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and irregularities on the downstream pitching had become more
pronounced, and also that the opening in the core wall con-
struction joint already referred to, had imcreased.
17.
Records of the leakage through the Dam have been kept
since December 1936, and had given no cause for concern up to
2nd September when the amount was approximately 43,000 gallons
per day part of which in all probability had not come through
the Dam at all, but had drained off the adjoining hillside.
18.
On 24th September however the leakage had increased
to 93,600 gallons per day and it was observed that an additional
discharge was issuing from a stone drain, which previously
had been more or less dry.
19.
As this discharge continued despite a dry spell of weather it was concluded to be leakage from the Dam.
Since
1st October this discharge has also been measured and the total leakage is estimated at present to be approximately 200,000 gallons per day.
20.
It is difficult at present to state whether the continuance of such a flow through the Dam may in time affect its stability. Should it remain fairly constant and no further movement occur during the next week or two, the question of lightening the load on the Dam by running to waste a percentage of the storage impounded may, I think, await Mr. Binnie's
arrival.
21.
It may be stated that the storage in the top 25 feet of the Jubilee Reservoir is 1,000 M. G. or 1/3 of the total
capacity of the Reservoir.
22.
The Gorge Dam seems to be in a satisfactory condition and the records being taken give no cause for apprehension. A portion of the pitching on top of the Dam is being removed in order that an inspection of the sand wedge may be made by Mr. Binnie.
(SD) A.B.PURVES.
8.10.1937.
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