[HN Gopher] What happens when a reservoir goes dry
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What happens when a reservoir goes dry
Author : chmaynard
Score : 119 points
Date : 2022-07-19 19:10 UTC (3 hours ago)
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| afc wrote:
| > But, I'm explaining all this to clarify one salient point: an
| empty reservoir isn't necessarily a bad thing.
|
| Well, yeah, just like an empty battery isn't necessarily a bad
| thing; it means it has been used, which is probably better than
| having prevented it from being used, but ... still worrying, in
| the sense of having ran out of storage/capacity. Not very
| convinced of this point.
| woutersf wrote:
| Roman aquaducts come to mind
| Scoundreller wrote:
| Paris still gets about 15% of its water through an "aqueduct"
| 100km away:
|
| https://fr.m.wikipedia.org/wiki/Aqueduc_de_l%27Avre
|
| (Can't find an English copy so you'll have to machine
| translate)
| namecheapTA wrote:
| For a lot of people that live in waterless areas, I have a
| feeling they also drive a lot. I personally use several gallons
| of gasoline a day. Think of how hard that gasoline is to get to
| me. It would be trivial to get me a 2 gallons of water a day to
| live no matter how large the desert I live in is.
|
| As long as food production is taken care of where water is,
| getting people drinking water is pretty easy.
| rootusrootus wrote:
| Would you like to pay $4.50 per gallon of water?
| elmer007 wrote:
| This is the first time I've seen his blog, but I've been watching
| his videos on YouTube for a while.
|
| My brain read the entire post in his voice, and I couldn't seem
| to turn it off. What's interesting is that I felt like I
| understood the post better, and I think it may be that I was
| reading it slower, as if he were speaking it. He has a really
| pleasant way of explaining things.
| [deleted]
| PopAlongKid wrote:
| TL;DR when a reservoir goes dry, people pay more to get water
| from other sources.
|
| "We don't so much run out as we just use more expensive ways to
| get it. "
| eloff wrote:
| And subsidized or unsustainable usage like agriculture or lawns
| may cease to make sense and go away.
| falcrist wrote:
| This applies to most natural resources including gas and oil.
|
| There's never going to be a moment when we squeeze the last
| drop of oil out of the Earth's crust. It's just going to keep
| getting more expensive as we drain the easier sources and have
| to look harder and drill deeper in more and more remote areas.
| latchkey wrote:
| I just did a two week long back country road campervan trip from
| Tahoe down south through each of the forests... Stanislaus,
| Yosemite, Sierra, Kings, Sequoia. It was amazing boondocking in
| the middle of nowhere, no cell signal and taking baths in what is
| left of the rivers and lakes...
|
| Once you get past Yosemite, pretty much all of the reservoirs are
| empty to less than half full. Majority of the streams are gone.
|
| It gets worse the further you head south. Kings and Sequoia are
| pretty much decimated forests from the fires and beetles. Dead
| trees for as far as you can see. Given the lack of water, I
| expect them to be desert in just a few more years.
|
| There are quite a few hydro power generation stations deep in the
| mountains that I had no idea existed. I suspect they will close
| down as well. I wonder what effect that will have on California
| power supply over the coming years. That said, it was pretty
| clear that PG&E is working on updating the infrastructure as they
| are all over the place working on things.
|
| If I hadn't seen it for myself, I wouldn't believe it. The extent
| of damage is pretty massive and it would take quite a lot of rain
| to 'fix' things. So much so that it would probably end up just
| flooding everything, creating just as much of a mess.
| DoneWithAllThat wrote:
| This is straight up hyperbole. No, those areas are not going to
| deserts in the next few years, or even our lifetimes.
| latchkey wrote:
| I'm not saying all of the areas I went through are going to
| desert... but if you look at the extent of the damaged areas,
| I doubt that you're going to see the same forests come back
| again in our lifetimes. Take a look at the Pine Ridge area.
| As far as the eye can see, everything is gone. Driving
| through Sequoia, huge swaths of the trees are gone. It is
| 100+ degrees in the summers and no water...
| spike021 wrote:
| I have no context on this kind of thing, but we have oil
| pipelines, is there a reason we can't use water pipelines from
| areas with drastically more rainfall and just transport said
| water to scarcer areas?
| [deleted]
| klodolph wrote:
| We already do this. Consider Las Vegas... its water comes from
| the Colorado River. (Edit: to be clear, the Colorado River
| itself is transporting water from areas with high rainfall to
| areas with low rainfall. The Las Vegas area is a desert, but
| most of the Colorado River basin is not.)
|
| It's just not generally done over long distances. Oil is pumped
| over long distances, but it's also much more valuable. For
| water, we rely more on cheaper ways of transporting it, and
| transporting it over shorter distances, using things like
| aqueducts and, yes, pipelines.
|
| Here's an example of a big water pipeline project:
|
| https://en.wikipedia.org/wiki/Northern_Cyprus_Water_Supply_P...
| MooMooMilkParty wrote:
| Just adding to this, not far south of Las Vegas the Central
| Arizona Project is a rather large canal (so not exactly a
| pipeline but close enough) which transports Colorado River
| water to Phoenix and Tucson.
|
| https://en.wikipedia.org/wiki/Central_Arizona_Project
| khuey wrote:
| We do this in some cases, but in general oil is expensive and
| water is cheap. A gallon of crude oil costs around $2.50. A
| gallon of tap water costs a little over a penny where I live
| (in San Francisco). Transporting expensive things is an easier
| sell than transporting cheap things.
| pilom wrote:
| We already do this. In Colorado there are over 50 "Transbasin
| Diversions" that move water from one river basin to another.
| Most of them transfer water out of the Colorado River Basin to
| the east side of the continental divide, usually the Arkansas
| River or South Platte River Basins. California also does this
| on a vast scale to move water from the wetter north to the
| drier south parts of that state.
|
| There are many issues with transporting large quantities of
| water vast distances. From legal (it is illegal to transport
| water from the Great Lakes to outside of their basin), to
| physics (water is expensive to pump up and over mountain ranges
| and building tunnels is incredibly expensive.
|
| Basically, just like there are only so many places that it is
| cost effective to build dams or pumped hydro electricity
| storage, there are only so many places that it is cost
| effective to build pipelines.
| la64710 wrote:
| So what next? It is amazing how little resources we are devoting
| to solve the existential problem of water scarcity that is even
| now happening almost everywhere around the world. Maybe we won't
| realize until it suddenly hit us? I hope I am wrong.
| pilom wrote:
| "Buy and dry" is the default outcome. Cities buy the farms
| nearby, use the farms' water rights and let the fields go dry.
| Agriculture uses 60-90% of the water in the west depending on
| river basin. Cities can afford MUCH higher rates per gallon for
| water than farmers can so the cities will eventually just buy
| out the farmers if nothing changes. I have no worries about
| Denver or Las Vegas or LA running out of water. There just
| might not be water intensive crops grown out west anymore.
| [deleted]
| RcouF1uZ4gsC wrote:
| > the existential problem of water scarcity
|
| Basically, everything is an energy problem. If we have cheap,
| clean, energy, we can solve a lot of our problems.
|
| For example, if we had nuclear powered desalination plants, we
| could have more than enough fresh water.
| nicoburns wrote:
| > Basically, everything is an energy problem
|
| Yes, and in the vast majority of cases the easiest way to
| solve an energy problem is to use less energy rather than
| produce more. This applies to water (where it's much easier
| to use it where it naturally rains), transportation,
| heating/cooling, etc, etc.
| bell-cot wrote:
| Except that, in today's world, everything is basically a
| NIMBY problem...
| nerdponx wrote:
| Humanity will ignore its existential problems until existence
| becomes immediately threatened.
| tejohnso wrote:
| Unfortunately humanity as a whole isn't immediately
| threatened until smaller pockets have already lost habitat.
|
| And by the time all of humanity is immediately threatened
| it's too late to save it.
| trophycase wrote:
| It's not an existential problem so much as a political problem.
| We can literally always boil water. The planet is 70% water and
| it's not going anywhere or getting converted into other things.
| paulryanrogers wrote:
| Boiling requires energy and doesn't remove the salt. Cleaning
| polluted water can be even more energy intensive. So it is
| getting converted from fresh water into polluted water, all
| the time.
| wvenable wrote:
| We're paralyzed by the fear of doing something. What if we do
| something unnecessary? What if we do something but it makes
| things worse? What if do something but it costs too much?
|
| I'm almost positive we (humans) won't do anything until there
| is absolutely no other choice but to do something.
| snoopy_telex wrote:
| Americans^wHumans can always be counted on to do the right
| thing...after they have exhausted all other possibilities.
| lurquer wrote:
| Who is this 'We' of whom you speak?
|
| While 'you' may not be devoting time and money towards this
| problem, rest assured that 'They' are.
|
| There is plenty of water. The methods of distributing it vary
| across the decades and centuries. But, it gets done. By people
| 'we' hire through 'our' taxes and water bills to do it.
|
| At any given time, there are reservoirs being planned, water
| rights being negotiated, drills being sunk, pipelines being
| laid, etc. It gets done. It always gets done. If people wish to
| live in a desert, they'll get water one way or the other. If it
| gets too expensive, they'll move. No big deal.
| Overtonwindow wrote:
| "Engineers and planners don't actually know what the worst case
| scenario drought will be over the lifetime of a reservoir."
| anigbrowl wrote:
| We're well on our way to finding out. One of the transformers
| on the Hoover Dam blew up this morning; no interruption to
| water or electrical output, but a troubling reminder of the
| possibilities.
| Victerius wrote:
| Hmmm, total depletion, Aral Sea style? Why isn't that the worst
| case scenario?
| pitaj wrote:
| I think you misunderstood.
|
| That quote is saying that planners have no way of actually
| predicting how bad the worst possible drought will be for the
| area serviced by the reservoir over the lifetime of the
| reservoir, so they can't actually design the reservoir to
| handle the worst-case scenario.
| ziddoap wrote:
| Worst-case _drought_ , as in, for how long. Not the worst-
| case scenario for the reservoir.
|
| If they knew the worst-case drought possible would last N
| days, they could design the reservoir to hold N+1 days worth
| of water. Alas, they don't know N.
|
| Edit: Near end of day... Can you tell? Wrote draught instead
| of drought.
| Terr_ wrote:
| > Near end of day... Can you tell? Wrote draught instead of
| drought.
|
| Just before your edit, I spent a while amused at the vision
| of some guy trying to chug the entire reservoir while being
| egged-on by inebriated friends.
| bombcar wrote:
| Why didn't they build it with 3001 hulls!
| MegaButts wrote:
| What a wonderful reference.
|
| https://youtu.be/xJxwvZ5SE_c
| airza wrote:
| >Eventually, irrigated farming in Arizona and Nevada may become a
| thing of the past.
|
| Why is there irrigated farming in Arizona?? It's a desert!
| HWR_14 wrote:
| Because too many water rights were assigned 100 years ago, and
| if the farmers stop using it, they'll lose the water rights. So
| they grow alfalfa in the desert to use up the water so they can
| keep the water rights.
| capableweb wrote:
| I'm guessing this is the source for that:
| https://youtu.be/jtxew5XUVbQ?t=512
| HWR_14 wrote:
| I mean, that is a source, but it was pretty well reported
| before that.
|
| Although I thought they assigned too many water rights
| because they measured in a period of flooding. John Oliver
| is the first time I heard that they knew it was a lie at
| the time.
| apcragg wrote:
| Marc Reisner's book Cadillac Desert talked about this as
| far back as 1986.
| imoverclocked wrote:
| Their soil is extremely fertile. You can grow just about
| anything, even cotton, given enough water.
|
| Edit: grammar
| mikewave wrote:
| Sounds like they should just start digging up and selling the
| soil, no?
| moralestapia wrote:
| If you didn't meant this as sarcasm, this is pretty much
| the worse thing you could do.
| mikewave wrote:
| I'm no farmer, but I'm all ears! If you have dry useless
| soil and can't water it, does it not have some residual
| value as an export product?
|
| I suppose this is assuming that there's not going to be
| water in the future, and that you just want to extract
| whatever use there is left from an area before giving it
| over to desertification.
| moralestapia wrote:
| Soil, and topsoil in particular, is an extremely valuable
| and non-renewable resource. When land becomes barren it
| could take 100s of years to regenerate, or it may never
| do, as in this case this is a desert and for this process
| to happen you need a continuous stream of biomass and
| microbes doing their stuff.
|
| If they did this, in a couple years they still wouldn't
| have water, and now they'd also wouldn't have land to
| pour the water onto, so they will end up in an ever worse
| state than now.
| stewarts wrote:
| While not worthless, as there would still be nutrients
| present. A good bit of soil quality comes from the
| microorganisms within it.
| lovich wrote:
| Soil is a complex ecosystem, digging into it, or worse
| excavating it, removes a lot of the value
| lesuorac wrote:
| I suspect at some point it'd make more sense to pump (hopefully
| via gravity) water to a location and farm then it would to
| transport food.
| [deleted]
| irrational wrote:
| Why is there a large city (las Vegas) in the middle of a
| desert?
| cardiffspaceman wrote:
| Because there was a little town in the middle of the desert,
| and it got popular.
| TylerE wrote:
| This is a fairly recently development too.. in 1940 it had
| a population of only 8000.
| crikeyjoe wrote:
| pitched wrote:
| Reminds me of the engineering twist on "glass half full" as
| "glass is twice as large as it needs to be". Here's hoping it
| wasn't built too small though.
| conductr wrote:
| > Why build it so big if you're not going to use the stored water
| during periods of drought? Storage is the whole point of the
| thing... except there's one more thing to discuss: Engineers and
| planners don't actually know what the worst case scenario drought
| will be over the lifetime of a reservoir.
|
| In regards to Lake Mead, perhaps others, the size and keeping it
| near full affords you time to find an alternative supply or some
| other solution that is undeterminable at concept/construction.
| TylerE wrote:
| That time is gone though... Lake Mead was last full in 1983,
| and has been steadily declining since... it's now at about a
| quarter of peak capacity.
| conductr wrote:
| I don't think the original engineer's would have anticipated
| the level of inaction that's occurred. Same goes for ability
| to build/delays/regulation
| bee_rider wrote:
| "Let's use the safety buffers provided by the original
| designers to ignore the problem as long as we can" has been
| our national infrastructure plan so far this century.
| rootusrootus wrote:
| Too busy arguing about abortion and what bathroom someone
| is allowed to use, whether someone is racist or
| communist, and if it's even possible for the government
| to do useful things or if private enterprise should run
| society.
|
| I don't see that changing anytime soon. We'll just look
| the other way while infrastructure crumbles around us,
| and then point fingers blaming each other for failing to
| notice.
| labrador wrote:
| Someone important to me, who I love but watches a lot of Fox News
| always gives me the party line on this issue.
|
| According to them, it's the fault of little fish we are trying to
| keep from going extinct by supplying it with precious freshwater.
| This is after far left environmentalists took over the Democrat
| party. Oh, and climate change is a hoax. This is just a normal
| drought.
|
| I think it's actually a failure of political leadership. I'm not
| saying it's easy to get multiple states to respond to a crisis,
| but as long as it doesn't happen people continue to use water as
| they did before.
| jameshart wrote:
| If you're the kind of person who learned orbital mechanismcs
| through Kerbal Space Program and deepened you understanding of
| backpressure and supply chains with Factorio, and you are looking
| for a similar way to get a deeper feel for water resource
| management, can I suggest taking a look at Timberborn, the post-
| apocalyptic beaver simulator. You have to figure out how to
| engineer a reliable water supply in the face of epic dry season
| droughts.
| jfim wrote:
| How playable is it? It seems that there are many complaints
| about the district system and the beaver AI being not so
| bright.
| jameshart wrote:
| All part of what makes it an accurate simulation of
| Californian water management.
| photochemsyn wrote:
| The wild political madness involved in the grand project to water
| the American West is detailed in Marc Reisner's "Cadillac Desert"
| (1986), and is a must-read for anyone wanting to understand the
| current situation. It was written before a climate-related
| megadrought was really on anyone's long-term radar, but it really
| explains a lot.
|
| For example, dams are only part of the water storage picture,
| there's also groundwater, and the water projects often had the
| goal of protecting groundwater (keeping the water table closer to
| the surface), but then once they'd provided water via a dam or
| aquaduct, the farmers would just expand the areas they were
| farming and groundwater extraction would often increase as a side
| effect.
|
| Humans really aren't that good at long-term planning, is one
| conclusion.
| MooMooMilkParty wrote:
| Also worth reading, and considerably more up to date, is
| Science Be Dammed.
|
| https://uapress.arizona.edu/book/science-be-dammed
| atoav wrote:
| > Humans really aren't that good at long-term planning, is one
| conclusion.
|
| Especially not within a system that gives you cool prizes if
| you don't.
| knodi123 wrote:
| In the science fiction novel "The Water Knife" by Paolo
| Bacigalupi, characters are always name dropping "Cadillac
| Desert" and talking about how prophetic and what a must-read it
| is.
|
| Just as an aside.
| ianai wrote:
| And this is a pretty funny/wild take on how water rights can
| play out in the US Southwest (Milagro beanfield war). All too
| true to life.
|
| https://en.m.wikipedia.org/wiki/The_Milagro_Beanfield_War_(n...
| dqh wrote:
| > Humans really aren't that good at long-term planning, is one
| conclusion.
|
| I think the problem is long-term co-operation rather than
| planning. The temptation of short-term gain is always too great
| for someone.
| colinmhayes wrote:
| Humans are actually pretty good at long term planning. What
| we're not good at is solving externalities. The problem with
| water usage is that we haven't created a system that aligns
| incentives with our goals. Why would any farmer conserve water
| when they think the farm next door isn't? Since water is a
| shared resource if you don't use it someone else will.
| rootusrootus wrote:
| Yeah we need to ditch the legacy water allocation methods and
| meter everyone. Then we can just jack up the price as
| necessary.
| micromacrofoot wrote:
| It's fun to imagine an alternate species that can plan
| practically for the future. Even a simple rule or two... like
| "don't put cities in inhospitable places" would be
| transformative. We've got plenty of room in places that aren't
| completely barren and devoid of water, though these pesky (and
| mostly imaginary) borders often manage to get in the way.
| irrational wrote:
| I live in an area that gets a lot of rain during 9 months of the
| year (and this past spring was the wettest spring in memory - it
| just wouldn't stop raining hard. The local rivers even reached
| low flood stage.) So, my initial thought is our rates probably
| won't go up. So we are fine. But reading this article I realized
| that what will go up is food prices. The prices have already gone
| up, but will probably go up a lot more.
| lloydatkinson wrote:
| Really enjoy his posts and videos. I'm waiting for his book to be
| released.
| capableweb wrote:
| Grady have been doing a great job since day 0 with his videos,
| I'm so glad to see him working on publishing a book now, and
| that the quality of the videos are getting better and better
| too!
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