  
 Around the world, the exploitation of water resources in the recent past has caused major disruption to hydrological cycles. It's a complicated problem: (1) - water development for agricultural, industrial & residential use is reducing river levels, depleting wetlands & draining down aquifers. (2) - global warming is causing thousands-years-old ice sheets (which feed our rivers & aquifers) to melt past the point of stability. (3) - our heavy water demands -- coupled with deforestation in important watersheds and rising global temperatures -- are destroying the systems we depend on.
Two alarming examples, both in the West, where water depletion has become a sudden and unreputable issue, are the relatively small Denver Basin and the much larger High Plains aquifer.
Please read our short synopses:
I. Douglas County, A Suburban Area Outside Denver, Colorado
In 1970, 12,000 people lived in Douglas County, Colo., just south of Denver. Today, more than 200,000 people reside there, with the population expected to double in the next 25 years. Like other counties in the Denver area, Douglas County relies on 10,000-year-old groundwater from aquifers located in the Denver Basin for its water supply. However, due to rapid population growth and economic development, the region's local water supplies are literally being sucked dry and citizens now face a dire reality: “There is a finite amount of groundwater in this aquifer system,” says Robert Raynolds, a geologist at the Denver Museum of Nature & Science.
Presently, the aquifers that sustain this suburban area are dwindling at average rates of 30 feet per year. In Castle Pines North (Douglas County) water wells are dropping at an average of 34 feet every year. In individual wells across Douglas County, water yields have already slipped from 500 gallons per minute to 100 gallons per minute (leaving bathroom showers with barely a trickle).
The local South Metro Water Supply Study Board has created a long range solution. The plan is to build pipelines between Denver and this south metropolitan area, which would transfer large amounts of water and subsequently store it in newly constructed, man-made resevoir facilities. The plan, however, is estimated to cost $3 billion between now and 2050 and will have unknown disruptive effects on local eco-system relationships. A second plan — drilling more and deeper wells — is estimated to cost closer to $4 billion by 2050. In any case, the costs for either of these operations would be passed on to consumers. And, in the first plan, average "tap fees" (the price levied on new service lines or wells) might rise as much as 100 to 500 percent. Tap fees in the second plan, drilling more and deeper wells, could increase by as much as 700 percent.
With water supplies disappeaing, the region is in trouble.
II. The High Plains Region - "America's Heartland"
America's rich "breadbasket" is fed by a single aquifer system, which spreads below 111 million acres of land, encompassed by eight states. Since the 1940s, widespread groundwater pumping of the High Plains aquifer has led to the reliable production of millions of tons of corn, wheat, sorghum and other crops. From this region, America literally feeds the world. But the water resource is rapidly dwindling -- threatening the livelihood of these western states and the future of American food stability.
According to the US Geological Survey report (2004), the High Plains aquifer has lost about 6 percent of its stored water since the 1940s. But this figure is misleading. Some of the regions fed by the aquifer may soon contain no economically recoverable groundwater whatsoever and will thus fall into decline, possibly echoing or even exceeding the severity of the great American Dust Bowl era.
Total measured losses indicate about 200 million acre-feet (equivalent to approximately 65.2 trillion gallons — about as much as California’s annual rainfall) have been permanently drained from the system so far.
Degrees of "wear and tear" -- aka depletion, vary depending on location. The largest losses of groundwater have taken place in Texas and Kansas. In Texas, the High Plains aquifer has 27 percent less water than it did only 50 years ago; Kansas’ portion now stores 16 percent less. Lubbock, Texas -- one of the areas whose farm-oriented economy and ecological stability has been hardest hit, has used up at least half of the aquifer’s local groundwater in just the past 50 years.
The pumping is not sustainable.
Additionally, one should keep in mind that disrupting the balance of any aquifer's drawdown levels will likely lead to disruption of water purification systems. Human-made wells ideally draw water from the cleanest and most productive zones within an aquifer. But decreasing an aquifer’s saturation can affect the water within reach of human-made wells and pumps.
For example: In the High Plains system, “Water that did not previously discharge from deeper units [of the aquifer] might [now] do so,” says Kevin Dennehy, USGS project manager of the High Plains Regional Ground Water Quality study. The result of mixing unbalanced and unfiltrated waters brings more unprocessed chemicals and/or salts to the surface, and water quality suffers. Dennehey continues, “the upper part of the [High Plains] aquifer is [also] vulnerable to the effects of human activities,” such as the application of pesticides or other chemicals, which travel into an aquifer via runoff and recharge.
Summary: Draining down aquifers not only stresses local and large scale ecological cycles, it weakens an aquifer's ability to filter its own water and makes it vulnerable to contamination from human-made materials. Without abundant, balanced-system water supplies -- we all suffer.
Let's all keep this from happening. Let's Shop Water Efficient!
-- Good Common Sense.
ABOVE CONTENT TAKEN FROM: THE UNITED NATIONS ENVIRONMENTAL PROGRAMME: {{http://www.unep.org}} and "WESTERN AQUIFERS UNDER STRESS", GEOTIMES MAGAZINE, THE OFFICIAL MAGAZINE OF THE AMERICAN GEOLOGICAL INSTITUTE: {{http://www.geotimes.org/may04/feature_westernaq.html#denver}}
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