Water filter for raw water

[EveryDayStubby]

I am trying to decide on a simple gravity water filter for pond and stream water. My concern is not chemical contamination but rather biological components. My father and I share adjoining lots, which have 4 ponds and a stream that runs through them. Upstream is a beaver den in a backed up valley. Many years ago, I got giardia and that was very much not fun. State came and tested the wells which were clean. My only guess is that my dog was swimming in the creek, I pet the dog and then ate some berries off of a berry bush.

Either way. While I recognize that boiling and chemicals are the best solutions, many gravity fed water filters make claims that they filter out biological components from the water and I was wondering if anyone has any experience in this area.

One example is the https://www.epicwaterfilters.com/products/epic-pure-water-filter-dispenser which I have read performed well with pond water but all of their certified testing is focused on chemical pollutants. Others say Berkey filters will, but they do not provide any certified testing results.

 

[justinotherguy]

We have an awesome and deep well that provides us with great water and backup power to keep it pumping BUT I wanted some redundancy. Since I have 2 lakes close by and a stream, I wanted a gravity feed water filter for rain water or the lake or stream water.

Birky seems like the most popular but I dont like to buy what I can make so by using 2 food grade 5 gal buckets and two ceramic filters, I made my own gravity feed filter. I bought a bunch of these and made a disposable fabric sleeve to trap particulate from lake water (it serves as a pre filter.)

two of these will sit in the upper bucket.

Culligan gravity water filter with MaxClear Technology

MaxClear Replacement Water Filter delivers fresh, clean-tasting water by reducing impurities. Compatible with MaxClear systems. Easy to install.

shop.culligan.com

 

[Spenser]

I took a 2 week water filtration course paid by the company I was being hired at. I was introduced to Reverse Osmosis water filtrations systems with built in UV light. A decade later while I was looking to buy a vacation home aka a log cabin in upstate NY, one of the cabins there I was looking at had almost the exact same system as I was being taught. There is no other water filtration system that I would trust for biological contamination than getting a Reverse Osmosis system with UV lights.

 

[GeoBoy]

Take a look at britishwaterfilter.com they are the original Berkey water filter company.

 

[justinotherguy]

I took a 2 week water filtration course paid by the company I was being hired at. I was introduced to Reverse Osmosis water filtrations systems with built in UV light. A decade later while I was looking to buy a vacation home aka a log cabin in upstate NY, one of the cabins there I was looking at had almost the exact same system as I was being taught. There is no other water filtration system that I would trust for biological contamination than getting a Reverse Osmosis system with UV lights.

estimated price for such a system?

 

[Spenser]

@justinotherguy the one I was working with was about $500 around 2 decades ago. These systems vary in price from manufacturer, and how long the filters are rated for.

You could buy a basic version for around $275, and the price only goes up depending on how much water you & your family would use on a daily basis. Other things to consider is how fast the flow of filtered water is. The more expensive units will have a much faster flow of filtered water, so you are not there twiddling your fingers/counting sheep while you wait for a glass of filtered water.

There are over and under the counter versions, ones with a tank reservoir and those without tanks. The price you pay will be determined by size, with or without tank, above or under counter, filter's lifespan, and flow rate for the filtered water.

You can check Amazon for a variety of different brands and sizes, etc. The larger longer lasting filters with tank can run around $800 for a large family. Another factor is how much the replacement filters will cost you.

I will say this, I was rather impressed when we poured a few gallons of vinegar through it and it tasted like water after it ran through the system.

 

[A Seedy Lot]

I would say if you are susceptible to giardia you should get a legit system to treat your drinking water.

You can set up a gravity systems to filter drinking water through a number of cheaper backpacking style water filters like Sawyers.

 

[Someguy]

TLDR: I suggest the OP use a gravity filter with a 0.2 micron cartridge to remove bacteria and protozoa (including Cryptosporidium).

With water treatment it all depends on what you are trying to remove/kill/render harmless. The OP mentions that biologicals rather that chemicals is what they are worried about.

As a general rule of thumb, biologicals in drinking water context are bacteria, viruses, and protozoa (including Cryptosporidium). As the OP mentions boiling and distillation will handle all of these.

Gravity filtration with a < 0.2 micron filter will remove bacteria and protozoa (including Cryptosporidium) but will not typically remove viruses. Removing viruses from drinking water is usually not a concern in the US (at least in the wilderness context), unless you are downstream from a very large number of people with nonexistent sewage treatment. In other countries removing viruses from drinking water IS a concern.

Most of the chlorine and iodine treatments like potable aqua and aquatabs (again wilderness context) are effective against bacteria, viruses, and protozoa but not against Cryptosporidium. The Micropur chlorine dioxide tablets claim they are effective against Cryptosporidium but need 4 hour contact time.

UV treatment is effective against bacteria, viruses, and protozoa (including Cryptosporidium) but isn't a gravity filter like the OP wants.

Reverse osmosis is also effective against bacteria, viruses, and protozoa (including Cryptosporidium) because it has a smaller pore size than the 0.2 micron filters but isn't usually available as a gravity filter. Reverse Osmosis filters are around 0.001 micron pore size.

 

[Someguy]

Source:
Wilderness Medical Society Clinical Practice Guidelines on Water Treatment for Wilderness, International Travel, and Austere Situations. H. Backer et. al. Wilderness & Environ. Med. 2024, 35, 45S-66S.

www.fema.gov/pdf/library/f&web.pdf