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World water resources
3

World water resources

World water resources

(OP)

In this forum we have been talking sometimes more seriously, sometimes with some superficiality, about oil, alternative energies and also global warming.

What about world water resources?

Sea and rivers pollution, underground water ponds contamination, droughts and lack of rain in remote zones of the planet and advance of the desertification. Are there a world conscience and solidarity polities and real efforts to inverse these situations?

RE: World water resources

Well, near where I live, there is something called the "Sydney Tar Pond". It has been a problem for a very long time, since the mid-1970s. They have tried to clean it up before, but with no success. However, just a few months ago, they decided that they will spend tons of money on it, a 10-year, 400 million dollar project. So I just up here in Canada, they are trying to clean up any contaminations.

RE: World water resources

Well I guess once we've got limitless energy it won't be such a problem as we can just use desalination plants.

Until that time it's an issue and you're right it doesn't seem to come up as much as green house gasses etc.

I live in the desert and it amazes me that almost every day I see water in the streets, presumably from people over watering their yards (some of it is definitely from that source).

RE: World water resources

The number one green house gas has always been and will always be water vapor.  Carbon dioxide and other gases make the news as probable mankind caused components.

RE: World water resources

It amazes me that my local region has been on some form of water restriction for about 5 years now, yet the building lobby is so strong that they still get permission to build vast new suburbs, while at the same time the water board does not build new storage facilities.

Mind you, it should be pointed out that domestic water use is a very small part (<<25%, I think it is 5%) of the total water use. I would have thought the first thing to do would be to charge the same price per tonne to all users, for the same product.

I pay about 64 US cents per ton for water, and about 80 for disposal. I also pay some ridiculous fixed charge, such that if I were to double my water usage I would only just see an effect on my bill. So, there is very little financial imperative for me to consider water use, domestically.

So one approach, which admittedly is a bit unfair, would be to fold the fixed charges back into the volumetric delivery rate, so at least there was a direct noticeable relationship between water usage and the resulting bill.

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

RE: World water resources

(OP)
International rivers can be a way of disputes between countries, especially during droughts. Each country manages water rivers according their needs. More and more river water ponds are being constructed modifying the watershed and micro climes, braking environment equilibrium. Most regions of the world live in seasonal periods of droughts and floods. I agree with flamby this can be dangerous and motif of argues between countries in the short time.  


“The bridge over trouble waters is now a bridge over a dry canyon”

RE: World water resources

If developers are not allowed to develop, then will that change at all the water cycle or the water problem?  Maybe in the new area the use of water will be better.

In my area, I would prefer if we shut the door behind me as soon as I moved in.

We happen to have a nice local support of a small water resource we have.  We could do better, but I am glad the local citizens are willing to pay for the upkeep and the loss in revenues from not developing.  However, the big picture in my area may not be as good.

I used to support the Cousteau society regularly, but since The main man passed away I lost interest.  Is the society still around?

Is it acceptable for an engineer in good conscience to support the Sierra club?  They do a great job IMO in our local area.  I am concerned about their misdirection (IMO) at the national level, it seems to me they have been subverted with a bad political agenda and do not have holistic solutions to offer.

jsolar

RE: World water resources

I agree about the Sierra Club.  They seem to have an agenda driven by urban dwellers with guilty consciences.  They want to make it so they can take a week's vacation and keep the locals out, when the locals live there because they have abandoned (or have no interest in) the high dollar urban lifestyle.

Then, they have no concern about the rural lifestyles of the people whose water they take.

Water will be the big question this century - not oil.  Oil we can find alternatives for that just cost a little more.  As land is stressed and arable land destroyed, there will be less transpiration, so less rainfall.  It's a vicious cycle led by overpopulation.

RE: World water resources

2
"Water will be the big question this century - not oil.  Oil we can find alternatives for that just cost a little more.  As land is stressed and arable land destroyed, there will be less transpiration, so less rainfall."

I have heard this kind of rhetoric often, and I guess I don't understand the logical basis for it. It seems like an emotional response to me.

3/4 of the earth is covered in water, how can anyone say that water is in short supply, or hard to get? Rainfall has never been a characteristic of southern California, so people moved water from the mountains where it is pleantiful to the valley, and started planting crops. Why not move it from the oceans if the mountains don't get the snow?

Now don't get me wrong, I understand that rainfall patterns change, and that it's silly to build large cities in the middle of the desert southwest in the US. But it seems to me that these are problems that solve themselves. Over time as the resource becomes scarce, either the population migrates to places where it is not scarce, or the bright people that post here solve the engineering problem.

Desalinization is merely a matter of energy cost. In the middle east they do it all the time.   

-The future's so bright I gotta wear shades!

RE: World water resources

I agree with sms on this.  We are not going to use up all of the water.  We may have trouble finding potable water, but that is a matter of the energy required to make it so, not the lack of water.

RE: World water resources

LCRuiser, we agree on the Sierra club, but I disagree on assuming overpopulation.  I rather think it is man's inhumanity to man that could be reduced and thus make for better living for all.  We will always have the poor.  Children are the only real social security.

I plan to write to the Sierra club.  I think they do a great job locally; they have done very good work in Illinois (at least from reading their web site and talking to their local people).  I am worried about supporting them because of their national and global agenda that does not seem to relate to their prime purpose.  

I would appreciate any comments, insights, or words (I will plagiarize you in the letter, so do not send anything that you do not permit to have repeated to them) in a letter to them.


sms,
Very good insight.  I had never thought about it as an energy dfriven issue.  Thanks.

jsolar

RE: World water resources

(OP)

Although desalination can be used to bring potable water to desert hostile regions there are some concerns that must be taken into account.

Desalination is a very old process first used in longboats travels and in industrial waste treatments. There are already lots of desalination units producing potable water.

“Desalination is the process of removing dissolved minerals (including but not limited to salt) from seawater, brackish water, or treated wastewater. A number of technologies have been developed for desalination, including reverse osmosis, distillation, electro dialysis, and vacuum freezing.

Environmental impacts associated with concentrated waste discharge have historically been considered the major environmental concern with desalination plants. By some estimates, a desalination plant at could produce 1.5 billion liters of brine a day to be released back to the ocean.

Further, desalination plants produce liquid wastes that may contain all or some of the
Following constituents:

• High salt concentrations, chemicals used during defouling of plant equipment and pre-treatment, and

• Toxic metals (which are most likely to be present if the discharge water was in contact with metallic materials used in construction of the plant facilities).

Liquid wastes may be:

• Discharged directly into the ocean;

• Combined with other discharges (e.g., power plant cooling water or sewage treatment plant effluent) before ocean discharge;

• Discharged into a sewer for treatment in a sewage treatment plant, or

• Dried out.

The environmental impacts of liquid waste treatment will vary depending on factors including the location of a desalination plant and method of waste disposal. Potential environmental impacts resulting from the increased turbidity, reduced oxygen levels and increased density of any discharged wastewater would need to be fully addressed.
Desalination plants also produce a small amount of solid waste (e.g., spent pretreatment filters and solid particles that are filtered out in the pre-treatment process) that would have to be disposed of in landfill.”

RE: World water resources

... but you still won't run out of water.

RE: World water resources

just as we won't run out of food ... food (and water) will either be expensive or not particularly clean.

so if you were a country with poor water beside a country with good water ... won't you want some ?

your neighbours upstream always have the advantage !

RE: World water resources

As I said, it's a matter of energy cost, so now back to talk of oil crisis.....

BEIJING (Reuters) - Drought-stricken China, where hundreds of millions of people are without regular access to drinking water, is turning to desalinated sea water to help end the crisis, the government said on Tuesday.
 
Apart from widespread drought, factories have ignored pollution hazards and dumped toxic industrial waste into rivers and lakes in China, home to one-fifth of the world's population but only 7 percent of its water resources.

"China is expected to desalinate 800,000 to 1 million cubic meters of sea water per day and use 55 billion cubic meters annually by 2010," the State Development and Reform Commission said, detailing China's ninth five-year plan.

China desalinated 120,000 cubic meters of sea water per day last year.

It was not immediately clear how China, which is also desperately short of fuel, would power the energy-hungry desalination plants.

More than 600 medium- and large-sized cities in China were now suffering "serious water shortages," Water Resources Minister Wang Shucheng said this month.

China is investing billions in a project to transfer water from its lush south to the arid north.

The so-called western route of the project could involve harnessing rivers cascading from the Tibetan highlands in the Himalayas to quench the thirst of Qinghai province and other poor western areas.

But Wang said the proposed system of tunnels stretching 300 km (190 miles), and costing more than the $25 billion Three Gorges Dam hydroelectric mega-project, was unnecessary, unscientific and not feasible.

-The future's so bright I gotta wear shades!

RE: World water resources

Even if you don't want to desalinate by cleaning waste water (sewage) to a level high enough to at least use it to water crops would probably help.

Seems crazy that many water treatment plants clean the water to a level where it's supposedly safe to swim in but then dump it out to sea?  Especially anywhere prone to droughts.

RE: World water resources

We can have enough water if we have enough energy. It goes back again to same oil and energy topics again...

Ciao.

RE: World water resources

(OP)


Lack of water is being a real problem in most regions of Africa. Lots of people are dying thirsty. We can’t live without water. I am not so sure if actual energy resources mean more water in quantity and quality. Because of acid rain the hypothesis bellow will not be the solution

RE: World water resources

"Acid Rain" as experienced in New England region is potable.

RE: World water resources

(OP)
In New England region the control emissions of sulphur dioxide and nitrogen oxides are starting to pay off. The switch from coal to gas in both power generation and in the home, while being mainly for economic reasons, has also meant a lot less pollution and as consequence less acid rain.

RE: World water resources

No worries!  Technology will fix everything ;)

RE: World water resources

(OP)
I supose all of us tend to burying the head in the sand in the hope that some future technology will fix everything.

RE: World water resources

Fresh water is nothing other than another form of stored solar energy.  And just like the other forms of stored solar energy (i.e. fossil fuels etc.), it's distributed by geography and geology- and we're mining it at an unsustainable rate.

Charge more for water use and it will be conserved better.  Charge more for water disposal and people will find ways to re-use it more often.  Same goes for atmospheric dumping of contaminants etc.- no cost equals free equals excessive use.  The market doesn't conserve things that are not assigned a cost.  Real costs of one person's consumption are imposed on others who are not involved in the transaction.  Taxes are the only way to fix this failure of the market to assign costs equitably.  

RE: World water resources

In the solar power thread I asked if anyone could suggest a good way of storing solar power.

It strikes me that a domestic drinking water system, solar powered, might be a cost effective way of 'storing' solar power.

Here's a truly terrible example:

Run all your grey and black water out into the back paddock, as is known technology.

Now, set up solar powered cold plates above the back paddock.

The water evaporates off the paddock, condenses onto the cold plates, voila, drinking water (or at least very clean water to use as the first step in a drinking water system).

As usual the devil is in the details. Is this a better cradle to grave solution than centralising waste management? or desalination? I don't know.

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

RE: World water resources

I'm surprised nobody has mentioned the following expression, common in the Western US:

Quote (Mark Twain (attributed)):

Whiskey is for drinking, and water is for fighting over.

Also, the Aral Sea, which has lost 60% of its area and 80% of its volume due to Soviet irrigation projects, is a prime illustrationof the effects of manmade water diversions. http://en.wikipedia.org/wiki/Aral_Sea

And North Africa was a major wheat producer for ancient Rome, 2000 years ago.  And a few thousand years prior, there were lush forests where now is desert.  So, some natural climate change, plus effects of man and his beasts (overgrazing causing desertification), especially in the sub-Sahara Sahel:
Water Stress in Sub-Saharan Africa
http://www.cfr.org/publication/11240/

And in the central US, the large Ogallala aquifer has dropped as much as 400 feet (in Kansas) as the water is mined for irrigation. One USGS prediction: "Almost all the central and southern High Plains would be unable to run center-pivot irrigation by 2020..."
Also, "Over 700 miles of perennial streams are now seasonally dry in Kansas, as their water seeps away into dry sediments." http://www-geology.ucdavis.edu/~cowen/~GEL115/115CH18miningwater.html

So, water resources is indeed a worthy subect for Eng-Tips!

RE: World water resources

And Mono Lake is virtually drained for Los Angeles drinking water.  A good book on the water wars of the western US is "Cadillac Desert" in which the author, indeed, mentions the saying "Whiskey is for drinking, and water is for fighting over" but it's a western US idiom, and not originally from Mark Twain.

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