Simple $30 Pumped Water Filter

Filter and pump

I do a lot of outdoor activities like cross-country hiking, kayaking, etc. In the past I have tried many methods for filtering water. It’s easy to spend a lot of money and get not very good results. One product that has always intrigued and frustrated me is the Sawyer filter.

Sawyer Filter With Bags

This is a great filter except for two really frustrating things about it. You can screw it onto a bottle and use it like a lifestraw, but that’s not ideal because you need to clear it every time you use it, so it’s really not designed for sipping all day.

Their solution is these squeeze bags. Basically you fill the bag with river water and then screw it onto the filter, and squeeze the bag to push the water through the filter so you can get clean water in your camelback or nalgene. The big theoretical benefit here is that you don’t have to carry dirty water with you.

The problem is that the squeeze bags are really hard to fill since they want to go flat in the water and not let any water in. So basically while these seem great, I’ve always found them very frustrating. I tried these years ago before buying the lifestraw bottle instead.

 

Enter the Lifestraw Go Bottle. Kind of great, kind of not.

Lifestraw Go Bottle

So here you can see the Lifestraw Go Bottle attached to my kayak. It’s great for kayaking. You can just quickly fill it and then sip throughout the day. The filter is designed to work that way. You only have to clear it when it starts getting hard to suck water through the straw, maybe just a couple times a day depending on the water.

The problem here is that it’s a tiny bottle, just 650ml. So you can’t carry more water than that. This makes is basically useless for hiking unless you’re hiking along a river. There is no way to get clean water into another container with this filter.

 

My Idea…

I have worked with lots of small electric pumps on other projects. In the past I have wondered about using one of these little pumps to push water through the Sawyer filter so I picked one up to test out. This would mean basically you can fill up all your nalgenes and camelbacks and other containers and have as much water as you want, very easily and quickly.

Filter and pumpThis tiny electric pump fits perfectly in the straw the Sawyer comes with, and works at almost full speed; about a gallon per minute. There is also a USB version of this pump which should work just fine. The USB version also includes a coarse filter to keep debris out of the pump which should improve the lifespan.

As you can see, this is tiny, weighs almost nothing, and cost just about $30 all together. You probably have some kind of battery bank or solar panel you’re already taking with you, so you can put together whatever version of this that will run off your existing setup, USB or 12v.

I will be testing this out in the coming days and I’ll report back on how it works in the wild.