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In a paper like this it is only possible to discuss the topic in general terms giving some
local illustrations of some of the problems. Other ports and shipping companies undoubtedly
have varying practices and experiences. I trust that we will learn of these during the discussion.
Sources of Supply
Fresh Water. The sources are, of course, the town mains in ports throughout the world. There
is little need to expatiate on this. Pure supplies are now readily available on most shipping
routes. Companies usually have ports of choice for water supplies which they regard as pure,
taking precautions with any water taken perforce elsewhere.
It is the duty of the Medical Officer of Health to keep a check that the water as delivered by
the quayside hydrants in the Port Health District is safe. When a supply main is accidentally
damaged the resulting pollution can be gross. This occured in the Port of London a few years
ago. a dock hydrant, which had hitherto yielded consistently "good" samples, suddenly shewed
Escherichia Coli contamination exceeding a count of 100 per 100 ml. Flushing of the supply main
and chlorination did not remedy the impurity. The pipe had to be exposed. It was found to be
fractured where it ran in earth below the level of the nearby dock water. This combined with the
fluctuating pressure in the main accounted for the exceptionally high degree of contamination. To
prevent recurrence of such an incident the main can be laid in a prefabricated concrete conduit
parallel with the sill of the quay. The conduit has ample means of inspection and cleansing and
is suitably protected at the hydrants.
Sea Water. It is perhaps superfluous to refer to the source of sea water in relation to ships and
I do so only to draw attention to its subsequent conversion into distilled water and the problems
sea water can produce are dealt with under the appropriate later headings of this paper.
Distilled Water. In addition to boiler supplies, distilled water is used to supplement the stored
fresh water in many ships. One of the major factors in the early struggle to gain control over
water borne disease, distillation is still widely used. The choice, however, is now made for
reasons other than the provision of a pure water supply. Motor ships are naturally less likely to
favour distillation than steam ships. Other determining factors are the time between ports and
the economic value of the space that fresh water storage occupies when compared with the cost
of producing distilled water.
Transfer of the Supply
Direct
Sea Water. This in itself presents no special problem except in relation to the time and place
of usage. There is no Regulation against the use of sea water while a ship is in dock, river or
other polluted place. There is a clear warning against such usage in a Ministry of Transport
Notice, but the Handbook for the guidance of Shipowners has merely a recommendation that the
salt water supply to a galley should be fitted with a stop cock with locking arrangements. It is
also only recommended that a salt water intake should be situated forward of, and on the opposite
side of the ship to any sanitary discharges. Beyond these specified, but apparently merely permissible
dangers is that of the accidental introduction of sea water into the fresh water supply.
Fresh Water. The transfer of water by hose from a hydrant on the quay to a filler pipe on deck
would appear a simple matter, but all too often it has led to the pollution of the supply. In 1960
the co-operation of the Port of London Authority was obtained for the introduction of a "Code of
Practice" for the supply of fresh water from shore to ships. This has resulted in supplies as
delivered on board being regularly of "satisfactory" or higher standard (84% "excellent").
The Code covers all the points relative to equipment, handling and supervision. The Code is
reproduced at the end of this paper so perhaps it will suffice to consider only those points
brought out by the following two incidents. The first involved a ship which always maintained a
reservoir of fresh water for fire fighting purposes. Its supply line was coupled directly to a hydrant
on the drinking water main ashore by a closed connection to the fire fighting storage tanks.
As the intake of fresh water seemed to be proceeding satisfactorily, even though slowly, it was
left unattended for some time. The hydrant was one of several on the same main in which the
pressure varied with the simultaneous demands of neighbouring ships. The fire fighting system
having been completely filled, a subsequent fall in pressure of the mains supply, resulted in a
reverse flow and contamination of the drinking water mains, This illustrates the danger of the
closed connection and draws attention to the one point in the Code of Practice that it has not yet
been possible to implement in full. This is the provision of a non-return device on the supply
equipment. This matter has been deferred for the present owing to considerations of water pressure
and the finance involved.
In the second incident a large passenger liner was involved in which a considerable proportion
of the crew remained on board while in port. This ship had two fire-fighting systems; one
on a high pressure installation and the other a fresh water sprinkler system. Both had a stop
valve fitting on the superstructure. The deck connections were not far removed from one another
and it was customary to connect the sprinkler system to the drinking water supply from the shore
to ensure a continuous supply in case of emergency. Unfortunately the fresh water hose was
close-connected to the high pressure fitting by mistake and the stop valve opened by a careless
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