 additional supply as 80 million gallons daily within ten 

 years are the Wollondilly and the Cox Rivers, either singly 

 or combined, as they would be in the Warragamba. As 



