Dam Trouble

 

Hoover Dam

It can be said that large dams like Hoover Dam on the Colorado River and Bonneville Dam on the Columbia River boosted the United States to superpower status by enabling its industrial might to spur the Allies to victory in World War II.  Hydroelectric power from these two dams powered the industrial plants in Los Angeles and Seattle that built warplanes and ships, the military hardware that won the war.  Cheap electric power also fueled the American Dream as every household either filled their homes with labor saving electric appliances or dreamed of doing so.

The American Dream according to GE

Indeed, imagine Las Vegas which is only 30 miles from Hoover Dam if the dam had never been built.  Not only is Sin City or The Entertainment Capital of the World, if you prefer, dependent upon the dam’s hydroelectric output, but roughly 90% of its water comes from Lake Mead cached behind the dam. 

The spectacular success and phenomenal growth of Los Angeles, Southern California and Las Vegas have fueled the conventional wisdom that these dams were well worth the investments in them – in dollars spent, lives lost during construction, and ecosystems destroyed in their path.  Both of these dams were built in the 1930s.  Large dam construction peaked in the early 1970s.


During that 40 year span, the best dam sites were built upon and the world began to experience the massive destructiveness of large dams.  Nevertheless, there are more than 45,000 dams spanning 60% of the world’s major river basins, and the water backed up behind them covers more land than the State of California. Yet, nary a year passes without new dam proposals to ponder.

The World Bank Ignores Itself

It should be emphasized that dams are much more destructive than their proponents would have us believe.  A curious flip-flop unfolded in the early 2000s as the World Bank created the World Commission on Dams to blunt criticism of its lending policies to third world countries who were buying dams at their behest – at great expense and dubious benefit.  The Commission aired its long awaited report in November of 2000 with a special keynote speech by Nelson Mandela.  The report was titled Dams and Development:  A New Framework for Decision-Making.  Among its findings, which the World Bank has chosen to ignore:  

·         Environmental impacts of large dams are more negative than positive; have, in many cases, led to irreversible loss of species and ecosystems;

·         Irrigation dams typically do not recover their costs, did not produce the volume of water forecast and are not as profitable as forecast;

·         Large dams have led to the impoverishment and suffering of millions;

·         Large dams tend to sustain schedule delays and significant cost overruns; and

·         Large dams, particularly shallow tropical dams, contribute to global warming by emitting greenhouse gases released by vegetation rotting in reservoirs and carbon inflows from watersheds.

International Rivers Network

To understand the technical, scientific pitfalls presented by dams one should visit www.internationalrivers.org.  Some of the problems they describe with great clarity are:

·         Dams prevent nutrients from flowing to the deltas, the floodplains, where they benefit the soil, fisheries and marine life in general;

·         Dams trap all the free flowing silt that is carried by a river’s turbulence;

·         Salt once carried to the ocean by undammed waterways is deposited in concentrated form on irrigated lands-- slowly poisoning the soil; and

·         Dams diminish the ocean’s ability to absorb CO² by curtailing the nutrient plume that fertilizes phytoplankton that therefore die and sink to the ocean floor encapsulating the carbon for the long-term.

Dams Are Not Forever

Both the World Commission on Dams and the International Rivers Network state that dams contribute to global warming.  This conflicts with conventional wisdom which assumes that fossil

fuels are the only culprit in climate change, and that hydroelectric power is clean.  Clean or not, it has

been reported that 30 – 70% of California’s Sierra snow pack will disappear this century. California’s 1000 dams will face greater pressure from flooding as glaciers melt, making them potential hazards to millions of people living downstream.  On the other hand, once the snowpack

Snowpack in Sierra Nevada

vanishes, the dams will be obsolete anyway.

Dams and levees can never be fail-proof, and when they fail, they do so spectacularly and sometimes catastrophically.  They also provide a false sense of security that encourages risky development on vulnerable floodplains.  Think of New Orleans in 2005.

The alternative to relying on dams for flood control is flood risk management which assumes that floods will happen and that we need to learn to live with them as best we can.  Effective flood risk management reduces their speed, size and duration where possible, while it protects our most valuable assets, and situates them out of a flood’s destructive path.  Flood risk management assumes that all flood protection infrastructure can fail and creates plans for recovery. This alternative recognizes that all floods are not inherently bad – and indeed that floods are essential for the health of riverine ecosystems.

In the end all dams will die.  They are not permanent or eternal.  They topple over, are dismantled, fill with sediment or lose their financial rationale.  Assessing the cost of erecting a dam should include the cost of safely decommissioning it to prevent catastrophic destruction downstream if they fail. That cost must also include funds to maintain aging dams whose maintenance costs rise as time passes.

Alternatives to Damming the Planet

At the top of the list is conservation.  Conserving water speaks for itself.  Although the amount of precipitation can vary from year to year, the earth has a finite amount of water which cannot be increased.  A very brief and painless internet search will yield over 100 tips on how to save water so I won't belabor the point here.  Every little bit helps.

Reducing the impact of our use of energy also reduces our reliance on hydroelectric power.  While our sources of energy must be made cleaner, our first priority must be to use energy more efficiently.  Efficiency turns out to be cheaper, cleaner and faster to install than any other energy option.  Efficiency is not only cheaper than all other energy options, it also leads to growth in personal income, because lower energy bills free up money that can be spent elsewhere.

Up to 75% of the electricity used in the US today could be saved with efficiency measures.  Developing countries, which will account for 80% of global energy demand growth to 2020, could cut their demand by more than half using existing technologies to improve energy efficiency, according to the McKinley Global Institute.  “This would leave energy consumption some 22% lower than it would otherwise have been – an abatement equivalent to the entire energy consumption of China today,” the institute states.

                                                   Read more at www.internationalrivers.org.

A very good read . . .

Deep Water, The Epic Struggle over Dams, Displaced People and the Environment by Jacques Leslie, Copyright ©2005   Farrar, Straus and Giroux