Development & Aid, Environment, Headlines, Latin America & the Caribbean

ARGENTINA: A Crack in Dam Safety

Claudia Mazzeo* - IPS/IFEJ

BUENOS AIRES, Jul 27 2007 (IPS) - More than 500 dams around the world have collapsed since the mid-20th century. In Argentina, ageing and inadequate maintenance of dams built before the 1970s, the lack of coordination amongst regulatory bodies, and budget shortfalls are giving a boost to the latent threat.

Despite being a member of the safety committee of the International Commission on Large Dams, alongside countries that for decades have implemented safety standards for their major water projects, Argentina faces an uncertain future.

The participation of the federal government in the planning and construction of most of the country’s dams ensured in past decades their operational and structural safety, according to experts.

But the shift to the private sector of most of the hydroelectric dams combined with the absence or very limited intervention of regulatory bodies has left a deep crack that leaks much more than water.

“People understand that safety at nuclear plants is necessary, but they don’t have the same perception when it comes to hydro projects. When a dam breaks, the consequences can be immeasurable, and its impact can last decades, representing a catastrophe in loss of life and damage to property and the environment,” engineer Francisco Luis Giuliani, director of the dam safety regulating body, ORSEP, said in an interview.

ORSEP was created in 1999 to monitor Argentina’s privatised dams, which represent 30 percent of the total. But outside its jurisdiction are provincially-run dams, though they may seek technical assistance from ORSEP, and the governments of Mendoza, Salta, Jujuy, La Rioja and Córdoba provinces have signed agreements to that effect.

Argentina has more than 100 dams (nothing compared to the 40,000 dams in the United States) and half are for generating electricity.

Those with long memories talk about hydro-engineering’s glory days in Argentina, which produced the dams San Roque, Alicurá, Piedra del Aguila and Chocón, Florentino, Ameghino, and Salto Grande (a bi-national project over the Uruguay River).

Others gained notoriety because of politics, such as the Yacyretá, an Argentine-Paraguayan dam on the Paraná River whose cost, originally budgeted at two billion dollars, surpassed 10 billion dollars.

And then there is the other side of the story: since the mid-20th century, there have been more than 500 collapses of dams around the globe – some of which had high death tolls.

The collapse of the Panshet dam in India, claimed 4,000 victims in 1961. The failure of the dam on the Vaiont River in Italy killed 2,600 people in 1963. Brazil’s Oros dam collapse killed 1,000 in 1960. In the western Argentine province of Mendoza, 20 people were killed when the Frías dike collapsed in 1970 as the water ran too high for the design of the construction.

In 2000, a containment wall of the Anillaco dam in the north gave way, and gushed 500 to 900 million litres of water. Fortunately, only 100 of the 1,000 residents of the adjacent town were affected: they lost their homes or their fields.

“They were saved by a miracle. Even an engineering student would have designed it better. It had no embankment, no standards,” said Giuliani.

Piedra del Aguila, a dam for producing electricity, for irrigation and for controlling flooding of the Limay River, in the south-western province of Neuquén, did not claim any victims but did incur hefty repair costs in 1998 when small cracks developed and allowed water to pass.

Some years earlier, El Chocón, in Río Negro in the south, required 50 million dollars to patch the beginnings of a break in the embankment.

In Paso de las Piedras, in Buenos Aires province, the price tag was more than 30 dollars to repair a fissure at the core of the dam.

“Since the 1970s, (the dams) have been designed with appropriate safety factors with respect to the geotechnics of the sites, the materials used, and the designs and hydrology and structural calculations,” engineer Armando Sánchez Guzmán, technical director of the Paraná River Joint Commission, said in an interview.

“I have my doubts about the safety of the older dams (because) hydrology as a science underwent substantial progress after 1950,” he added.

“The international requirements underscore the need to plan the spillways of the dams for the highest probable water level, the result of the maximum probable precipitation, which is from a maximum probable storm, and finally transforms into a maximum probable flow or flood,” said Sánchez Guzmán.

Furthermore, the budget shortfalls affect the performance of the country’s techno-scientific agencies, and this sector is no exception, he said.

“The state of Argentina’s hydric works is very unbalanced, depending on the jurisdiction. Some are very well maintained, and others are not maintained at all,” ORSEP’s Giuliani told the 21st National Water Congress, held in May in the northern city of Tucumán.

“The Portezuelo Grande project, for example, the only system protecting the population from flooding of the Neuquén River, is in an unacceptable state,” he said.

Concepts of safety changed worldwide as a result of some of the dam disasters mentioned, said Giuliani. Not it is understood that safety does not only involve technical aspects, but also planning, the human factor, the organisation and the administration.

Large dams impose a threat that must be evaluated, he said. “In Europe and the United States there is specific legislation, where consideration of risk is obligatory.”

Argentina lacks “a safety law, a review of the state of all dams, national safety guidelines, and ensuring that dams and reservoirs meet internationally accepted standards,” Giuliani concluded.

(*This story is part of a series of features on sustainable development by IPS – Inter Press Service, and IFEJ – the International Federation of Environmental Journalists.)