 Good morning, John. A couple of weeks ago, you and I spent a little bit of time kayaking around a huge lake that, seemingly impossibly, is in the middle of a desert. And indeed, Lake Powell is not natural. It is the reservoir formed by Glen Canyon Dam. Now, there's a pretty good chance you don't know much about this, the second largest man-made lake in America, about the tremendous feats of engineering and human labor required to get it up and keep it up, as well as its fraught environmental legacy, contentious past, and limited future. I didn't really feel like mentioning any of this while we were enjoying it, but the fight that led to the creation of Lake Powell in some ways created the modern environmental movement and led to some aspects of that movement that I don't love. This marvel of humanity's ability, as well as our folly, is kind of one of my greatest internal debates made real, so I wanted to talk about that. Up until the 1960s, dams were a big win for pretty much everyone, especially in the arid southwest US. First, beautiful man-made lakes stocked with bass gave fun, easy recreational opportunities to millions of people. While getting into deep hidden canyons can be all but impossible for a hiker, motoring your boat into one is just a few gallons of gas away. Second, the tremendous water pressure that builds up behind tall dams like Glen Canyon Dam is also harnessed for energy, at peak enough to power two million homes without any carbon dioxide or other emissions. And most importantly, the Colorado River is a temperamental beast. A lot of water flows through the Colorado River, but season to season and even year to year, you never really know if it's going to be there when you need it to flush toilets or irrigate your crops. If states in the southwest were going to be able to grow their economies and populations, they needed a stable source of water and protection from massive floods. Hoover Dam, of course, created Lake Mead in the 1930s, but a number of other sites for dams became viable as technology progressed and the need for water increased. Three sites for large water storage projects included Echo Park, which would have flooded parts of Dinosaur National Monument, Bridge Canyon, which would have flooded parts of the Grand Canyon, and Glen Canyon. The fight between the Sierra Club and the Department of the Interior over these dams is stuff of environmental legend, and I encourage you to read about this era, it's fascinating. But in the end, Bridge Canyon and Echo Park were spared. Lake Powell was the price. This fight not only spawned much of the modern environmental movement, it also placed it within a frame that I personally find myself frustrated with sometimes, one of nature versus humans, and our technology. Like, the fact that we can see these canyons carved by the magnificent unstoppable power of this tremendously unstable river system and think, hey, we should control that is simultaneously the height of human effort and the height of human folly. I look at this dam and I think humans are so freaking amazing and also so freaking stupid. And indeed, these days, much of Lake Powell's water is lost to evaporation, water that would maybe otherwise make it to the sea to nourish the Gulf of California's Delta. The Colorado River almost always runs dry by the time America is done with it now. It has met the ocean just once in the last 20 years. And that's just the start of Lake Powell's problems. Fast-flowing rivers carry sediment, but when it hits the reservoir, the water slows down and the sediment falls out. Canyons are now filling with mud, as is the area behind the dam. In 100 to 150 years, the sediment will clog the outflow valves, and there will be no way to generate electricity from the dam. In 700 years, without some intervention, the reservoir will completely fill with mud. These days, drought has brought the reservoir down to just 50% of capacity, and there are fears that it will get much worse. And yet, that's far from the most severe possible problem, which is what happens when a dam exceeds 100% of capacity. We saw this this year when the Oroville Dam nearly failed when its spillway began to wash away, and it happened at Glen Canyon in 1983. Due to huge rains, dams upstream dumped so much water into Lake Powell that it kept rising even after all valves were open. The spillway began to wash away, leaving a 30-foot deep 80-foot wide hole in the bedrock of the dam. At times like those, I am reminded of the seemingly innocuous phrase, what goes up must come down. Someday, there will be no dam at Glen Canyon, and we can only hope that when that happens, we do it on purpose. And yet, I kinda love this dam. I love that I can kayak through those canyons. I love that these people have a beach that they can go to and fish to catch. I often see the environmental movement belittle the kinds of fun these people enjoy. The jet skis and the motorboats, and the imagining of nature is something that exists just to serve humanity. The environmental movement, I think, can go too far into imagining humanity, or at least those willfully ignorant humans, as nothing but a blight on the perfection of nature. Sometimes, this goes so far as to imagine all technology as a step in the wrong direction, as if the only way out of this mess is backward. But I cannot abide that. I am in love with nature, and I am in love with humans. I won't go so far as to say that we are natural, because while we are, we are also much more, and also sometimes I think less. I want Glen Canyon to be a natural, unaltered ecosystem, but I also want people to be able to enjoy Lake Powell. Part of being human is being able to want contradictory things. But I have been thrilled to watch, especially over the last decade, as technology has come to be seen more as a tool for the protection of the environment than for its destruction. These large-scale engineering projects that destroyed natural environments set up a dichotomy that's now being dismantled by electric cars and solar panels and LED light bulbs. But there are still times when I have to excitedly marvel at these amazing feats of human ingenuity, while also kind of wishing they didn't exist. I disagree with me sometimes, and especially in this particular moment in history when we are all so convinced of our own rightness and righteousness, I need opportunities to confront, admit, and accept that more than ever. John, I'll see you on Tuesday. While I was researching this video, I came across two documentary films that the US government made about Glen Canyon Dam, one about the construction, and one about the repair after the floods in the 1980s. And I found them both fascinating to watch, and if you are the kind of person who would like to watch those, I've uploaded them unlisted to the vlogber this channel, and you can do that by clicking on either of these links here. Okay, bye.