202 



Report of the Commissioners on the 



Loss from evaporation over surface of water in reservoir, 

 at the rate of nine feet deep, on asuperficial extent of 1,460 

 acres, equal to 21,199,200 cube yards. 



Which amount of evaporation, deducted from the total of 

 supplies in reservoir, will give the amount of water available 

 for consumption, equal to 22,019,412 cube yards. 



This total result is equivalent to 101|- gallons per head 

 per day, for a population of 100,000 persons. 



Before concluding this report, we feel It our duty to 

 represent the deterioration of the Plenty water, owing to the 

 passage of its western and eastern arms through the swamps, 

 we tasted the water above and below the swamps, in the 

 former case it was perfectly clear and refreshing, and free 

 from impurities, as coming from the rock, while below the 

 swamps it had a flat unpleasent taste, and was not nearly so 

 pure as that above the swamps ; this deterioration of the 

 water might have been avoided if the site of the reservoir had 

 been chosen above the swamps, on the eastern arm, while the 

 western arm might have been left to supply the settlers, the 

 reservoir could be formed by the construction of a short dam, 

 at the junction of Jack's Creek with the eastern arm, which 

 would store nearly all the catch of the eastern arm above the 

 swamps, equal to fifteen square miles, thus giving nearly 

 17,000,000 cubic yards, with a loss from evaporation on 

 about half a square mile of reservoir surface, equal to 

 4,600,000 cubic yards, leaving 12,400,000 cubic yards, equal 

 to fifty-seven gallons per head of pure delicious water, fresh 

 from the rock, available for the supply of Melbourne, instead 

 of 22,000,000 cubic yards of indifferent water, as in the 

 present reservoir. 



As it is now too late to adopt this scheme (and thereby 

 avoid the loss by the evaporation of 21,000,000 cubic yards 

 in the present reservoir), we are of opinion that the eastern 

 and western arms of the Plenty should be diverted from the 

 swamps through which they pass, by means of open cuts, 

 carried round same, the water would thereby be conveyed 

 into the reservoir as pure as from the ranges, and the loss 

 from the swamps, or 4,194,805 cubic yards being hence 

 avoided, would be added to the reservoir supply, making in 

 all 26,214,217 cubic yards, equal to 121 gallons per head per 

 day. 



We have now had the honour of submitting our views on 

 this important inquiry, and in conclusion beg to express a 

 hope that the limited materials, in the form of data, local 



