The combination of excessive dam building, water diversion, irrigation of otherwise infertile land, and ground-water extraction, have all combined to lead toward siltation of reservoirs, soil salinization and serious aquifer depletion throughout the west central and southern United States. The present-day crisis was allowed to develop more or less unchecked through an unfortunate combination of “power-brokering” between the Bureau of Reclamation and the U.S. Army Corps of Engineers, exacerbated by lobbying on the part of economic interests, industry and politicians.
The result is a precarious balance of man-made checks and balances, consisting of the manipulation of such devices as dams, reservoirs, giant pumps, diversions and aquaducts in an ongoing effort to “improve” on Nature. These efforts have systematically given rise to unnaturally inflated human carrying-capacity expectations, which wreak havoc when the artificial support systems collapse. While heavily subsidized irrigation projects, such as the San Joachim Valley in California may initially produce high-value fruit and vegetable crops, often relatively low-value crops such as alfalfa are grown, which compete with their unsubsidized eastern counterparts. Further, the use of brackish groundwater, as well as recycling or re-using irrigation water, is increasing soil salinity in areas such as the San Joachim Valley and will eventually render it unsuitable for crop growth.
To fully understand the seriousness of the situation, you are advised to read Marc Reisner’s excellent book CADILLAC DESERT, (Penguin Books, 1987). In his book, Mr. Reisner states “ … Who is going to pay to rescue the salt poisoned land? To dredge trillions of tons of silt out of the expiring reservoirs? To bring more water to whole regions, whole states, dependent on aquifers that have been recklessly mined? To restore wetlands and wild rivers and other natural features of the landscape that have been obliterated, now that more and more people are discovering that life is impoverished without them?” … and again… “And it didn’t happen only in the West. Much the same thing happened in the East, especially in the South, where an incredible diversity and history and beauty in the old river valleys lies submerged under hundreds of featureless reservoirs. The vast oak and cypress swamps of the old South have been dried up, courtesy mainly of the Corps of Engineers, and converted to soybean fields (another crop of which we have an enormous glut).”
In his book Canada’s Water: For Sale?”, (James Lewis and Samuel, 1972) Richard C. Bocking describes how groundwater, accumulated over hundreds of thousands of years is being replenished at a far slower rate than irrigation pumps in the high plains of Texas are now removing it, with the result that water tables are dropping and in some cases the land is sagging. To encourage agriculture in areas such as this will simply accelerate the net loss of groundwater. The “Texas Water Plan” proposed bringing water from the Mississippi across the state to “rescue” the high plains. Costing many billions of dollars, such a plan would only encourage greater agricultural activity in a non self-sustainable area. To obtain the necessary water from the Mississippi River to make this plan work, would require the diverting of more water from the Great Lakes Basin through Chicago, into the Mississippi. To maintain water levels in the Great Lakes would then require diverting fresh water from the Arctic Watershed (see “Diversions” section)- a classic example of ecosystem interference and how human intervention invariably creates a never-ending “domino” effect.