Getting Fresh Water

[Artabus]

Hi guys

In all the posts, and newsclips, I have not anywhere seen any comments about how to turn all the dirty flood water into something drinkable. Warnings about bottled water running out, or storing tap water, are all very well, but some basic advice to people suffering might be a bit more useful.

In that vein, here are my suggestions as to how people can help themselves. Grateful to anyone who can help get the message out, and please feel free to add your own suggestions!

Rainwater collection

Rainwater can be drunk, although it is wise to boil it first. This is because it will have picked up pollutants as it passes through the air. Use as large a catchment area as possible.

Condensation

Distillation

Pass a tube into the top of a water filled container, placed over a fire, and the other end into a sealed collecting tin. This second tin should preferably be set inside another container providing a jacket of cold water to cool the vapour as it passes out of the tube. To avoid wasting water vapour, seal around the joins with mud. This method can also be also be used to distil urine (which should never be drunk), although it may be too concentrated to yield much.

It should be clear that if you heat the floodwater in a roof based collector/reflector using a setup similar to the above, the water will evaporate and the condensate is then drinkable. This method will yield better water than boiling and a simple filter.

Some ingenuity in terms of the kit used may be required, for example if the family in question is stuck on a roof. For this reason, working together in community would yield better results than a go-it alone approach.

Solar still

Set up a container approx 90 cm across and 45 cm deep. Place a collecting can in the centre, then cover with a sheet of plastic formed into a cone. Roughen the underside of the sheet with a stone to ensure droplets run down it. Insects and small snakes may also be attracted and become trapped, so support the collecting can so that it cannot be knocked over. The sun's heat raises the temperature of the air, and vapour is produced. As the air becomes saturated, water condenses onto the underside of the plastic, running down into the container. This method can be used to distil pure water from poisonous or contaminated liquids. If possible, use a siphon to a lower level to draw off water without disturbing the sill.

Plants (for those areas that have any)

As plants grow they release water into the air, placing a plastic sheet over a number of plants or trees fashioned into a tunnel leading down wind, the gathered end then be cooled by connecting it to a large pipe taken into and out of a brackish or contaminated pool. This acts as a condenser for the water laden air driven through it by the wind or breeze. The U-shaped pipe can then be carefully emptied into a receptacle from time to time supplying drinking water for many people.

Cut vegetation placed in a large plastic bag will produce condensation as it warms up. Keep the foliage off the bottom, and away from the sides of the bag. Place the bag on a slight slope to encourage the condensation to run down. Keep the bag taut with a stick.

Even polluted plants will only give off water.

Heating

Where no materials, gas or electricity are available to provide heat, use solar concentration. Use reflective materials or tinfoil to focus the sun's rays onto the water to be distilled. Be aware that this produces very high temperatures.

Reducing water usage

Remember to ration your sweat, not your water. If you have gone a long time without water, take it in sips not gulps. Large gulps can cause vomiting. Eat little, as eating consumes water. Don't smoke, don't talk, don't drink alcohol, minimise movement.

Let's keep the politics out of this thread please... The situation is as it is, so it's solutions time.

Edited October 25, 2011 by Artabus

[BKKdreaming]

Hi

not sure if you know but how well will the reverse osmosis systems work to filter the nasty flood waters in Bangkok now ?

is a 3 stage one enough , Pre cleaner, charcol filter that takes out the clorine that would damage the RO membrane , and the Reverse Osmosis stage itself ,

Thanks for posting the first part

BK

[Naam]

The situation is as it is, so it's solutions time...

...drink beer!

[Artabus]

Hi

not sure if you know but how well will the reverse osmosis systems work to filter the nasty flood waters in Bangkok now ?

is a 3 stage one enough , Pre cleaner, charcol filter that takes out the clorine that would damage the RO membrane , and the Reverse Osmosis stage itself ,

Thanks for posting the first part

BK

Hi

Let me come back to you later this afternoon (Bangkok time) please, In the meantime, who is the RO system manufacturer and what is the model number? How long have you been using that specific membrane?

Thanks

A

[Nisa]

http://biotech.law.lsu.edu/cphl/practice/water.htm

[BKKdreaming]

Hi

BK

Hi

Let me come back to you later this afternoon (Bangkok time) please, In the meantime, who is the RO system manufacturer and what is the model number? How long have you been using that specific membrane?

Thanks

A

its more an overall question , I would probably bring new units from the USA but wonder if they will make "swamp water" into drinkable safe water , I know they will make good water a little cleaner , but I cannot find out how bad the water can be before the RO will not work good enough

BK

[Artabus]

its more an overall question , I would probably bring new units from the USA but wonder if they will make "swamp water" into drinkable safe water , I know they will make good water a little cleaner , but I cannot find out how bad the water can be before the RO will not work good enough

BK

The flood water will have chemical run off from the fields, dead animals, more diseases than I can think of, heavy metals, all mixed in with the contents of sewers and canals. Does reverse osmosis clear that lot?

The good news is yes in theory. The bad news is in practice it possibly does not.

It depends entirely on the membrane and how new it is / whether it has been serviced.

Properly selected reverse osmosis membranes will give you water and only water - that's drinking water - from all predominately water based solutions. They may even in some cases be the best method of drinking water extraction.

It really does come down to the membrane. There are a lot of different types, so do your research is my advice.

A good membrane can last for years, especially if it is flushed regularly, and simple tests can be attached to the regular use of a membrane to monitor the performance. You should select equipment where the method of changing these components is quick and easy to do in the field.

Alternatively you can buy just the RO membrane and then use a pump to drive the water through it.

The pump can be one driven by hand (useful if the electricity is out), and you just have to make sure that it reaches the pressure required by the RO membrane. If you use eg two pumps together, just add their respective "heads" (a measure of pressure) to work out the total pressure obtained.

[Artabus]

http://www.industrialwaterequipment.co.uk/reverse-osmosis-article5.html

to illustrate the point.

[BKKdreaming]

thanks for the link......

I just wonder how the street water machines are servised ,

and then if the city water gets worse will the street water machines still help,

I see many people depending on them , and really have my doubts

I will see how it goes in BKK and see if I need to bring a couple RO systems over to help out friends

BK

http://www.industrialwaterequipment.co.uk/reverse-osmosis-article5.html

to illustrate the point.

[Artabus]

thanks for the link......

I just wonder how the street water machines are servised ,

and then if the city water gets worse will the street water machines still help,

I see many people depending on them , and really have my doubts

I will see how it goes in BKK and see if I need to bring a couple RO systems over to help out friends

BK

I would definitely also have my doubts. Which is why I suggested a simple distillation process; for extra certainty the two processes could be combined.

Or tablets such as these could be used

http://www.aquatabs.ca/

In extreme situations, a degree of flexibility is of course required.