344 ENVIRONMENTAL HEALTH
TABLE 4
Guides for water useType of establishment Gallons per daya
Residential:
Dwellings and apartments (per bedroom) 150
Temporary quarters:
Boarding houses 65
Additional (or non-resident boarders) 10
Camp sites (per site) 100
Cottages, seasonal 50
Day camps 15–20
Hotels 65–75
Mobile home parks (per unit) 125–150
Motels 50–75
Restaurants (toilets and kitchens) 7–10
Without public toilet facilities 2 –3
With bar or cocktail lounge, additional 2
Summer camps 40–50
Public establishment:
Boarding schools 75–100
Day schools 15–20
Hospitals (per bed) 250–500
Institutions other than hospitals (per bed) 75–125
Places of public assembly 3–10
Turnpike rest areas 5
Turnpike service areas (10% of cars passing) 15–20
Arusement and commercial:
Airports (per passenger) 3–5
Country clubs 25
Day workers (per shift) 15–35
Drive-in theaters (per car space) 5
Gas station (per vehicle serviced) 10
Milk plant, pasteurization (per 100 lb of milk) 11–25
Movie theaters (per seat) 3
Picnic parks with fl ush toilets 5–10
Self-service laundries (per machine) 400
Shopping center (per 100 sq ft fl oor area) 250
Stores (per toilet room) 400
Swimming pools and beaches with bath-houses 10
Farming:
Livestock (per animal)
Cattle 12
Dairy 35
Goat 2
Hog 4
Horse 12
Mule 12
Sheep 2
Steer 12hydrologic or water cycle shown in Figure 3. The average
annual precipitation in the United States is about 30 inches
of which 72% evaporates from water and land surfaces and
transpires from plants, and 28% contributes to the ground
water recharge and stream fl ow.^17Water QualityWater quality is usually determined by the water source, the
treatment it receives and its method of distribution. Standards
of water quality take into consideration the physical, chemi-
cal, and microbiological characteristics, the radioactivity, and
compliance with the Public Health Service Drinking Water
Standards 1962.^18 Interpretation of water quality analyses
should be based on a sanitary survey. This is defi ned as “(1) An
investigation of any condition that may affect public health.
(2) A study of conditions related to the collection, treatment,
and disposal of liquid, solid, or airborne wastes to determine
the potential hazard contributed from these sources to the
environment. (3) A study of wastewater discharges on sources
of water supply, on bathing or other recreational waters, on
shellfi sh culture, and other related environments.”^19
Surface waters by their very nature are subject to natural
and manmade pollution which in many instances is not read-
ily controllable. Hence the selection of a surface water supply
source must take into consideration the treatment that may be
needed now and in the future to ensure that the fi nished water
will at all times meet the Drinking Water Standards. It is obvi-
ous that this objective can be met with greater certainty if the
source of water is from a protected watershed and reservoir
rather than from a stream passing through urban areas which
may also be used for wastewater disposal and navigation.
Raw water quality criteria for public water supplies have
been developed which recognize the great variability in surface
water quality. The criteria are shown in Table 3. The permissible
criteria are for raw waters which can by conventional rapid sand
fi ltration treatment or less meet the Drinking Water Standards.
The desirable criteria are for raw waters which can meet the
Drinking Water Standards at less cost and with greater factors
of safety than is possible with waters meeting the desirable cri-
teria. It is important to point out that the constituents marked
with an asterisk in Table 3 are not removed by conventional
rapid sand fi ltration treatment. In some instances additional
treatment with coagulant aids or activated carbon may suffi ce,
and in others elimination of the source of the contaminant may
be the only practical answers.TABLE 4 (continued)
Poultry (per 100)
Chickens 5–10
Turkeys 10–18a Per person unless otherwise stated.
From Rural Water Supply, New York State Department of Health, Albany,
NY, 1966.C005_009_r03.indd 344C005_009_r03.indd 344 11/18/2005 10:24:47 AM11/18/2005 10:24:47 AM