Ever wondered what lurks in untreated water? Gordon Deadman from Bushcraft Survival Australia gives us the low-down from an emergency and survival perspective   


Summer. It’s the time for sunscreen, the smell of sausages on the BBQ and the sound of waves crashing on the sand. It’s also the time when keeping hydrated is the most crucial while you’re camping, and most definitely in a survival situation. The thing is, most of us tend to get a little bit relaxed when it comes to topping up our water storage. Weather it’s filling up the camper trailers tank from a freshwater stream or re-filling up our water bottles from a National Park rainwater tank there are most definitely risks involved. With that in mind, let’s take a closer look at what can lurk in untreated water. 


If you are reasonably hydrated, you should be producing at least 1 litre of clear to straw coloured urine per day. The more dehydrated you are, the darker the urine colour and the output less.

Thirst is not a good indicator of dehydration. By the time you are thirsty, you are already dehydrated so drink before you get thirsty.


  • Thirst
  • Headaches
  • Dizziness
  • Tingling in limbs
  • Irritability
  • Reduced urine
  • Saliva output
  • Dark urine
  • Poor decision making
  • Muscular aches and pains
  • Nausea 

If these symptoms are left unchecked, they can further deteriorate and lead to heat exhaustion, then turn into heat stroke which is a life-threatening condition.


We’ve all herd to make sure your water is safe to drink, but what is it that actually makes it unsafe to ingest? Well, here are the 5 main contaminants that you need to know about!


This is the measure of relative clarity of a liquid. Cloudy, hazy or muddy suspended particulate matter such as sand mud, silt or other decomposing organic material must be removed first through filtering for all water purification methods to be able to work. Even if there are no pathogenic (disease causing) organisms in the water, turbid water can still irritate your stomach.


These are microscopic organisms that live on or in another host organism. They can be either single cell organisms such as protozoa and cysts or multicellular organisms such as worms. Protozoa are parasitic or free-living organisms that are able to multiply in humans and other animals causing disease. Eg. Cryptosporidium and Giardia.


Much smaller than parasites, bacteria are single celled organisms found almost everywhere on. Some bacteria cause disease while others don’t. The ones that do, produce a wide range of infections, some of which are potentially lethal.


A virus is a sub-microscopic infectious agent (not a cell) that replicates only inside the living cells of an organism. Still smaller than bacteria, viruses infect all types of life forms including animals, plants and other microorganisms like Hepatitis A, Polio, Traveller’s Diarrhoea and viruses in the water from poor sanitation.


Pesticides and heavy metals from man-made polluting sources such as mining and agriculture.


Coarse filtration using a Milbank bag/Brown Bag, bandana or piece of thick cloth removes turbidity and sediment and is the first stage in treatment for all methods. It can reduce the load of pathogenic organisms if they’re attached to dirt and the like. However, it does not filter out even the largest pathogenic organisms directly. Coarse filtration is needed to make water clear so that chemical methods work more efficiently.


This uses a ceramic filter. Pump or gravity system to remove larger pathogenic organisms. 


Activated carbon filters are the only way of getting rid of most chemically polluted water. They remove pesticides, herbicides and many other toxic chemicals such as dioxin, benzene and styrene but it does not remove all chemicals or smaller pathogenic organisms. Activated carbon also removes tannins and phenols which improves taste and smell. 


Boiling water is the simplest and most reliable way of making water safe to drink. It will kill all pathogenic organisms but does not remove chemicals. A rolling boil for 1 minute at sea level is all that is needed to make water safe to drink. Water boils at a lower temperature the higher you go in elevation so boil for an extra minute for every 2000ft. 


Water is so crucial to the human body, so it kind of makes sense to get a good understanding on how to ensure it is safe to drink. This knowledge can be applied in a survival situation as well as for general maintenance on your camper trailers’ water system.