With the Katrina aftermath, the water supply in the New Orleans area is extremely polluted. Is it possible to make the water potable? If so, what is the best method(s)?

I would guess that the solids and petroleum products would need to be filtered out first. Maybe by straining through sand then charcoal would do that? Would a water filter or chemical tabs work then? If these won’t work then what, if anything, would?

I am going back to my wilderness survival classes for this but that did not deal with the mass of contamination that is there.

Thanks

If you're talking about the water filling the streets, it's salt water and no amount of filtering can make it drinkable.

Drink fresh water that's being brought in by truck. There's more and more of it now, in insane 1/2 liter bottles. The Red Cross is getting thousands of these bottles and also thousands of 1 gallon and 2.5 gallon bottles. But they're only giving out the 1/2 liter ones, in order to keep you dependent on them, I guess. They're using the larger bottles to flush toilets with, according to a guy on CPF who visited one of their centers.

Would this solution have been effective in NO right now?

I think the water down there is not potable at all. And it's being dumped back into the canals...yipes. A raw sewerage/rotting flesh/petroleum cocktail..deadly combination.

All the desalinators I am familiar with, including these manual operated units, will not cope well with water polluted with industrial contaminants. In particular, petroleum products especially will destroy the RO membrane. So, they would probably not work well in NO.

Yikes. It soulds like the best bet would be to do a "solar-still" type contraption, even if you use a fire to evaporate the water.

And even that might not work well if some of the pollutants have a boiling point around that of water. If so, then you wind up evaporating and condensing the polution along with the water.

I wonder how this would work: First, ignite your water. i.e., burn off any floating combustable contaminants (would this work???) Then filter large junk with paper coffee filters or similar. Then filter smaller stuff with a hiking/backpacking type filter. Add some chlorine. Then get you one of those external aquarium cannister filters that contain a significantly sized carbon cartridge. Not the small ones that hang on top of an aquarium, but the bigger ones that pump several hundred gallons per hour. The one I use on my aquariums holds a good pound or two of carbon (that you buy seperately). Run the aquarium filter on your water in a bucket or something so that the water is recycled through the filter many times. You'll need minimal AC power to run the aquarium filter. A car battery and small inverter should do it. Then desalinate if you have one of those contraptions. Boil the result.

Holy cow! All that for a drink of water. And I don't even know if it would result in something potable.

...Or your could store water in gallon jugs at a cost of about .10 to .50 gallon. Plus filled buckets, hot water heater, tub, toilet tank and other home sources

Plan ahead.

The combustion byproduct will kill you quicker than the raw materials.

"Or your could store water in gallon jugs at a cost of about .10 to .50 gallon."

True, that would be much better. I was thinking of this more as a mental exercise of "How would you purify this stuff?" It would not be a trivial undertaking. Large scale desalination is tough enough on it's own, but add chemical pollution to the mix and the problem magnifies exponentially.

I tried at home the method of distilling water by collecting the steam of the boiling water on a cloth placed over the top. You use sevelal cloths if possible one after the other and lift them off the pot with a stick to avoid being scalded. When they have cooled, you wring out the pure water in them.

I gave it a quick try by placing a handkerchief but the steam literally passed through it and the handkerchief never got wet enough. I also scalded one finger.

As Martin pointed out, some chemical substances could be distilled at the same time and it would take too much fuel anyway. It's certainly not possible if you are sitting on a roof, etc. The best is to store water.

Frankie

Heck, why not just store the hydrogen part, and burn it in an oxygen atmosphere when you want water?

<img src="/images/graemlins/grin.gif" alt="" />

"Heck, why not just store the hydrogen part, and burn it in an oxygen atmosphere when you want water?"

Reminds me of a chemistry class way back in high school.

We had seperated water into hydrogen and oxygen using electricity and had the gasses stored in those round glass things with long snouts (forgot the name of that glassware). Someone asked the teacher, "Can you turn it back into water again?"

He said "Sure!" and whipped out his lighter. Next thing he said, as he was rising from the floor behind his desk, was "Am I cut?! Am I cut?!" We never found the resulting water. Just glass fragments all over the place. (Nobody was hurt, luckily!)

He did it way too fast. This is why fuel cells are going to be so awesome. Hydrogen in, water and electricity out.

Sorry I didn’t get back sooner. My internet connection died.

I agree that storage of water is the best approach to an emergency prep. I myself do have some jugs of water stored for that purpose. I sit high enough that flooding is not a problem however, a power outage shuts down my well. My original question was asked of me and I couldn’t answer it with certainty. That is why I came to you folks. I was not sure if any means of filtering or chemical treatment would work. I wonder if someone will be working on this issue, now that this has happened, in preparation for a similar disaster that hopefully won't happen.

BTW: The EPA has done some water sampling and posted the results here.

The witches brew in the streets of NO there is no way you could purify it. It just has too many diffrent mixes for any one or even several methods to work.

Distilling would be best to remove disolved solids. Salt or other like chemical cpompounds. Also any bio contamination. As they can be treated as solids. But volitile liquids such as patrolium would go along for the ride. It you had the wherewithall to set up fractional distillation some of thes would be removed.

Then you would have to run it through a charcoal filter. This might remove most of the volitile contamination. Patrolium being the worst.

Then a reverse osmosis filter to clean it further.

Then maybe a second seperate charcoal filter.

You might end up with something drinkable. But and its a big one fith some of the stuff mixed in fromm chemical plants and even household chemicals the chance are still far too great that it might still be a leathal drink. I would not trust it.

Has anyone tried Polar Pure? I'm thinking of getting a bottle. It has a long shelf life, even after use, and treats up to 500 gallons of water. I'm thinking it would be a good backup to my MicroPur MP1 tablets.

Okay, back to chem 101 eh? Here goes.

In order to electrolyze water into hydrogen and oxygen, you need to start with a pure source. If you use contaminated water, you will be electroyzing these molecular compounds as well, and your off gas production will be corrupted and unusable. It could also quickly ruin your electrolytic screens (fuel cells thus require pure water, or other pure polar hydogen molecular compound).

As for distillation, it is not whether another substance has the same boiling point as water, but the same condensation point as water, that will cause problems with purity of the process.

My suggestion is to pump all that sewage back into Lake Ponchatrain, add copious amounts of aerobic and anerobic bacteria, stir often, and let it all get digested over the next decade or so, then rebuild the ecosystem to deal with what's left. In a hundred years or so, we could then dredge the lake bottom to remove all the heavy metal precipitates and undissolved hydrocarbons, send these to the smelter, and things would be back to "normal"??? Nothing cleans up contamination so well as Mother Nature at work, it just doesn't go according to our relatively short timeline is all. Even DDT gets broken down in time.

The truism "the solution to pollution is dillution" is usually true.

This is what I was wondering about when they starting pumping all that garbage out of NO. Didn't seem like a terribly good idea to put it back in nearby lakes, but I can't say I have a better idea. Draining the flooded city seemed to be a top priority, but I don't understand why. Reports were that everything was totally destroyed anyway. But trying to treat all that polluted water would have been nearly impossible, so what else could have been done?

The flood waters are ridden with disease, and it only gets worse the longer it stays there. It's as simple as that. As soon as that water is out, they will probably start spraying for mosquitos big time.

Yes, Mother Nature. If you know how she works, she will take care of you no matter what the situation is. <img src="/images/graemlins/grin.gif" alt="" /> <img src="/images/graemlins/grin.gif" alt="" />

A sand filtration system will work if the water doesn't contain saltwater. It takes
some time however for the bacteria in the system to get used to digesting the
oils, etc. About 2 weeks. It is what many sewer plants use and it is a good method in 3rd world
countries for home use.
http://www.cawst.org/technology/watertreatment/filtration-biosand.php

3rd world countries? It's what's used in Minneapolis, at least until the new micro-filtration system is fully up to speed.

I would guess the sand filtration gets rid of the "chunks" and it is chlorination that does the actual sanitation -- much like a for a pool. I don't think sand filters or chlorination can take care of nasty chemical/petroleum products in water. Most cities are careful to take water from relatively clean sources.

With Regards to "Polar Pure"
I have used this, It is an Iodine treatment so you will have the iodine taste unless you add some other flavoring. Another downside is that when stored with other items in you pack for long periods of time it will turn things brown....even with the cap tight.

You may want to check out this site for how slow sand filtration works:

Slow Sand Filtration

Pete

Makes sense, considering I have a sand filter unit on my 35K gallon pool at home. Once you nuke the water with algaecide and chlorine, the sand filter makes that water pretty crystal clear. Of course, we're talking about a pretty closed system. I'd hate to see what two or three quarts of motor oil, some cooking grease, some raw sewage, and various other household chemicals would do to my pool.

We have aeration filter systems on our sewage treatment plants at home, similar concept to the sand filtration. One thing that really hurts their operation is when someone pours a bunch of toxic chemicals down their drain and it kills all the wee beasties in the tanks and basically brings the process to a halt until the sewage can be decontaminated and new microbes installed. Same thing can happen in a septic tank (ugh).