Dietetic purposes (cooking, drinking, &c.) 1
Cleansing purposes (washing house utensils,
clothes, &c.) 6

If water-closets are in general use, add 3

If baths are in general use, add 5

Total 15

It therefore follows that the quantity of domestic sewage to be
expected will vary from 7 to 15 gallons per head per day,
according to the extent of the sanitary conveniences installed
in the town; but with the advent of an up-to-date sewage
scheme, probably accompanied by a proper water supply, a very
large increase in the number of water-closets and baths may
confidently be anticipated, and it will rarely be advisable to
provide for a less quantity of domestic sewage than 15 gallons
per head per day for each of the resident inhabitants. The
problem is complicated in sea coast towns by the large influx
of visitors during certain short periods of the year, for whom
the sewerage system must be sufficient, and yet it must not be
so large compared with the requirements of the residential
population that it cannot be kept in an efficient state during
that part of the year when the visitors are absent. The
visitors are of two types--the daily trippers and those who
spend several days or weeks in the town. The daily tripper may
not directly contribute much sewage to the sewers, but he does
indirectly through those who cater for his wants. The resident