The United States as a nation possesses abundant water
resources and has developed and used those resources extensively. The good news
about water is that “on average” the United States uses less than 8% of the
water that falls as precipitation within our borders annually. Unfortunately,
precipitation varies from the average significantly on a regional basis. With the exception of western, coastal regions
of Washington, Oregon, and northern California, the western United States is
arid and receives less annual precipitation than the rest of the nation, but
water use is no longer tied to local precipitation. For example California uses
4,470,000,000 gallons of water per day for domestic consumption alone; it also
uses 24,400,000,000 gallons of water per day for irrigation and would use more
if it were available.
Traditional water management in the United States focused on
moving or storing the country's abundant supplies of freshwater to meet the
needs of users. The era of building large dams and conveyance systems has drawn
to a close. The disruption of natural ecologies, environmental regulations, and
the sheer cost of building the massive water projects has made them impossible.
In the 21st Century, the regional limitations of the water supply and
established infrastructure must be managed more effectively to meet increasing
demands. "New" future supplies of water will come from conservation,
recycling, reuse, and improved water-use efficiency rather than from ambitious
development projects.
The future health and economic welfare of the Nation's
population are dependent upon a continuing supply of fresh uncontaminated
water. According to the US Geological Survey combined domestic private wellwater usage and public-supplied deliveries to homes totaled 29,400,000,000 gallonsper day in 2005, and “average” US citizen uses 98 gallons a day of water for domestic use, which includes, bathing and bathrooms, laundry, cooking, drinking and outdoor use. Outdoor watering in the drier climates causes domestic per
capita use to increase in the driest and hottest climates. In Nevada, average
domestic water use was reported to be 190 gallons/day per person, while in Maine
they used on average 54 gallons/ per day. We have the most control over the
amount of water we use in our homes and weather alone does not explain the
different water usage rates. In Maryland average domestic water use was reported
to be 109 gallons/day per person while in adjacent Virginia the average water
usage was 75 gallons/day per person. Pennsylvania to the north uses an average
of 57 gallons/day per person. The US Geological Survey who collected and
compiled all this data and the estimates imbedded in them offers no explanation
for the differences in domestic water use. While I believe there are differences in water
usage, I do not know the causes of the variation beyond the weather, but the
age of the water fixtures can contribute to the differences.
There are tremendous differences in water consumption of
appliances and fixtures based on their age and design. For example we all know
about low-flush toilets which use 1.6 gallons per flush versus 5 gallons per
flush for the older toilets. According to the 2001 Handbook of Water Use and Conservation by A. Vickers and
published by WaterPlow Press in Amherst, MA the average person flushes the
toilet 5.1 times a day. Before the advent of low flush toilet, flushing was the
largest use of water for each person. If you have new toilets your daily water
use for flushing would be 8.2 gallons versus 25.5 gallons for an older toilet.
Compressor assisted toilets (commonly used in highway rest stops) only use 0.5
gallons of water and if widely adopted could reduce flushing use of water to
2.6 gallons per day per person. Other toilets that have separate flush cycles
for fluid can also save water, and of course there is the California strategy
of not flushing after only urinating to minimize the daily number of flushes.
Changing your toilets and flushing behavior turns out to be the single most effective
water conservation strategy. Thank goodness, there are now powerful flushing
low flow toilets.
The typical American uses the most water for flushing,
showering, washing hands and brushing teeth, and laundry. Buying water
efficient appliances and fixtures and changing behavior can significantly
reduce our water use. For bathing and brushing teeth low flow faucets and
showerheads and behavior modification (not running the water while you brush
your teeth, shorter showers or not running the water while you lather up can
save about a third of the water typically used for personal hygiene, reducing
the typical 28 gallons a day to 19 gallons a day. Laundry is the second largest
use of water after toilets. According to Dr. Vickers the typical American does
0.37 loads of laundry per person per day. A top loading washing machine uses
43-51 gallons per load while a full size front load machine uses 27 gallons per
load and some machines have low volume cycles for small loads that use less. Replacing
a top load washing machine with a front load machine saves 6-9 gallons of water
per person per day or 24 gallons per load of laundry. A standard dishwasher
uses 7-14 gallons per load while a water efficient dishwasher uses 4.5 gallons
per load. Eliminating the watering of our ornamental gardens would
significantly reduce water use especially in the most arid parts of the
country where there is the most pressure on water supply. According to Dr. Vickers, by replacing appliances and fixtures with water efficient fixtures and eliminating outdoor use of water the typical American could reduce their water use to about 38 gallons per person per day. That is a significant water savings.
For people on public water supplies reducing domestic,
indoor water use saves money on the water bill. The average cost of water nationally
is reported to be under a penny a gallon, but that still adds up when you
consider that going from 98 to 38 gallons of water per day would save 21,900
gallons of water per person per year. For my household on well water the
concerns are different. My well draws fairly shallow for a Virginia well, my
pump is at about 100 feet. The aquifer is unconfined and the water level will
change with the seasons and drought. Natural groundwater levels usually reach
their lowest point in late September or October. The highest levels tend to be
during March and April, but this year was particularly dry until late April and
it remains to be seen if this will be a dry year. Groundwater levels usually
fall in May and continue to decline during summer as the trees and plants use
the available water. Many well owners are very conscious of our water use
because of the worry of the well going dry. Water conservation can help prevent
a well from being pumped dry and can be used along with scheduled use to live
with a low producing well.
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