TNAG-0093-FCO40-129-Water-supplies-1968 — Page 132

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No. 2 Pinewood Close,

East Preston,

18 July, 1967.

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Dear Sir Arthur,

It was most pleasant meeting you again, since when I have given my estimate of 45 No. 18,000 ton ships to meet 1/3 of the 4 hour in 4 day consumption based on a 4 day R.K/Manila passage further thought in the light of the Admiralty signal you cabled at the end of our meeting. 2 days is of course correct and I feel we should adjust my assessment accordingly on the basis of 6 days (2 day passage, 1 day loading, 2 day passage, 1 day unloading) for the round trip. This does not include tanker cleaning time which must come out of the charter time.

My estimate of the 4 hour in 4 day demand is based on a 32 m.g.d. demand in 1963 increased at the compound rate of 10%. The 4 in 4 demand rate of increase I feel is higher than the rate for the 24 hour daily supply, hence the 10% rate suggested.

52 (1 + 10%)4

47 m.g.d. Let us assume 45 m.g.d.

The average carry of the 1963 tankers was 3 M.G, and I think should be assumed rather than the 4 M.G. quoted for the Admiralty Auxiliary Fleet Tanker, and in any case gives a "built-in" factor of safety. Thus the yield per tanker

3 M.G.

6 day round trip

0.5 m.g.d.

tabled

11 ?

thus requiring 30 tankers to yield 1/3 of the 45 m.g.d. estimated 4 in 4 demand, and not less than 5 berths at the H.K. terminal, 7 berths to take about 20,000 ton tankers were constructed in 1963. These berths might take larger tankers, but the advice of the Marine Department of the maximum size would be of value, especially in view of the tide rip, requiring berthing at slack water. It might be cheaper to provide some berths in the sheltered water on

TOLO the outside of Plover Cove main dam, or in Tob Harbour with the tankers pumping through the tunnel constructed to take the sea water pushed out of Plover Cove. The latter would impose a lower head on the tankers perhaps than the former, and both would be

lower than the heads of Sam Souen and Tower Wash. Lower heads

mean higher pumping rates, and faster turn round, Also if the Plover Cove water is of low salinity, higher salinity than

500 p.p.m. of tanker imported water would be diluted by that on Plover Cove, thereby placing less severe restrictions on the loading terminal.

:

However. Plover Cove must file (?) to the

LAST

RET

NEA

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lowest/