Doomed

[Gotte]

Can you tell me, Mark, just as a point of interest, how is water purification and distribution affected in this sort of catastrophic scenario? I always just assumed that it was a pretty simple system (gravity fed, enzyme and chlorine treated).

Thanks

 

[hogstable]

If you think about how interdependent we are for more than 5 seconds you think thank heavens it all works because if it didn't it would really really hurt.

Hurray for civilisation I say!!!

 

[British Red]

Can you tell me, Mark, just as a point of interest, how is water purification and distribution affected in this sort of catastrophic scenario? I always just assumed that it was a pretty simple system (gravity fed, enzyme and chlorine treated).

Thanks

Nope, without power it stops. As do many sewr systems, the gas supply, petrol supplies, line phones immediately, cell phones within 24 hrs etc.

 

[cbr6fs]

Can you tell me, Mark, just as a point of interest, how is water purification and distribution affected in this sort of catastrophic scenario? I always just assumed that it was a pretty simple system (gravity fed, enzyme and chlorine treated).

Thanks

Fantastic question.

I had remembered some somewhere that water treatment consumes a VAST amount of energy, but after a quick search it really surprised me.

First off i have no experience in this field, my answer is made up 100% from articles i have just read.
From this article it states that around 4% of the national (USA) power is used to process and move water.
In general it states that 80% of a water treatment plants costs are electricity.

I'm guessing this must be an average as pumping water out from ground based supplies will take more energy than surface water, desalination plants will also consume a vast amount power over fresh water treatment plants.

So it seems that if we loose electricity not only is our ability to mass treat fresh drinking water lost, but so is our water supply system.


I'm pretty sure like me many of you are thinking, no worries i'll boil the water on my wood burning stove.
Here are some more interesting facts.

It requires 4186 Joules of to heat 1 kilogram of water by 1 °C

So lets say water temp is 10c and we want a rolling boil to treat it, so to make the maths easier for me we want to increase the water temp 100c.
100 x 4186 = 418600 joules to boil 1 litre of water at 10c

Or as maths is not my strong point 0.4 mega joules

A average hardwood has around 14.89 mega joules per kg.
Obviously a wood burning stove radiates heat in other directions so it's not 100% efficient, but we are just talking rough estimates here so lets say it's 50% efficient.

That gives us a rounded off 8 mega joules to per kg.
0.4 mega joules (needed to boil water) / 8 mega joules of energy given out by our wood = 0.05 kg (50 grams) of wood needed to raise the temperature of 1 litre 100c

Lets say we need 2 litres a day.
2 x 0.05 kg = 0.1 kg of wood per person per day

I think i said there are 12 million living around London.
That's 12,000,000 x 0.1 = 12,00000

Or 1.2 million kg (around 1300 short tons) of wood needed per day to provide drinkable fresh water to the population of greater London alone.


Scary stuff.


Cheers
Mark

 

[cbr6fs]

Should also point out.

If the worst does happen, bleach will be more valuable than anything else in my opinion.
Not only is a fantastic disinfectant, add a small amount to water and it will kill a vast majority of viruses and bacteria.

Tastes like ****e but there is not many things of this world that can survive a soak in the stuff.

 

[British Red]

But bleach has a relatively short shelf life - and loses efficacy thereafter. Calcium hypochorite powder lasts indefinitely. Just saying

 

[cbr6fs]

But bleach has a relatively short shelf life - and loses efficacy thereafter. Calcium hypochorite powder lasts indefinitely. Just saying

Good advice.

Seems that bleach is pretty much useless after 1 year.

Only application i can see for Calcium hypochorite is as pool cleaner though, which is ok if your prepping but if that poop has already hit the fan can it be found in any other products?

 

[British Red]

I use it to make a solution for sterilising home brew equipment, cleaning outbuildings etc. You can use it to make a "bleach equivalent" - a little goes a loooooooong way. Bleach is mostly water and heavy to transport. Buying the powder makes it cheaper to move and hence buy. Its not a common thing, but if you use a lot of bleach in cleaning, worth investigating.

Red

 

[Gotte]

How about ammonia? Could that be used? I seem to remember in pre industrial times, ammonia was made by adding woodash to urine and leaving it to stand for a couple of weeks. Not a very pleasant prospect, but like much else in this area, I have no idea if it would be safe. I know that you're not supposed to mix bleach and ammonia (I'm assuming there's some chemical reaction), but does ammonia have similar properties as bleach in the bug killing department?

 

[cbr6fs]

My understanding is that Ammonia even at levels that will be extremely harmful to humans, would still not kill many many organisms and bacteria.

To my mind you'd be better off removing your dirty socks and filtering the water through them rather than use Ammonia.

 

[British Red]

Bacteria will actually act upon ammonia

http://www.freshwatersystems.com/s-265-ammonia-in-water.aspx

 

[cbr6fs]

Bacteria will actually act upon ammonia

http://www.freshwatersystems.com/s-265-ammonia-in-water.aspx

It really depends on many things like the levels of ammonia, sunlight etc.

As a tropical fish keeper i can tell you Nitrates, Nitrites, and Ammonia are akin to swearing in this hobby :tapedshut