Environmental Engineering Reference
In-Depth Information
by energy-saving and environmental protection laws passed in the 1970s.
Utilities that once needed huge amounts of water to cool electrical gen-
erating plants now conserve water by recirculating it in a closed loop
(nonconsumptive use).
20
Consumptive use by power plants is only 2.5
percent of total water use.
21
Home Use
About one-fi fth of the nation's water use is in the home, so a signifi cant
part of the reason for our increasing water stress is the nearly universal
access Americans have to modern plumbing. Bathrooms are the major
users of water in homes, with dishwashers, present in 57 percent of
American homes, ranking second (table 1.4).
The use of water in our homes can be easily reduced. Toilets are a
particular concern, but water use can be reduced by more than 50
percent with the newer models that use less than 1.3 gallons per fl ush
rather than older models that used as much as 5 gallons (
table 1.5).
America is a fl ush-oriented society, but water use can be reduced by
adhering to the maxim, “If it's yellow, let it mellow. If it's brown, fl ush
it down.” Unfortunately, most Americans appear to want closure after
toilet use, and this can be provided by fl ushing. No-fl ush urinals have
been available for many years, but consumers have resisted them.
The silent toilet bowl leaks in American bathrooms are only slightly
less scandalous than the breaks in city water mains that lose 15 to 20
percent of the water piped through them (chapter 2). It has been esti-
Table 1.4
Allocation of water indoors in the typical American home
Use
Gallons per capita, daily
Percentage
Toilets
18.5
26.7
Clothes washers
15.0
21.7
Showers
11.6
16.8
Faucets
10.9
15.7
Leaks
9.5
13.7
Baths
1.2
1.7
Dishwashers
1.0
1.4
Other uses
1.6
2.2
Total
69.3
100.0
Source:
American Water Works Association, “Water Use Statistics,” 2010 Avail-
able at http://google.co.il/#hl=en&sourceehp&q=Allocation+of+Water+indoor
+in+the+typical+American+home.
