More Interesting Dam(n) History :-)
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JFRCalifornia
Keeper of San Juan Secrets
That was a really interesting documentary, thanks for sharing! Besides the unbelievable engineering that went into the project, there's a certain sadness watching it too, especially the part where they finally stop the river...
The most interesting part though was at the end, when Chet Huntley laid out predictions of massive new urban areas that would result from the dam's presence, and that the lake would be filled in 5 years. Neither proved to be true (modern Vegas and Phoenix would have happened anyway without Glen Canyon Dam). It is true that the lake helped regulate flows into Lake Mead, which indirectly helped the reliability of the future Central Arizona's Project ability to provide water to Phoenix and that state in general... It also ironically helped the river rafting industry in the Grand Canyon, since the flows became more predictable and allowed for longer seasons... and of course certainly created a great recreation area... but not without some unforeseen environmental consequences, which in hindsight now seem obvious...
But the 5-year prediction to fill the lake was something I hadn't heard before. The reality was 17 years. Makes you wonder why they were so far off in that prediction. And yet it only took 7 years to fill it to a level we'd recognize today as "normal"--in 1970 it finally hit 3600... but from there it took another 10 years to fill the last 100 feet, and that only happened because of two massive years in the 1970s (1973 and '79) mixed in with a lot of up and down ones... The most crucial factor that allowed Powell to fill was that Lake Mead was about 100 feet higher than today, so even in bad snowpack years (like 1976-77), more could be retained in Powell because Mead had a buffer....which is gone today...
So the reality I think is that we're lucky Powell ever filled at all, and that right after it did, we were spoiled into thinking that would last forever by an unusually great span of heavy runoff years in the mid-1980s, the likes of which hadn't been seen before or since... compounded by the fact the lake had never experienced a drought of the magnitude that finally hit in 2000-04... and yet here it is today, holding its own, awaiting a probable giant runoff inflow in the next couple of months...
Just a very fascinating place, unique in the world, which tells its own stories, while keeping a few to itself...
The most interesting part though was at the end, when Chet Huntley laid out predictions of massive new urban areas that would result from the dam's presence, and that the lake would be filled in 5 years. Neither proved to be true (modern Vegas and Phoenix would have happened anyway without Glen Canyon Dam). It is true that the lake helped regulate flows into Lake Mead, which indirectly helped the reliability of the future Central Arizona's Project ability to provide water to Phoenix and that state in general... It also ironically helped the river rafting industry in the Grand Canyon, since the flows became more predictable and allowed for longer seasons... and of course certainly created a great recreation area... but not without some unforeseen environmental consequences, which in hindsight now seem obvious...
But the 5-year prediction to fill the lake was something I hadn't heard before. The reality was 17 years. Makes you wonder why they were so far off in that prediction. And yet it only took 7 years to fill it to a level we'd recognize today as "normal"--in 1970 it finally hit 3600... but from there it took another 10 years to fill the last 100 feet, and that only happened because of two massive years in the 1970s (1973 and '79) mixed in with a lot of up and down ones... The most crucial factor that allowed Powell to fill was that Lake Mead was about 100 feet higher than today, so even in bad snowpack years (like 1976-77), more could be retained in Powell because Mead had a buffer....which is gone today...
So the reality I think is that we're lucky Powell ever filled at all, and that right after it did, we were spoiled into thinking that would last forever by an unusually great span of heavy runoff years in the mid-1980s, the likes of which hadn't been seen before or since... compounded by the fact the lake had never experienced a drought of the magnitude that finally hit in 2000-04... and yet here it is today, holding its own, awaiting a probable giant runoff inflow in the next couple of months...
Just a very fascinating place, unique in the world, which tells its own stories, while keeping a few to itself...
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Dorado
Keeper of San Juan Secrets
Good comments JFR! I watched that Video a while ago and had similar reactions. I read somewhere that the extra time to fill was primarily from the increase in water development and usage upstream of Lake Powell that had occurred between the time Mead was filled and the construction of Glen Canyon Dam. But their estimated mean discharge for the Colorado has always been based off of tiny sample size (1905-1921) taken during an exceptionally wet period.....
Sedimentation loads and lifespan were also wildly optimistic, especially when you take into account how much more rapidly the sediment moves toward the dam when lake levels are low. Low lake levels and high runoff years really push the sediment plume downstream!
Sedimentation loads and lifespan were also wildly optimistic, especially when you take into account how much more rapidly the sediment moves toward the dam when lake levels are low. Low lake levels and high runoff years really push the sediment plume downstream!
powellobsessed
Active Member
I love these old documentaries! There’s another one on the dam construction it’s self I’ve seen before on YouTube it’s a good watch. It’s called operation glen canyon dam.
Dorado
Keeper of San Juan Secrets
For us of a certain age, they do feel pretty nostalgic. I kind expect a lot of popping and static...and the film to get stuck in the projecto like in school!!!
"Holding our own" is buffered by Lake Mead drawing down considerably more than ever before. Due in part if not mostly by the growth of Las Vegas (as maybe predicted in the film but delayed many decades from the original prediction), Lake Havasu and Laughlin grew, the western water pacts downstream have had a hand in using upper basin water too much for years. We've all seen how the discharge into the Upper Sea of Cortez has dwindled to nothing (maybe partially fixed by recent agreements to allow more flow there but still "usage" of the resource). I'm by no means an expert on water usage but it does seem to me that we have put a strain on the collection of water up stream for decades by our usage demands downstream.
Keeping "our" lake full will probably never be a reality as they will never again want to be in the situation they were in in 83/84 where we almost topped the dam with heavy flows from upstream. Did anyone catch the historic high flow rates of 190,000 cfm (or 1.5 million gallons per minute)? We're a buffer to take up the slack and store in good years and release in bad so we will always be down from full pool by design for "just in case" wet year events.
I lived in Las Vegas for over a decade and always wondered about green lawns in the desert? Seemed incongruent to me. Lush green golf courses everywhere where only rocks and Gila Monsters naturally grew. Everything downstream of us here has had an affect on how much we can retain in the lake let alone the drought we have been under for years. Its like taxes and spending- until we get spending under control (usage of the water) we'll never get taxes (deficit) to lower (money in the bank), no matter how much water we gather. What we gather in good years will only last so long until the next drought. And there will be another "wet years" event and more dry years events. Just look to what we now call "the Ancient Ones" or Anisazi. They were here for hundreds of years and died out from what we can tell (by some guesses) because of drought. Look to the vast beds of 64 million year old oysters out on the Cottonwood Canyon Road. We were under water then but we're a desert now. It will all change with time- lots of time, over millennia and we have no or very little affect on that outcome. But we can change how we use the resources we now have. The water we have now will run out at some time- then what? The population down stream will have a problem to solve.
The baseline estimate from the turn of the last century (1905-1921) I find very amusing. Take a small, short sampling period of "weather" and extrapolate it into a century or more estimate as a basis for the postulation of the end point. Obviously "we" were way off there in in-flow quantity over the long term because of the maybe "cherry picked" short sample period (I'm sure usage was like wise under estimated by design and/or actual, unpredictable reality). Where else can we see the same "estimate/outcome" predictions in today's life? A very minuscule sample period (compared to the known previous lifespan) to predict a sudden short period outcome (again compared to the available lifespan data)? If we were so far off here with this lake and water usage over the prediction (only 50-60 years), how can we possibly be any more accurate with current predictions of other even more massive in size events to come? Just thinking out loud. Things can be "cherry picked" for an outcome either way.
It was once said that there is no world wide water shortage- Only a distribution problem.
For me the take away was the engineering involved and the logistics to get the job done. Its amazing what we can accomplish when pushed to an end point.
Keeping the concrete cool till poured was something I had never heard of or thought of. Of course, it took decades for it to cool down after pouring as concrete warms as it hardens. That I knew.
Keeping "our" lake full will probably never be a reality as they will never again want to be in the situation they were in in 83/84 where we almost topped the dam with heavy flows from upstream. Did anyone catch the historic high flow rates of 190,000 cfm (or 1.5 million gallons per minute)? We're a buffer to take up the slack and store in good years and release in bad so we will always be down from full pool by design for "just in case" wet year events.
I lived in Las Vegas for over a decade and always wondered about green lawns in the desert? Seemed incongruent to me. Lush green golf courses everywhere where only rocks and Gila Monsters naturally grew. Everything downstream of us here has had an affect on how much we can retain in the lake let alone the drought we have been under for years. Its like taxes and spending- until we get spending under control (usage of the water) we'll never get taxes (deficit) to lower (money in the bank), no matter how much water we gather. What we gather in good years will only last so long until the next drought. And there will be another "wet years" event and more dry years events. Just look to what we now call "the Ancient Ones" or Anisazi. They were here for hundreds of years and died out from what we can tell (by some guesses) because of drought. Look to the vast beds of 64 million year old oysters out on the Cottonwood Canyon Road. We were under water then but we're a desert now. It will all change with time- lots of time, over millennia and we have no or very little affect on that outcome. But we can change how we use the resources we now have. The water we have now will run out at some time- then what? The population down stream will have a problem to solve.
The baseline estimate from the turn of the last century (1905-1921) I find very amusing. Take a small, short sampling period of "weather" and extrapolate it into a century or more estimate as a basis for the postulation of the end point. Obviously "we" were way off there in in-flow quantity over the long term because of the maybe "cherry picked" short sample period (I'm sure usage was like wise under estimated by design and/or actual, unpredictable reality). Where else can we see the same "estimate/outcome" predictions in today's life? A very minuscule sample period (compared to the known previous lifespan) to predict a sudden short period outcome (again compared to the available lifespan data)? If we were so far off here with this lake and water usage over the prediction (only 50-60 years), how can we possibly be any more accurate with current predictions of other even more massive in size events to come? Just thinking out loud. Things can be "cherry picked" for an outcome either way.
It was once said that there is no world wide water shortage- Only a distribution problem.
For me the take away was the engineering involved and the logistics to get the job done. Its amazing what we can accomplish when pushed to an end point.
Keeping the concrete cool till poured was something I had never heard of or thought of. Of course, it took decades for it to cool down after pouring as concrete warms as it hardens. That I knew.
Trix
Keeper of San Juan Secrets
This thread is evolving from Recreation to Issues, but so be it. We all seem to long for a full lake, but my casual observation is that most reservoirs are not operated to fill to the top of the dam every water year. California lakes have a "full pool" level. I don't know how that is established, but most of the CA lakes are now above full pool. I don't think it's a "fair" depiction to commonly state that Powell and Mead are about 38% full. Factually correct but percent of historic average for the current date might be a better metric. Too lazy to go to LPWDB to find or calculate today's average, but guessing we are, say, 55% of average. Not good, but better than 38%.
Anyway, love to again see the history of the construction and no one could ever convince me that it hasn't been a tremendous investment benefiting millions of water users and recreationalists. Only perhaps a few thousand young, wealthy folks would have explored the majesty of Glen Canyon but for Lake Powell. We millions call it our boating paradise.
Anyway, love to again see the history of the construction and no one could ever convince me that it hasn't been a tremendous investment benefiting millions of water users and recreationalists. Only perhaps a few thousand young, wealthy folks would have explored the majesty of Glen Canyon but for Lake Powell. We millions call it our boating paradise.
Dorado
Keeper of San Juan Secrets
The lake has certainly fulfilled its purpose, to mitigate against drought and increase storage. Recreation was always a secondary benefit, and has been a huge boon and bonus to the local economy.
I think the big difference between LP and most reservoirs is the tremendous capacity compared to the relatively small discharge of the Colorado. The reservoirs in California and Washington state, are not as big, but many of the rivers feeding them are (much) larger. Even in extreme drought, they can recover with one wet year. Powell and Mead are so huge, they are going to need a bunch of wet years in a row....or descrease consumption.
To me, the really surprising thing is how much of what we collectively think of as a "terrible drought" over past 20 years was really not that much below the long term average. Water delivery to lake mead has been over the 7.5 million acre feet...but it keeps dropping...
I think the big difference between LP and most reservoirs is the tremendous capacity compared to the relatively small discharge of the Colorado. The reservoirs in California and Washington state, are not as big, but many of the rivers feeding them are (much) larger. Even in extreme drought, they can recover with one wet year. Powell and Mead are so huge, they are going to need a bunch of wet years in a row....or descrease consumption.
To me, the really surprising thing is how much of what we collectively think of as a "terrible drought" over past 20 years was really not that much below the long term average. Water delivery to lake mead has been over the 7.5 million acre feet...but it keeps dropping...
That was a good film and different than others I've seen. Thanks for posting.
I wonder how we would build the dam today differently, from an engineering and construction perspective? I wonder how technology has improved/changed? Would it be much easier to build today? Could it be built quicker? Would it be as thick? If any of you have any expert incite on this question I'd be interested in hearing your thoughts.
I wonder how we would build the dam today differently, from an engineering and construction perspective? I wonder how technology has improved/changed? Would it be much easier to build today? Could it be built quicker? Would it be as thick? If any of you have any expert incite on this question I'd be interested in hearing your thoughts.
JFRCalifornia
Keeper of San Juan Secrets
I think it would be impossible to build the dam today. Obviously it could be designed, no doubt even better than in the late 50s/early 60s from an engineering standpoint, but certainly not built any quicker than in the 1950s/60s, and for reasons that have nothing to do with engineering. For starters, the cost alone (and source of funding) would be a huge stumbling block... but the real project killer would be an infinitely more robust public outreach process than was ever contemplated (or possible) in the 1950s, combined with the environmental laws that are on the books now, particularly NEPA (enacted 1969), which was really a direct response to Glen Canyon Dam being built and the two dams in Grand Canyon that were never built in the 1960s.
In considering a possible design for a dam today, here's the first question that would arise: Is the dam the best (and most feasible) solution to the basic goals it's trying to accomplish? That would trigger a healthy (and lengthy and heated) discussion that leads to all kinds of possible solutions never considered or even dreamed of at the time Glen Canyon Dam was designed and planned. I have no idea what the best answer would be, but to answer your direct question, the ultimate project that achieves those goals would likely look considerably different today, based in part on modern engineering and construction considerations. My guess is that it would be a much smaller project, not nearly as grand in scale or as elegant in design. Functional. A series of compromises, which may or may not serve the project (and the public) for the better.
Giant public works projects like the huge western dams, the Interstate highway system, massive bridges and tunnels could only have come about with the perfect conditions, which really existed only from about the 1920s through the mid-1960s. You had the technology, the political will, the almost unquestioned dogma that Big Projects = Progress, funding priorities, cheaper labor, the dynamics of the Great Depression, and--just as importantly--lack of public information or awareness of many of the places where such projects would be built, the ability to suppress or ignore important stakeholders affected by such decisions, and complete absence of environmental laws. In a sense, it was like the height of the Roman Empire, which is probably viewed nostalgically by many as "the good old days", but in fact, as with many things, that's only from a certain narrow perspective. The reality is that massive public works projects are (and always have been) much easier to build when there's an authoritarian push behind them, for better or worse. In the case of Glen Canyon Dam, this push gave rise not only to a drastically changed physical environment in the Colorado River basin, but also a completely new economic and political landscape, and (like it or not) literally galvanized the framework of environmental laws we have today, both federally, and especially in states like CA.
Hard to overstate the changes that came about as a result of the dam. And if the project were considered from scratch today, there would never be enough agreement on its design, location, purpose, likely consequences, perceived benefits, and economics for it to ever get off the ground. Just my guess of course, but it's based in part on my own experience working on the planning and environmental end of major water-related public works projects in CA, where it takes 10 years or more (literally) to study, plan, design, fund and build even a simple wastewater treatment plant that recycles water for a small town, nothing on the scale of a great dam like Glen Canyon, Hoover, Shasta or Oroville. That's not a criticism, just democracy in action. Democracy is messy. But so is peanut butter, and both are good things.
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linnell
Well-Known Member
Where does the money trail lead? That could be where your answer is.
NUC- Coast Guard talk for "Not Under Control" or drifting - Kinda like where this thread is going.
Back under control. For its time, it was an engineering marvel, situated in the middle of no where, where even the most basic of services had to be brought in. It was designed with slip sticks (if anyone remembers what those were) and in some instances dug by hand. They did it without air conditioning. They hung on those walls or worked in the bottom of the canyon in 100 degree heat in the summer and froze in the winter. They lived in trailers and the Windy was not there then. OSHA was no where in sight then (as evidenced by riding the cable trolley by climbing on).
I don't think it could be built today, just because of the OSHA requirements, it would double in build time making it way too costly. None of them envisioned the amount of recreation this lake would bring to millions of people back then. We're looking at 3 million visitors passing through here in the next year or so! 3 MILLION! Horseshoe Bend is already outdated and its not even finished yet.
Back under control. For its time, it was an engineering marvel, situated in the middle of no where, where even the most basic of services had to be brought in. It was designed with slip sticks (if anyone remembers what those were) and in some instances dug by hand. They did it without air conditioning. They hung on those walls or worked in the bottom of the canyon in 100 degree heat in the summer and froze in the winter. They lived in trailers and the Windy was not there then. OSHA was no where in sight then (as evidenced by riding the cable trolley by climbing on).
I don't think it could be built today, just because of the OSHA requirements, it would double in build time making it way too costly. None of them envisioned the amount of recreation this lake would bring to millions of people back then. We're looking at 3 million visitors passing through here in the next year or so! 3 MILLION! Horseshoe Bend is already outdated and its not even finished yet.
Great questions, Peg! Would be fascinating to see answers to these questions...
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