108 Surface and Underground 



during sudden and heavy rains ; flooding the streets, inter- 

 fering with public traffic and private business, destroying 

 property, and causing vast and often-recurring expense to 

 the corporation in re-metalling portions of the streets, and 

 in removing the deposits of mud, sand, road metal, &c, 

 caused by these sudden inundations. 



The first of these objections can only be remedied by 

 underground drainage, and the second by intercepting the 

 storm waters before they enter the city so far as to occasion 

 loss of property or inconvenience to business, and it is to this 

 portion of the subject that I especially direct attention in 

 this paper. 



Any one at all acquainted with Melbourne will be aware 

 that the outlets for the surface water are the open street 

 sewers ; on the ' south, crossing Flinders-street at right 

 angles, at Russell-street, Swanston-street, Elizabeth-street, 

 Market-street, and King-street ; and at Little Bourke-street 

 on the west : and my principal object in this paper is to 

 show the relative amount of water carried off at each outlet, 

 the area it drains, and to suggest a plan for preventing floods 

 in the principal business parts of the city. 



Ten years ago it seemed to me not only desirable, but 

 essentially necessary, to prevent the various floods that 

 occurred in Elizabeth and Swanston-streets, by intercepting 

 the waters at the north boundary of the city, and conveying 

 them by means of a tunnel into Batman's Swamp. Subse- 

 quently, I brought the subject before the Philosophical 

 Institute, in a paper read before that Society on the 4th 

 March, 1857, and in another paper " On the Reclamation of 

 Batman's Swamp," read before the Philosophical Institute on 

 the 5th May, 1858, and published in Vol. III. of their 

 Transactions. 



I now bring this suggestion again forward in a more 

 practical shape, and to determine how far it would answer 

 its intended purpose, I have made a survey of the entire 

 area drained by the open channels to the south and west of 

 the city, avoiding any particular reference to the main 

 channels that carry off the storm water falling upon the 

 various suburbs, except so far as those that pass through the 

 city itself. 



The proper consideration of this subject renders it neces- 

 sary to ascertain, as accurately as possible, the amount 

 of rain that falls during the year, and more particularly the 

 maximum quantity that has fallen in any given time, as it 



