
Vast Freshwater Reserves Found Beneath the Oceans - mankypro
http://www.sciencedaily.com/releases/2013/12/131208085304.htm
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ryan_j_naughton
Regarding criticism that this isn't renewable and delays the move to renewable
resources:

At the rate we are damming rivers, we will destroy many river ecosystems. This
new potable water source seems less harmful than dams and could be a bridge
until the energy costs of desalination are low enough.

If this discovery spurs investment in desalination (since this is simply
cheaper desalination due to the lower salinity) that would be an added benefit
as it would accelerate the move toward desalination.

Perhaps we could skip the dams entirely (which though seemingly renewable from
a water perspective, are highly destructive to river ecosystems).

~~~
schiffern
>until the energy costs of desalination are low enough.

Really? You think desalination is the ultimate goal? I much prefer free,
ecosystem-provided desalination (aka rooftop rain-water harvesting).

As for agricultural water use, I highly suggest picking up a copy of P.A.
Yeoman's classic _Water For Every Farm_. It details how proper runoff
management, evaporation control, and correctly-scaled earthworks can provide
reliable water availability with near-zero energy inputs [other than the sun,
of course].

As for dams, it's not as simple as "all dams are bad". Oversized dams that are
out of scale with the local hydrology are the problem.

But, I guess some people would prefer to re-invent the Earth's water cycle!

~~~
ryan_j_naughton
I agree that not all dams are bad. The real issue with dams is the scale. We
are on track to dam the majority of the world's rivers over the next 50 years,
and this will have significant effects on river and coastal ecosystems.

>> I much prefer free, ecosystem-provided desalination (aka rooftop rain-water
harvesting).

I agree; however, this is not an infinite supply. Taking water from rivers is
effectively a form of this and it is lower cost than many other "free,
ecosystem-provided desalination" since the water has already been collected
into a river due to gravity and land contours. As we remove water from these
'free' sources, we are depriving an ecosystem of that water.

The worst case scenario is something like the Aral Sea
[http://en.wikipedia.org/wiki/Aral_Sea](http://en.wikipedia.org/wiki/Aral_Sea)

~~~
schiffern
>The real issue with dams is the scale.

I couldn't agree more.

>I agree; however, this is not an infinite supply.

Well no system can provide an _infinite_ supply, but rainwater harvesting
could support the current human population at a first-world standard of living
(something our present system does not provide). Many areas famous for recent
crippling droughts suffered from _flooding_ only months before. This is a
spectacular failure in water management.

As to cost, I haven't seen any comparisons of the lifetime cost of rooftop
rainwater harvesting vs centralized pumped underground pipe distribution. I
know rainwater harvesting is much more common in Australia, so they might have
more data. I suspect it's strongly dependent on the cost of energy.

One thing I forgot to mention about desalination: current technology
(specifically the Affordable Desalination Collaboration’s pilot plant) is at
30% of the thermodynamic limit. So we can expect a 3x improvement in
performance, but no more.
[http://www.usbr.gov/research/AWT/energy_use.html](http://www.usbr.gov/research/AWT/energy_use.html)

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devindotcom
Good, now we can put off thinking about conservation yet again! Our great-
grandchildren will have plenty of time to think of something.

~~~
astrodust
Carbon credits today, water credits tomorrow.

~~~
kamjam
Soon to be followed by shale fracking for water.

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clord
We're contemplating going after harder-to-get fossil water because the easy
stuff is depleted and can no longer keep up. Sounds like the situation we're
in with oil.

In the case of water, which replenishes, the 'production cycle' is actually
the global fresh-water cycle. If we dirty all of the fresh water faster than
the earth can clean it, we're going to have to start drilling for the fossil
stuff in hard-to-reach places. It's strange to think there would be drilling
rigs in the ocean with people risking their lives and taking danger pay... for
water. It raises a question in my mind: affordability. Who is going to be able
to afford to buy all their water like this?

It's the next step now that there are several major rivers no longer reaching
the ocean.

~~~
eru
> Who is going to be able to afford to buy all their water like this?

The price of water can never really climb above the price of desalination.

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leeoniya
hmmm, the ocean's pretty heavy. i wonder what extracting an incompressible
fluid from the seafloor's support structure will do to weaken it. will they
fill it with saltwater instead?

i guess it shouldnt be much different than oil drilling :\

~~~
Danieru
This might be off-topic but water is in-fact compressible:
[http://en.wikipedia.org/wiki/Properties_of_water#Compressibi...](http://en.wikipedia.org/wiki/Properties_of_water#Compressibility)

~~~
jbattle
Getting further afield, water's density actually changes considerably with a
change in temperature.
[http://en.wikipedia.org/wiki/Properties_of_water#Density_of_...](http://en.wikipedia.org/wiki/Properties_of_water#Density_of_water_and_ice)

I'm not sure how common this is but I know Lake Michigan goes through an
annual cycle where the water alternately mixes and segregates (by
temperature). In the summer, the warm, less dense water rises to the top and
stays there. In the winter, very cold water is actually lighter than slightly
warmer water and a similar stratification happens. In spring and autumn the
water temperatures near the surface equalize with water deeper in the lake and
much if not all of the lake water circulates ("turns over").

[http://www.lakeaccess.org/ecology/lakeecologyprim4.html](http://www.lakeaccess.org/ecology/lakeecologyprim4.html)

~~~
b_emery
Very common - this is one of the basic mechanisms that mix lakes. To clarify,
the summer surface waters are heated by the sun, causing stratification. This
is usually broken down in the fall by the combination of wind mixing and heat
extraction (leading to denser surface waters which sink). This is an important
component of ocean surface dynamics as well. The mechanism just described can
mix the top few hundred meters of the North Atlantic in winter.

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TrainedMonkey
Newsflash - vast freshwater resources had been found sitting in form of ice on
planetary caps. Those vast supplies of water are expected to last till 2030.

On a serious note, this could be big. Imagine oil like drilling platforms that
pump water instead. Now we only need to figure out how economical this is.

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sanskritabelt
I guess there really is water at the bottom of the ocean.

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bigtech
Once in a lifetime, water flowing underground.

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ironmanjakarta
Govt is the cause of water shortages

[http://www.lewrockwell.com/2013/10/ryan-mcmaken/socialist-
wa...](http://www.lewrockwell.com/2013/10/ryan-mcmaken/socialist-water-
troubles/)

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programminggeek
Well, this is about the time we see crazy theories about some crazy
civilizations living inside the planet with all this fresh water and heat
freely available to them....

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ryanjodonnell
Getting the water out of reserves beneath the ocean sounds expensive - I
wonder how it stacks up energy wise vs desalination of ocean water.

