GooDnALL.— Water Supply for Auckland. 39 
provided always that experiments have satisfactorily proved them to be avail- 
able ; the cheapness with which they can be utilised, being so close to the 
proposed reservoir, and the waters being so pure, there will be no necessity for 
settling-tanks or filters. 
Having shown that Mount Eden contains a large quantity of water, and 
sketched a scheme whereby the samé might be proved and rendered available 
for supplying Auckland, I will now make a few remarks as to its sufficiency 
and probable cost. 
Supposing that the basin under Mount Eden would draw its supply of 
water from an area of about five square miles, and accepting twenty-four 
inches of rainfall as available, it will give the large yield of four million 
five hundred thousand gallons per day ; or, reducing the yield to one-fourth 
of that quantity to allow for any over-estimate of the area of the gathering 
ground—it being impossible at present, without boring and other investiga- 
tions, to determine the exact area of supply—there would still be left over one 
milion gallons per day, which would be more than sufficient to supply 
thirty-three thousand inbabitants with thirty gallons daily per head. These 
results depend entirely upon the depth and circumference of the basin, which, 
when ascertained, will give reliable data. 
It seems natural that by pumping at the centre of such a supply, before it 
had time to distribute itself, the full amount of rainfall percolating through 
the gathering area may be raised, and a larger quantity could be obtained than 
from a similar area at the Western Springs, or from those at Onehunga, where 
only comparatively small quantities flowing in particular directions can be 
used, the natural outlets being numerous. 
The cost of such a scheme would be less than one from Onehunga or from 
the Western Springs, as not only would a great saving be effected in transit 
pipes, but also in cost of pumping, as the water might be obtained at a 
considerably higher level than at either of the above-mentioned places. By 
examining the level of the outflow of the water at the Western Springs and the 
water standing in a well sunk by Mr Edgecombe—the distance between these 
two places being about a quarter of a mile—it will be found that the latter 
level is twenty feet above the former, which would give a rise to the 
centre of Mount Eden of about one hundred feet. This evidence is further 
corroborated by the large quantity of water obtained at a high level in the 
well of the Northern Brewery, on the Kyber Pass Road. 
The height to which the water would have to be lifted would be under two 
hundred feet, to a reservoir at Gilfillan’s corner, which point is nearly three 
hundred feet above the sea level. 
The cost of plant capable of raising a million gallons daily will be as 
follows :— 
