Water

Along the way, water is taken up by plants, animals and humans to be used for maintenance and growth. Humans annually withdraw 8% of the water in this global water cycle. On average, 8% of that water is used domestically, for drinking, cooking, bathing, washing, disposing of wastes, watering lawns and filling swimming pools. Twenty three per cent is used for industry, and 69% is used for agriculture. Developed countries use a larger percentage of the withdrawals for domestic and industrial use than developing countries do, but the changes come from increasing withdrawals, not from reallocating available water. While the average annual flow of rivers and the recharge of ground water generated by rainfall equals about 7,000 cubic meters per person, the water is not distributed uniformly over the planet, so some countries have less than 100 cubic meters per person while others have over 100,000.

Water shortages are so serious in parts of the globe that some rivers no longer reach the ocean because of withdrawals. The Colorado river is so depleted at the US - Mexico border, that the US pumps ground water into the Colorado to refill the river in order to meet our treaty obligations with Mexico - which promptly withdraws the water to meet its needs. The Yellow River in China also runs dry before it reaches the sea most months of the year, so the farmers in Shandong Province no longer have a reliable flow of water to irrigate their crops. Bangladesh and India feud over how much water is left in the Ganges when it crosses the border, and the only flow from the Nile into the Mediterranean is recycled irrigation water. As agriculture expands to feed growing populations, and industry expands to fuel economic growth, local water shortages are bound to become even more serious. The way water is used may aggravate shortages. In China, up to 11% of the rivers are so polluted by industry they are technically no longer suitable for irrigation. However, farmers may have no other water, so they use industrial waste water, and as a result rice and cabbage in some parts of China end up dangerously contaminated with lead and cadmium. Agriculture itself contributes to water pollution. Although banned or strictly regulated in developed countries, pesticides like DDT, lindane and toxaphene are manufactured and exported to developing countries for use in their agriculture, where they can contaminate local watersheds. And in developed countries, fertilizer and animal waste contaminate water with excess levels of nitrogen. Domestic uses can also cause problems. Untreated or poorly treated human sewage discharged into streams or rivers may contain pathogens or parasites that cause dysentery, cholera, typhoid or other diseases. Not only is the water unsuitable for drinking, but in some cases, it may not even be safe for irrigating crops. Nevertheless, because of local shortages of water, sewage is used and has been associated with endemic infestations of parasitic worms and with outbreaks of cholera and typhoid. Thanks to the water cycle, there will never be a global shortage of fresh clean water, but the ways we use and abuse water will continue to affect the local availability of usable water for hundreds of millions of people.

BioRegional Quiz: WHO begins courting this month?

Special Events/Information:

Job of the Month:

MU Meetings and Events (call to confirm times and places)

Organization Meetings and Events (call to confirm times and places)

Answer to BioRegional Quiz: Great Horned Owls and Barred Owls-listen for them calling.

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