I finally got to bed around 1:30, so 4:30 came very quickly. We got on a bus for the five hour trip to Itaipu dam and all of us slept most of the way. I did a little reading and watched some of the countryside, but it was mostly agricultural land that, apart from the red soil and local trees, could have been mistaken for my rural childhood home. When we arrived at the dam we got an animated and eccentric tour guide that people seemed to enjoy, and a translator for Chan and I. The dam is incredible. While not the biggest dam anymore (Three gorges has eclipsed it) Itaipu still produces the most power in the world because of the year round water supply. Ten percent of the production produces all of Paraguay’s power and the rest fulfills 20% of Brazil’s power needs. It actually approaches 1% of the total world’s power production. It is an impressive and seemingly improbable edifice.
Today the spillway was spilling. At current flows, the dam can only use about half of the water for generation and has to spill the other half (to keep a safe pool elevation). So about 300,000 cfs (50% more water than flows over Niagara Falls in a given day) was flowing down the spillway.
This generated vortex dynamics at the downstream end of the spillway that I had never seen. It was like some sort of science fiction special effect. We all had to take off our name badges because they would get sucked into it.
The dam was amazing. It is a joint Brazilian and Paraguayan project, so at one point in the tour we crossed over into Brazil for 90 seconds. This poses the question: Have I now been to Brazil? It doesn’t really fit my criteria for claiming to visit a country or state (which is having a meal outside of the airport). Afterwards we went to the physical model of the dam. I have seen a number of very large physical models, but I have never seen anything quite like this. The downstream model extended about 200m below the dam. The model was in mild disrepair, but they have just awarded a contract to refurbish it to investigate the potential for inline turbines.
After the model we went to the “zoological park.” This is basically just a zoo for now, but there are plans to expand it into something much more dramatic. This is part of a new “holistic watershed approach” that the powers that be have been perusing since about 2003. The dam flooded a lot of habitat for the dense biodiversity that had little to work with before. Now, I have written before about how much I like zoos, especially zoos that specialize in local species…but my new ecology background makes me much less hopeful than the guide that the attempts at mitigating diversity losses . The story of the great contemporary extinction event is pretty grim. Many of these creatures are not just endangered but doomed, as their genetic material and required habitat structures have been irrepribly lost (a phenomenon known as extinction debt – where the animal has not yet been lost, but the damage is irreversible).[1] None the less, it is very encouraging to hear talk about holistic management, and not only species diversity but allelic diversity.[2] Also, there were a half dozen pigs that are the only known population of that species extant, and they were thought to be extinct for 30,000 years.
[3]
After the zoo, we stopped by a waterfall. Now, they charged a dollar to get in, so I was not expecting a lot, but the falls we saw were comparable to Letchworth, the grandest sight in western NY. At that point I though, Hmm, if I knew we were going to see this, I wouldn’t have paid to see Iguazu falls tomorrow (but I didn’t really know what I was talking about…more on that in a couple posts).
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[1] Conservation ecology gets pretty grim. The field is pretty pessimistic (I am going to write about this a little next week in my main blog ). I guess this is why I am a “restoration ecologist.” It might be Quixotic, but the restoration crowd strikes me as a much more hopeful crowd. The very task of trying to reverse processes, even while the rate of damage far exceeds the rate of restoration, seems to change the outlook.
[2] Avoiding the genetic degredation (e.g. the Florida panther which is essentially inbred to the point of imbecility) the minimum sustainable population size
[3] Known only from the fossil record.
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