View Full Version : Rainwater collection from tarps- Safe or not?
After posting a thread about collecting water from my tarps (http://www.bushcraftuk.com/forum/showthread.php?t=21899) a comment came up that gave me pause for thought. :dunno:
I remember reading/hearing/seeing something about the treatment on bashas/tarps to be harmful for drinking, straight away, after run off collection. Maybe something about he IR treatment?
Nick
My questions are how safe is rainwater from a tarp? and if chemically safe, how much treatment do you think such water would need for drinking?
I've personally never worried about it before but what do you think?..:confused:
I think that depends on the coating of your tarp, aswell of the place of the rain; the rain in more urban areas is more 'toxic' (don't know the exact word :P )
But I think, in most areas, it's enough to boil it, but I might be wrong :)
Eric_Methven
02-06-2007, 09:35
It would be prudent to find out what chemical treatment (waterproofing, fire retardant etc) the tarp has recieved in manufacture.
In emergencies, and in times past, sails and other large pieces of cloth and canvas have always be used in collecting rain water during droughts and after dry spells. Now in the past, canvas was just that, canvas. No treatment, no chemicals so no contamination problem from that source.
I'd feel OK using water that drained off my Tatonka cotton tarp, but I'd filter and boil it first. I'd also have no problem with water collected from a polyprop (B&Q type blue tarp) tarp.
I think most tarps would be OK for collecting water from so long as it wasn't standing water. The amount of time rainwater is in contact with the tarp is minimal if it is just draining straight into a container.
If in doubt, don't use it except for washing. Although I feel that even that is a bit overkill on the side of safety. I've drunk water from tarps on many occasions without any treatment whatever and I'm still here.
You're either a risk taker by nature or you play safe and minimise risk wherever possible. So it comes down to evaluating the percieved risk and acting on your instincts.
Eric
Too Much Kit To Carry
02-06-2007, 09:38
Hmmmm - not sure about what chemicals might be passed onto/into the water from the tarp/basha.
I'd prolly run any water collected this way through my Pre-Mac - not because of the potential problems caused by the tarp but mainly because of bird droppings - the birds seem to like my tarps :umbrella:
Phil.
The Joker
02-06-2007, 09:44
Its the rain that drips off all the leaves with all the insect poo before it lands on the tarp that would concern me the most.
But I would play on the safe side and take it to a rolling boil first.
The Joker
02-06-2007, 09:48
Bird poo........didn't think of that one Phil..............
Ther'es just to much poo in this world............:yikes:
firebreather
02-06-2007, 10:10
It should be ok as others have said. The water is not in contact with the tarp for any length of time. As an old friend of my dad's used to say boil,boil and boil again.:D
litefoot
02-06-2007, 10:44
if the water drains onto the tarp after running through the trees will it be contaminated with tannins?does anyone know if this might be the case.
litefoot.:confused:
Ogri the trog
02-06-2007, 11:08
I'm like most here,
I'd trust water off a Tartonka before a plastic tarp, and a plastic tarp above a military one - though surely any coatings would be washed off after so many drenchings. Animal residues and tree leachates are a concern, but then there are newts and frogs living in my well as well as the occasional leaf that drops in - so boiling would take care of these in the field as much as any filter/UV treatment system in the house.
I recon just be sensible - if you have any doubts, treat your water to the best of your available ability.
ATB
Ogri the trog
I'd expect any chemical contamination from tarp coatings to be very minimal if any, the whole point of the coatings is to repel the water droplets so they're unlikely to be anything water soluble that's going to come off at reasonable temperatures.
However, as others have pointed out, it's worth thinking about where the waters been before it's hit the tarp and what's been on your tarp before you strung it up ( used as a groundsheet or left in the dirt? )
Probably a good idea to rinse of a new tarp but basically I'd treat it like I would rainwater that's fallen an gathered anywhere else around me unless I'd used the tarp for something else previously.
Having seen pictures I suspect yours might taste a little smokey though ;) Which makes me think there's more to worry about with natural enviroments factors here and what woods been used for fires nearby than tarp coating contamination.
william#
02-06-2007, 12:16
probably the best advice is too boil no matter what source you use (iodine can miss i think certain cist type organisms such as jardia).and chlorine tabs - yuck!
but water you get from tap is essentially rain water with a bit of filtering and chlorine - think fluoride is in our tap water too.
as for myself i would not worry too much about drinking tarp water but as in the uk i am pretty near a tap most of the time i could only see myself rarely using water from a tarp.
Of more concern would be the crap the rain water picks up in the atmosphere as it falls to earth. I was told once to collect water after five or ten minutes of rain as the pollutants are washed out of the air by then and the water will be OK to drink. Tarps would be washed out by this stage too, unless it is strung up under dense foliage. Boiling will, of course, concentrate any pollutants in the water by the fact that they stay whilst water vapour is driven off whilst boiling. Bear that in mind!
Snip> I was told once to collect water after five or ten minutes of rain as the pollutants are washed out of the air by then and the water will be OK to drink. Tarps would be washed out by this stage too, unless it is strung up under dense foliage. <snip
That's pretty sound advice.
As mentioned I have never worried about it but having posted a thread advocating such collection I thought it best to check my ground as it were.
Was the above advice given in the military? if so it could explain the original query...
To be honest, I cannot remember who told me that or if I read it in a book somewhere. I reckon it may have been in a book, maybe Wiseman or Graves.:dunno:
Ditch Monkey
04-06-2007, 13:45
I have a spare tarp that I put out when it starts to rain as my basha / house is located under a Yew tree for extra protection from the weather. I have collected water running off my roof on occasion but try to only use it for washing / cleaning as I worry that some of the toxins from the tree might contaminate the water. Doesanyone know how poisonous Yew is as often it is tempting to use this water rather than walk a couple of miles to get some fresh stuff?
I have a spare tarp that I put out when it starts to rain as my basha / house is located under a Yew tree for extra protection from the weather. I have collected water running off my roof on occasion but try to only use it for washing / cleaning as I worry that some of the toxins from the tree might contaminate the water. Doesanyone know how poisonous Yew is as often it is tempting to use this water rather than walk a couple of miles to get some fresh stuff?
The toxins in yew are not very water soluble at all, but you only need a very small amount of some of them to make you ill/die. I regularly drink from a well that is surrounded by yews, but I personally would not drink the rain water gathered from a tarp under a yew. I have found one case of a man that died from drinking a decoction of yew leaves so some the toxins must come out in water.
I will try and find some understandable sources on the internet.
Ditch Monkey
04-06-2007, 19:05
Death isn't that high on my to-do list. I think I'll make the effort to gather water elsewhere.
Thank's for the heads up.
Singeblister
05-06-2007, 00:17
I suppose it all depends on what you have near you , I would have no problem drinking rain water , unless I had a tap with in easy walking distance , If I had a fire going I would boil it , If I didn't I would probably just drink it if I was thirsty enough , but then I am not the safest person around ;)
For those interested in collecting tarp water I thought they might like to check this product out. It's a tarp tensioner/water collector
http://www.hennessyhammock.com/new-products.html#water
I don't like the idea of drinking it untreated, but with boiling...
They were the inspiration for this (http://www.bushcraftuk.com/forum/showthread.php?t=21899).
http://www.ravenlore.co.uk/assets/images/Water-collector-1.jpg
Ditch Monkey
05-06-2007, 10:33
I suppose it all depends on what you have near you , I would have no problem drinking rain water , unless I had a tap with in easy walking distance , If I had a fire going I would boil it , If I didn't I would probably just drink it if I was thirsty enough , but then I am not the safest person around ;)
I have a similar approach, been ill quite a few times.
John Fenna
05-06-2007, 11:25
Yea Gods - have you seen what is in the water that comes out of your taps?
I think that tarp water was to be a safer bet - even a tarp pitched under Yews next to a power station and lead works!
John
Ditch Monkey
05-06-2007, 11:33
Yea Gods - have you seen what is in the water that comes out of your taps?
I think that tarp water was to be a safer bet - even a tarp pitched under Yews next to a power station and lead works!
John
The trick, inasmuch as there is one, is to leave the tarp out in the rain to wash off for a while until the water runs clean, or to let the gunk settle and try not to think about it too much.
w00dsmoke
05-06-2007, 13:07
;) If anyone remmbers reading wilderness cabin living books...you'll remember that rain water and snow water needs to be oxygenated before drinking as it tastes very flat...apparently you are supposed to stir it up a bit or something before drinking to make it taste better?