How to Build a Very Effective
Water Filter System for Approximately $75
Copyright © February 10, 2010 by Robert Wayne Atkins, P.E.
All Rights Reserved.
An effective water filter system that will process about 10,000 gallons of drinking water can be made using:
- A replacement water filter cartridge such as the ones made by Berkefeld or Aquarain (about $50).
- A plastic food grade five or six-gallon pail or bucket (about $3).
- One or two heavy duty tarps (about $10 each).
- One or two heavy duty plastic tote containers (about $8 each).
- Some strong nylon or polypropylene cord or twine (about $4).
The first step is to capture rainwater using heavy-duty tarps.
You will need some strong nylon or polypropylene cord or twine to secure the grommets in the outside edges of a tarp to some nearby objects (such as some trees) so the tarp will hang down in a “U” or “V” shaped pattern from side to side and with the rear of the tarp about one-foot higher than the front of the tarp. Place a large clean empty plastic tote container at the front end of the tarp at the center of the “V” to catch the rainwater as it pours out the front end of the tarp.
As a practical example, if it rains one-inch and you have the tarp arranged in a “U” or “V” shape then:
1. A single 9-foot by 10-foot tarp will collect approximately 50 gallons of rainwater.
2. A single 10-foot by 12-foot tarp will collect approximately 70 gallons of rainwater.
For planning purposes you will need approximately one-gallon of water per day per person. This is enough water for drinking and for brushing your teeth. It is not enough for cooking, or bathing, or washing the dishes, or doing the laundry. These activities will require significantly more water.
You should have enough drinking water for each member of your household to last at least 30-days.
Rainwater is safe to drink if you can catch it before it comes in contact with anything else. In other words, if you stand outside with your mouth open and the rain falls straight down from a cloud in the sky into your mouth then you could swallow that water and not worry about getting sick (assuming the air was not full of smog or something else).
However, if the water makes contact with anything else, such as the leaves on a tree, then you will need to process that water before you drink it.
There are also several other factors that may force you to process your rainwater before you can drink it. Some examples would be:
- A limited nuclear war anywhere on the face of the earth. The tiny nuclear particles can travel extraordinary distances after they have entered the upper atmosphere.
- A volcanic explosion that pumps huge amounts of volcanic debris into the upper atmosphere.
- A small meteor that hits the earth and sends huge amounts of debris into the upper atmosphere.
If any of the above events occurs then it would not be safe to drink rainwater until after you have filtered it.
The simple inexpensive solution to the water filter problem would be to purchase one good quality gravity water filter. A good quality water filter will process about 10,000 to 12,000 gallons of water before it wears out if you pre-filter the water through a clean cloth before putting it through your water filter. One good water filter will provide about 7 or 8 gallons of drinking water each day.
The type of water filter I recommend is the “replacement” filter that you would install in a $250 to $350 gravity fed water filter system such as the British Berkefeld or the AquaRain. If money is not an issue then you could buy one of these complete systems. But if you need to be very careful about how you spend your money then all you really need is one replacement water filter for about $45. One water filter will process about 10,000 gallons of water at a rate of approximately 7 or 8 gallons per day.
When you order your water filter please be sure to specifically request that they ship the filter with a new “O” ring and a new “wing nut” for the bottom of the filter. With a new water filter, and an “O” ring seal, and a “wing nut” you can install your filter on anything that will hold at least one-gallon of water, and is also at least as tall as the filter itself. For example, you could install a water filter in a food grade 5 or 6 gallon plastic bucket, or a plastic tote container, or an empty one-gallon plastic water bottle (after you cut the top off the bottle). The container must have a flat bottom surface at the position where you will install the water filter. Simply drill a one-half inch diameter hole in the bottom center of the container and then put the “O” ring tight against the filter on the inside of the container and then screw the “wing nut” to the filter on the outside of the container. Then put the modified water filter container over another clean container that will catch the filtered water and fill the water filter container with water. Then relax and wait for gravity to move the water through your water filter into the lower container.
The lower container below your water filter container could be an ordinary water cooler with a normal water spout. These plastic water coolers are frequently sold in the camping section of stores. The advantage of one of these water coolers is that they have an airtight plastic lid that you can put on top of the water cooler after you remove your water filter container. This lid will help to keep the filtered water inside your water cooler clean. When you need some drinking water you could activate the bottom spout on the water cooler and clean water would flow out of the water cooler, through the spout, and into your drinking glass.
If you are filtering out radioactive particles then position your water filter system far enough away from your living quarters so the tiny radioactive particles that will get trapped inside the water filter cannot slowly poison your family members. Radiation only kills living organisms. It does not kill non-living things such as water or canned food. However, if you ingest water or food that contains radioactive particles then you will get sick and eventually die. However, if you remove the radioactive particles from the water then the water will be safe to drink. In other words, after you have removed the radioactive particles from the water then the water could be brought into your home but the water filter that trapped the radioactive particles should not be brought into your home.
One cheap way to store a lot of water is to use 5-gallon food grade plastic buckets or clean empty large heavy-duty plastic tote containers. Please remember that water is very heavy so please don’t try to move a heavy plastic tote full of water. You could easily injure your spinal column. If you must move the water then move it a few gallons at a time by transferring it with cook pots to the new location.
Or you could store your extra water in clean empty two-liter soft drink plastic bottles with screw on caps. Or you could refill empty plastic water bottles that you saved for this purpose. These would be the 16-ounce to 20-ounce clear plastic water bottles that are sold by the case.
One quick final comment about water: your body needs water in order to digest food. Therefore if you don’t have any water then don’t eat.