As I mentioned in the Food Riots post previously, I lived in Louisiana during hurricane Katrina.
Growing up in a place where super storms with massive winds, tornados with a high possibility of power outages, miscellaneous contanimation risks, and general frustration, fear, and panic got me a bit of education on this stuff.
I was born learning about what to do if the power is out, what to do if there is not fresh water. Even though I lived in a community pretty far inland- the security procedures, notifications and general warnings were very important and broadcast, especially in areas with evacuation orders (because, due to economic, spiritual, personal and medical reasons, will not leave).
So- what were we told to do?
1) Chemical Purification tablets. They are like a few dollars, easy to carry, lightweight, useful for immediate emergencies. I keep some, even in Chicago, just in case I have nothing else. It will kill most anything, and used short term is better than all the water borne diseases that urban places with clean water even more susceptible to. Seriously, it is in my first aid kit. Maybe its being born in hurricane country, but I wouldn't be without these things. Available commercially in pretty much any camping store.
2) Have stores of bottled water. Clean containers well (like the comic said) before hand, fill them up, keep them sealed as possible. (in an emergency, prepping water to sit out covered in a cleaned container for 5-10 days is WAY safer than outside water). Replace stored bottled water. Contaminates do leek into water, and it is a problem. One of the ways to work with that is to replace water containers once a year (6 months is also a widely referenced change out point). The water is still (usually, if you have a good bottling manufacturer) clean and usable, but the longer you wait the more likely it is to have weird stuff you don't want to drink.
3) Clean and Fill the bathtub. Very useful. Larger container. Can be used for plumbing purposes, also cooking and water drinking. As long as the main is intact, a toilet will flush if you put water in the tank. But- do so rarely, because it takes a good amount of water to flush a toilet. Course, if its just going out into the street, picking a spot (its even better if you can bury) outside and going there is better, in terms of water conservation. Indoors (like the Super-dome) going to the bathroom in a particular area is safer (after the bathrooms were rendered unusable, and more preferable, just b/c human waste can transfer a lot of diseases, and it being everywhere is not good) if it can be sealed, even better.
4) If you cannot get clean water- Filter- boil, filter. Its generally good to filter before and after because it removes larger particles and then gets out other stuff. Of course, the second filter should be a clean filter! Plus, it makes it easier for us spoiled Americans to drink. Boiling will kill most things. It is not perfect, but heat removes alot alot alot the most dangerous things.
5) Set up a simple distilled water tarp. Essentially a tarp above the ground held up by the four corners. With enough room to dip in the center to hold water. Make sure tarp is secure so it doesn't break! Works great in Emergancy enviroments, and is a source of clean water 1x day from the air. Can help stores last longer. Indoors, it should probobly be close as close as possible to an open window. Ususally used when trapped in a forest or that kind of enviroment, but useful non-the-less.
6) Distill water through boiling. This is not very efficent, but useful for REALLY contaminated waters. Essentially a cover over a pot with that will not melt (with a single h*** in it), put some flexible tubing (like, removable shower head tubing can be used in a pinch) into another container. The tubing needs to go up a little bit, then curve down into another container. As the water evaporates, the steam will go into the tube, condense and leave things like salt, various toxins, dirt behind. Then it is drinkable. If you have a metal container, you can place it on a fire while you cook something else, that has tubing that goes into another metal container. But doing this constantly, most likely you will run out of fuel and fast.
7) Canned foods- especially fruit and veggies- have water in them. LOTS of water. Drink it. You want to drink things with low sugar and low salt. The higher sugar content and salt can dehydrate you further. So, when you eat something, drink the water it comes with. Do not waste! Fresh fruits and vegges generally have lots of water in them also.
8) NO CAFFEINE. NO SALT WATER.
8) Stripen (a product) and filter! Uses UV (I think) radiation to kill things in water. There are a bunch of variations of these. Some of them are power intensive, some of them have solar attachments, some of them use batteries. Anyway- know the power constraints of these things, and have one on hand with the necessary power supply (batteries, portable solar power).
9) Camping buddy says, using decaffeinated tea bags (note, the no caffeine rule) can help cover weird tastes after water has been cleaned. So, if you have the time, sitting it overnight with a teabag and then drinking it makes it more tolerable.
10) Dehydration can kill you in 3 days. Many, many many water borne diseases make this faster. If you have a choice to do any of the above, start immediately, not waiting until day 3. The more dehydrated you get, the more cognatively impared someone becomes and contanimated water will become more and more desirable. Most likely, Your body will will NOT allow you to sit there and die without trying the dirty water.
11) Be prepared. The more prepared you are the better off you will be. Urban areas are very very very dangerous due to the high concentration of people, and water purification is not exactly efficient. By day 3- people can be very sick, dying, confused and irrational with very very little to no water.
this site goes into water rationing while camping. Though, it assumes to some extent that you'll have some source of water. This discusses being in a desert http://www.essortment.com/hobbies/survivedesert_tvgn.htm
. Water needs differ from person to person, so if you are very active you will need more water than someone in the shade. staying still.
What do I think the best water purification tool is? I really do not know. But what I do know- is being prepared, knowing different options and understanding the resources and plans that are possible in whatever environment you are in is very important.
Many of these solutions are not permanent, and not perfect. Long term, it is unsustainable. But, quick short term stabilization is vital due to the limited time frame of dehydration, and the quick onset of all kinds of water related illness and death.