Wednesday, April 18, 2012

Can We Use Less Water? World Water Crisis 101 (Part 3)

                       Parts one and two were posted yesterday

                                                        Conserving the Available Water Supply

Fact: Water use has been growing at more than the rate twice of population increase in the last century.
Source: Food and Agriculture Organization of the United Nations (FAO) and UN-Water

Yes, low-flow toilets and water-recycling shower-heads are good things. They should be perfected and installed as a matter of course. Yes, turning off the water while brushing our teeth is good and so are a the other personal water conservation tactics we adopt and environmentally-conscious global citizens and we should keep doing them. But domestic water use only makes up 8% of global water use. If we want to make a big water conservation impact, we need to address industry and agriculture.

Fact: The daily drinking water requirement per person is 2-4 litres [about 1/2-1 gallon], but it takes 2,000 to 5,000 litres of water [about 528-1320 gallons] to produce one person’s daily food.
Source: Food and Agriculture Organization of the United Nations (FAO)

More Food Using Less Water?

According to the FAO and World Water Assessment Programme of the United Nations, irrigating agricultural land increases crop yields by 100-400%. Those irrigated crops make up about 40% of global production. Unfortunately, “poor drainage and irrigation practices have led to waterlogging and salinization of approximately 10 percent of the world’s irrigated lands.”

Solutions such as drip irrigation, farm canals, and terrace agriculture have been shown to produce more food for less water, but are often at odds with increased mechanization and corporations of farms. Massive monoculture crops – huge fields of genetically identical plants that are easily sprayed with chemicals and irrigation water and harvested by machine – has been the trend in the United States and increasingly the world. Such farming can be water intensive and result in pollution devastating to rivers and streams near farms.

Farmers in the U.S. and elsewhere are making changes but much more needs to be done.

Different Foods Have Different Water Footprints
Changing what we eat can make a huge difference in global water consumption. Estimates vary, but there’s no question that, pound for pound, growing meat takes more water than growing vegetables, grains, or legumes.

Fact: It takes 1 000-3 000 litres of water [about 250-800 gallons] to produce just one kilo of rice and 13 000 to 15 000 litres [about 3400-4000 gallons] to produce one kilo of grain-fed beef.
Source: FAO

As global affluence rises, so does demand for western, meat-heavy diets. Heading off a global water crisis will most likely involve eating lower on the food chain. For information on how to start reducing your own meat consumption (perhaps even going vegetarian), check out the Meatless Monday campaign.

Industries, Governments, and Institutions Can Conserve Water Too

At 22% of world water use, industry could make a huge impact on global conservation. The same water-saving techniques used by households can yield big savings on an industrial scale. Optimizing industrial processes can save even more water. And for companies, saving water means saving money.

For example, in the late 1980′s, “Gangi Brothers Packing Company, a tomato processing and canning plant in Santa Clara, Calif., implemented several successful water conservation practices at its cannery, including the monitoring of operations to control water use and to identify areas where water could be saved.” The company cut their water use by approximately 61% and saved themselves nearly $40,500 per year (1990 dollars).

In 2009, a 9-year-old’s science experiment convinced the city of Reno, Nevada, to turn the water pressure down in all its public bathrooms.  Mason Perez showed science fair judges and city officials that hands got just as clean with plumbing valves closed half-way. The innovation cost Reno only the time required to reset the valves and saved taxpayers 20% on the city’s water bill.


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