Depletion Comes Knocking As Parts Of The Ogalalla Begin To Fail

[hatrack]

EDIT

"An estimated 5 billion gallons is pumped from the Ogallala aquifer annually with the majority of it going to irrigate farm fields in South Dakota, Nebraska, Kansas, Colorado, Oklahoma, Texas, New Mexico and Wyoming. Farmers tap into the Ogallala to help them grow corn, cotton, wheat, soybeans and other crops, which become food products or fatten livestock.

Estimates of the aquifer's long-term sustainability vary according to geography, with some areas of the underground water supply still showing another 250 years of capacity or more. But many areas spread through the different states have far less time - maybe 60 more years of capacity, some experts say.

The depth of the aquifer varies from 150 feet in some areas to 750 feet or more in others. Some of the most critical areas are seeing the aquifer drop 3 to 5 feet a year, according to David Pope, chief engineer for the water resources division of the Kansas Agriculture Department.

"There are some areas where the amount of depletion is very significant," Pope said. "Those are areas that are having to make tough decisions about how to proceed."

EDIT

Longtime Kansas farmer Jerry Stuckey said the situation is becoming so serious where he farms in southwest Kansas that some farmers might embrace assistance for giving up irrigation. Stuckey has already started growing cotton in place of corn on 1,100 acres because cotton requires less water. "The wells around here are declining fast," Stuckey said. "Farmers are constantly trying to save all the moisture we can save. You have to survive."

EDIT/END

http://www.planetark.com/dailynewsstory.cfm/newsid/22975/story.htm

[Sliverofhope]

1. Makes one wonder

Plan B, a new book out about this... and peak oil... we're all going to be so screwed if this all turns out accurate.

[punpirate]

2. The Ogallala...

... in part because of its size, recharges at a rate of about one inch per year, and for many decades, the amount of water drawn from it exceeds by several times the recharge rate.

It is true that part of the Ogallala is in New Mexico, but only a part of it extends into NM by about thirty miles, in the southeast part of the state. As water is drawn from it in Texas (much, much less is used here in NM because of how water rights are apportioned), it recedes toward the Texas border. The estimates here are that the Ogallala will have receded east past the Texas-NM border entirely in about eighty years. That will leave the SE portion of NM dependent on a reservoir about 600 ft down, the Santa Rosa, which is brackish (this whole area was a salt-sea basin in the Permian age) and will have to be treated, even for agricultural use.

In the meantime, T. Boone Pickens is buying up water rights in Texas as fast as he can, so he can pump water out of the Ogallala and sell it commercially. *sigh*

Drought has also come at a bad time in this cycle. The less rain there is, the less recharge and the more farmers must draw for irrigation.

[damnraddem]

3. There was a book called 'Cadillac Desert' that predicted this ...

and worse.

[ramapo]

10. Great book

Recommended reading...

[NNadir]

4. I'm sure this isn't news to the folks posting in this section,

but water is going to be the most serious commodity problem in the twenty-first century. Indeed two of the most important and basic resources the planet has, its atmosphere and its hydrosphere are under incredible unyielding attack.

I don't know what the solution is, but it is sure that the carrying capacity of the earth for both human and non-human species is going to contract catastrophically unless we are very careful.

It is a horror to recognize that at critical time in human history, men like Bush are in positions of power.

[zeaper]

5. Money

Water=Money=Energy

Given enough energy and money we can desalinate seawater into fresh water and pump it anywhere.

Of course this does not eliminate the water problem, but I think it puts a different perspective on it.

[NNadir]

6. It's not that simple.

Desalination will certainly have profound environmental effects; specifically it will create heavy brines that are sure to impact ecosystems. (Do we really want to convert the coastal waters of California to the equivalent of the Dead Sea?) This ignores completely the fact that energy itself has a huge environmental impact. Even the relatively clean forms of energy, solar (in all its forms) and nuclear have environmental impacts.

The real solution is population reduction, preceded of course with conservation efforts.

In the Ogala case, there one ready solution: Some of the more marginal land should be taken out of production and returned to grassland. Crops amenable to drip irrigation should be adopted.

Suburban areas drawing from the aquifer should require the use of native vegatation as opposed to water intensive lawns. Then of course there's the old standards: Low flow showerheads, low flow toilets, and agressive water recycling.

[zeaper]

7. Actually not

Current desalination technology uses reverse osmosis to separate the salt from water. The result is two discharge streams, one fairly pure water the other a salt enriched water stream. No heavy brines. There are several desalination facilities in operation, the biggest are in Saudi Arabia.

I do agree that part of the solution would be population reduction and efficiency improvements in water usage. Most water (about 90%) is used in agriculture or industry so these areas need to be looked at. As for domestic use, with the exception of the water used on lawns most of the water comes back via the water treatment plant. The low flow toilets and showers are not so much water savers as energy savers.

[NNadir]

8. I know the desalination technologies available, but salt enriched is

seawater still a result of the process. The fact is that when you remove purified water from seawater, no matter how you do it, you have to dispose of a solution that is enriched in salt. This is every bit as true of reverse osmosis plants as it is for flash distillation plants and other types of systems. (Flash distillation has energy advantages in some cases since it can use cogeneration heat, although the flash distillation desalination plant at Diablo Canyon Nuclear Power Station has been displaced by reverse osmosis systems.) This change in salinity, no matter how much salt enrichment it entails is not likely to be without environmental consequences; much of the environmental impact is likely not to be appreciated until the technology is adopted on a truly grand scale. Some of these things will not become apparent until the scale is truly industrial. It is one thing to have a small city like Morro Bay, California use desalination (which it does); it is quite another to have Los Angeles do the same thing. It is still yet another to have California (or any other ocean front state) pump desalinated water to Arizona and New Mexico.

It is difficult to sort out the state of the Persian Gulf (the body of water, not the oilfields) and the Saudi desalination scheme on it. The environment there is so badly impinged by the oil industry, war, etc, that it would be difficult to attribute what the exact causes of any decline would be. I think the low population density in Saudi Arabia however is not comparable to what we will see for large scale desalination schemes in other places in the world. I note that the Saudi system, among other things, results in the injection of more Greenhouse gases into the environment.

Water that heads back to sewage treatment plants is of course recoverable, with a significantly lower cost than desalination. However we should not expect that these systems recover all the water, given the propensity for leaks, and evaporation and wasted water that results from the recovery process itself. One element of purification of sewage involves aeration for instance, a process which results in considerable lost water through evaporation, and the expenditure of considerable energy. San Diego recovers most of its water from its sewage stream, for instance, yet still needs considerable amounts of imported water. This is why water conservation devices in urban and suburban areas are nontrivial in consumptive terms.

I agree that agriculture can be expensive in water usuage terms. It is probably unconcionable to grow rice in California (if in fact they are still doing it.) Certainly one important water saving strategy will be to take marginal lands out of production, as I indicated above. The removal of the Imperial Valley from agricultural production however will probably have an adverse effect on the availability of salads in winter, however.

[Sufi Marmot]

11. Can the salt itself be recovered?

How much salt are we talking about, anyway? Could it be put to use as road salt in snowy areas (not that this is ideal for the environment but it's used nevertheless...) Could it be loaded into freighters which sail far out into the ocean and discharge it slowly over a wide area so that the effect is negligible?

-SM

[NNadir]

12. Yes, some can be recovered, but at additional expense.

Salt is recovered from seawater commercially. There are evaporation ponds for this purpose in San Francisco bay for this purpose. Seawater is a source of magnesium and many other important minerals. It can also be used, and is used, in electrolysis systems for the production of the important industrial chemical Sodium hydroxide and chlorine. (Chlorine use however is an enviromentally controversial process.) Hydrogen is a byproduct in this process, although the process is not economical when compared to hydrogen produced by water gas reactions (High temperature methane/steam). There have been proposals in the distant past to extract Uranium from Seawater as part of a desalination plan, but the price of Uranium has fallen far too low for the process to be economic, at least at the present time. One would still have to dispose of the salt. (The most serious proposal was in Japan, since all Japanese Uranium is imported.) Brines from the Dead Sea are used for the production of Bromine in Isreal, and theoretically more dilute salt solutions such as those coming from an RO system could be used for the same purpose elsewhere.

Still I doubt that this use would account for the oceanic salt balance overall in a vast desalination scheme, particular one on a scale to address issues like continental fresh water depletion.

I also have some doubts whether road salting, one of the largest uses for salt, really represents a particularly sustainable process. I actually think road salting is a bad idea, particularly in areas that have underground water supplies depending on a water table.

Seawater has from time to time been proposed as a source of Uranium.

[Sufi Marmot]

13. OK, so why not just put back the salt in a controlled manner?

I know it would be more expensive, but at least it would be a closed loop. As I mentioned above, theoretically you could put it back slowly over a large area in the deep ocean so that it wouldn't significantly increase the effective salt concentration in any given area - the salt that got added back would be quickly diluted to ocean concentrations. I'm envisioning rigging up freighters that would slowly cruise the open ocean in a regular pattern, slowly discharging salt. I don't see why it couldn't be remote controlled someday in the future (sort of like those robots that vacuum automatically...)

-SM

[NNadir]

14. Workable, but as you say, it will increase costs.

Ocean salt dumping could be used to offset salinity changes caused by melting glaciers and icecaps in the artic regions. These salinity changes are expected to have a profound effect on ocean currents, and therefore world weather. If however the ships were run on fossil fuels, this would have the effect of accelerating the greenhouse effect.

[Sufi Marmot]

15. Point noted - thanks...

I would think that the amount of ocean water desalinize to make it potable would be small compared to that added from the increased melting of icecaps and glaciers, but I could be incorrect. But if so then the amount of salt added back from desalinization wouldn't even offset the influx of freshwater, so in theory adding back the salt shouldn't be harmful if done properly. /handwaving and speculation

If however the ships were run on fossil fuels, this would have the effect of accelerating the greenhouse effect. I can envision some sort of solar-power/battery setup - the ship sails around dispensing salt until the batteries run low, then it shuts itself off while it recharges, whereupon it starts up again and continues on it's way. The whole thing could be unmanned, once it was empty it could be remotely steered back to port for another load...Whether this is at all feasible on a large scale I have no idea...

-SM

[ramapo]

9. All Over

Things aren't much better here in the Northeast.

NJ has significant aquifers that were beginning to be severely stressed during the last drought (00-02). A large aquifer underlying the Pinelands in South Jersey has been drawn down enough so that there are visible surface changes such as disappearing bogs and small ponds.

Except for the occassional drought, I used to think the Northeast wasn't vulnerable to water problems like the central and western U.S. Not true. Suburban sprawl is taking a toll, especially the proliferation of sprinkler systems.

I've always seen the pictures of the sprinklers going full-tilt in places like Nevada so they can make believe that they don;t live in a desert and thought "How stupid of them!".

Well it's just as stupid if you live in NJ. I installed sprinklers when I had some extensive landscaping done. I was astounded at the amount of water consumed not to mention the water bill (and I was somewhat conservative in my use).

So I just do some spot watering now of flowers and some bushes. Grass always recovers.