Lightweight Backpacking Part Two: Water Filters
Beaver Fever and Water Filters
If you think to be in a remote wilderness area means that the water you find out there is safe to drink . . . then think again! There are so many pollutants and pathogens floating around in our lakes and stream that the days of dipping your cup directly into the water for a drink are long gone.
One of the worst bugs to pick up is Giardia Lamblia. The tiny cyst gets into the water cycle by being deposited with the feces of an infected animal. The usual host is the beaver, which is how this water born pathogen got its nickname “beaver fever.” But it can be deposited by any mammal, including humans.
It only takes ten Giardia cysts to infect your body. The microscopic protozoan, measuring 21 microns in length (the tip of a sewing needle measures 700 microns), hatches inside the small intestine with an incubation period from five days to several months, reproduces like wildfire, establishes a colony, and then has a little party in your gut -making you feel as if Montezuma has moved north to seek his revenge.
Symptoms can be severe or completely unnoticeable. They include: diarrhea, abdominal cramps, fatigue, weight loss, flatulence, and nausea – not a pleasant experience while being away from flush toilets and a local pharmacy. Usually, however, you get it when at home and then just assume it’s the flue. However, if the cyst does not get treated, it can cause severe problems. I’ve been affected three times and each case took over a month to treat with antibiotics.
The best purification system for drinking water is a filter. You just pump and drink. And by making water collection so quick and easy there’s less chance of becoming dehydrated.
There are a few disadvantages, starting with the high cost. The main body of the system itself is not that bad. But the price of the replacement filter is outrageous. If you only go on a one week trip per year then the filter should last you a couple of years. But if you’re out all season you’re going to use up at least one or two filters, each which cost close to $40 each. The only way to save money is to always wash the filter out after each trip. It’s also a great idea to wrap a coffee filter around it to help extend the use.
Filters strain out microscopic contaminants like Giardia but they don’t necessarily eliminate bacteria or viruses. The purity of the water greatly relies on the size of the filter’s pores. Any pore-size of two microns or smaller will get rid of nasty pathogens like Giardia and surface pollutants. However, it takes a pore size of less than 0.4 microns to remove bacteria, and viruses