Everyone knows that one of the most important necessities of human life is water. Yet when one of the one is out in the field next addition or out of the Bush or even just a short weekend camping trip, it can be difficult to get clean water that is safe to drink. In some places such as India or parts of South America, there is a real risk of catching waterborne disease from drinking untreated water. This water may contain viruses, it may contain bacteria and it may contain protozoa and internal parasites. At best you might just get a few days of diarrhea, at worst you could contract a serious illness such as cholera that is genuinely life-threatening and can kill you in a couple of days.
So when I’m out in the field I always make sure I have a good source of clean water. There are a couple of approaches to cleaning water. The first is boiling it. The advantage of this is that you don’t need very much equipment apart from a fire, a pot and a bit of time. Water that has been boiled for about 10 minutes is completely safe to drink. In that time as long as the temperature is high enough, you can be sure that you can kill all the viruses all of the bacteria and any other internal parasites or protozoa such as Giardia that might be in the water. The problem with boiling water is that it does take some time. If you don’t boil the water long enough you can’t be sure that you have killed everything that is in it. You also need to remember to boil water for a longer period if you’re at altitude. This is because the higher you are at the lower the boiling temperature of water becomes. So you need to boil water the longer to kill everything that is in it.
The second downside of using boiling is your main method of sterilization, is that requires you to carry enough fuel if you are using a stove and of course requires that you stop and set things up to get your clean water. You can’t just grab some water from a stream as you go, which is why I prefer using other methods such as chlorine or iodine. Water sterilization by chemical means is both quicker and a lot easier that boiling water. When it comes to chemical methods there are two main chemicals that you can use to clean your water. The first is chlorine. The second is iodine. Both work pretty well and have a long history of use and both have their advantages and disadvantages. The advantage of chlorine is that it’s used regularly and has been used in many parts of the world in municipal water soppy. It’s convenient in that you only have to add a couple of pills to your water bottle and wait a little bit of time. The downside of chlorine is that it is not as good as killing some of the tougher bugs that are out there. Things such as Giardia are either not killed by chlorine or you have to sterilize water for a long time to be sure of getting rid of them. This is where iodine comes in. Iodine is better at killing some of the tougher organisms out there. The disadvantage of iodine is that you don’t want to be using it for too long. The reason for that is that long-term consumption of iodine can be bad for you. A second disadvantage of iodine is that so makes the water taste unpleasant.
Of the two methods of chemical sterilization I have generally is used iodine when going out into areas where I think there is a high risk of infection. In Nepal, for instance, I routinely used iodine to keep my water clean. The reason I did this is because it is stronger. We however, when just hiking out of the normal backwards, the water itself may already be pretty clean if it comes from a running stream, I just using chlorine tablets to be sure. Both of these methods of cheap may only cost a couple of pennies a liter, and they’re pretty convenient. You either just has to add a few polls usually one book per liter, or a few drops of iodine from a dropper, to your water bottle. You then have to wait long enough the chemicals to do its job. How long you have to wait depends partly on the temperature, colder water takes longer to clean, as well as the sorts of bugs you’re worried about. If you’re concerned about things like Giardia, that have to kill, then try to get at least 30 minutes sometimes longer.
The other main method of cleaning water is filtration. Filtration is based on the simple principle of using some sort of filter, usually a ceramic but sometimes something made of carbon, to trap bacteria dirt and bugs and to only allow clean and pure water through the filter. The advantages of camping filters compared to other to processes are that you can clean large quantities of water over time and that you don’t have very many ongoing running costs. You also don’t need to carry a resupply of chemicals with you. And they allow you to take muddy or unclear water that might be otherwise unpleasant and you can filter it into pure clean drinking water. The disadvantages of camping filters are the costs and the weight. A small bottle of iodine or chlorine costs just pennies whereas a filter can easily set you back more than $100.
That said the cost and weight of portable water filters has come down considerably in recent years. These days, you can even get a simple straws and attachments to your water bladder that will filter water quite effectively. So the balance between the costs of chemicals vs. the convenience a small water filter is now much more even than it used to be.
But there is that there are some things to keep in mind around water filters. The first is that many water filters are unable to prevent viruses from passing through them. In that case you may still need to add some sort of chemicals such as chlorine or iodine to your water to be sure of killing dangerous viruses such as hepatitis. Just keeping the dirt and that churns out is not enough. You can also get portable forces with built-in virus protection. These are more expensive but a safer option.
Still, to my mind it is hard to beat the security of chemicals in really dangerous places. Having managed to stay pretty safe in many parts of Africa and in Nepal and India using chlorine pills or iodine drops, I would generally recommend them. One of the main reasons I like them is that they also sterilize your water container. On the other hand, if you only use a filter and just one drop of dirty water splashes into you water container it will quickly contaminate all of the water. So when I’m in dangerous places I make sure to sterilize my water, even after I have filtered it. But on normal weekend trips in the backwoods I’m quite happy to just filter my water.