CHAIRMAN’S ADDRESS. XXXV. 
50 square miles, with a mean rainfall of probably not more 
than about 53 inches, it is considered doubtful in some 
quarters whether the reservoir will ever be filled. A study 
of this very interesting question, with the help of the 
Cordeaux River rainfall diagram, will I think convince any 
unprejudiced person, that the right step has been taken in 
building the dam up to the full capacity of the catchment 
area to fill it during wet seasons, so that it may be ready 
to assist us to contend with dry seasons for a longer time 
than would otherwise be the case. 
With the knowledge we now possess of the quantity of 
rain which runs off this catchment area, few people will 
doubt that had the smaller dam been constructed, an 
immense quantity of water would have been wasting tothe . 
sea, during a period such as was experienced from 1888 to 
1900, while during a dry period similar to that from 1900 
to 1907, it would have been empty the greater part of the 
time, assuming that it was being drawn upon to the extent 
of supplying the complement of 40 or 50 million gallons per 
day, which the city will soon be demanding, and Prospect 
reservoir would also have been drawn upon to exhaustion. 
The history of the Sydney water supply is full of interest, 
showing that provision not having been made during good 
seasons to improve the supply, and to prepare for the shor- 
tage which must eventually take place over an extended 
period of drought, the citizens have entered upon the dry 
seasons, badly equipped with the means of contending 
against them, and towards the end of the drought, which 
we know may last as long as 14 years, they have more than 
once been face to face with a water famine. 
It is not my intention to go further into the history of 
the building of the Cataract Dam, than to place on record 
the fact, that in addition to the inquiries already mentioned 
which took place before the work commenced, it became 
