118 Surface and Underground 



These enormous volumes of water, principally falling out- 

 side the City, pass, on their way to the Yarra, through the 

 very busiest of our streets, namely, Elizabeth and Swanston- 

 streets, and flood the same to such an extent as to prevent 

 traffic of any description. 



The size of the open channels in Swanston-street, and the 

 contour of that street, will not admit of the channels carry- 

 ing off the whole of the water, and from its being higher than 

 Elizabeth-street, a very large amount of water overflows 

 down Bourke-street, Little Collins, and Collins-streets into 

 Elizabeth-street, augmenting the flood in that street to such 

 an extent as to make it dangerous alike to life and property, 

 irrespective of the great damage done to the streets them- 

 selves. 



The question now comes before us, by what means and to 

 what extent can these floods, so fatally affecting life and 

 property, be prevented 1 



With respect to the means of prevention. Referring to 

 the plan I now submit : the dotted line shows the position 

 of the tunnel I suggest being made to relieve the City proper 

 from such floods, and runs, as you will observe, from the 

 intersection of Stephen and Lonsdale-streets along Lonsdale- 

 street to the Hospital corner, then bears north to Latrobe- 

 street, and west to Batman's-swamp, making a total length 

 of 3 09 chains. 



This tunnel could be constructed without interfering with 

 private property, and be at a sufficient depth beneath the 

 level of the streets. 



I have taken the levels at the various points, and I find 

 that there is a fall of 47 feet between the surface level of 

 Elizabeth-street at Latrobe-street and low water in the Yarra 

 below the falls, and that the fall between a point at the 

 Hospital corner of Swanston-street and low water level is 

 5619 feet. There is also sufficient fall in Lonsdale-street, 

 between Stephen-street and the Hospital corner. 



It will thus be seen that there is a sufficient fall to give 

 the most desirable inclination to the tunnel or underground 

 sewer. 



The material excavated in the construction of this tunnel 

 could be used with great' advantage in the reclamation of 

 the low swampy ground lying between the railway and the 

 western end of Latrobe, Jeffcott, Franklyn, and Dudley- 

 streets, and the firm ground thus made would not only assist 

 in the expense of constructing the tunnel, but would also 



