DIY Gravity Water Filter

Trapper

Author, Writer, Photographer
#1
When you need filtered drinking water for 12 - 20 people you figure out really soon that pumping by hand doesn't work well.

I built this after seeing something similar and then doing some research and a few trips to the hardware store.


It's gravity feed. A collapsible 5-gallon cube with a spigot pulled up into a tree with the use of a pulley and rope. Five gallons weighs 40 lbs. No big deal but trying to pull a rope over tree bark adds enough friction that a pulley was in order.


I use a 2-stage filter. Stage one is a sediment filter - 50 microns. Stage Two is a .2 micron charcoal filter. Most water guys are saying .5 micron will filter out most giardia. The filters are connected with a simple plastic pipe thread with two male ends. I have a surgical tubing to pipe fitting adapter on the Input side. I have a coupler and on/off valve with a pipe fitting to tubing adapter on the output side. I'm using 3/8" ID tubing.

The water then flows into a 5-gallon water cooler with spigot. My first test filtered the entire 5 gallons in just under 10 minutes.

 

Trapper

Author, Writer, Photographer
#5
The problems I've had with some commercial filters are:
1. The ones you pump are slow and a pain in the ass for filtering ~15 - 25 gallons/day.
2. The gravity filters all have specialized single filters you can only buy at certain stores and they clog easily and cost in the $50/range.
3. They are designed for backpacking so they sacrifice size and weight for volume and filter cost.
 

Jerry Daschofsky

Moderator
Staff member
#7
I'll ask my brother in law what they were doing. They had to make a multistage gravity filter system in Afghanistan. Had to be cleaned daily. Just by time they got in country they used air drops with supplies and water mostly over the filter system. But way he described it, sounded pretty easy.