Volume for a household against weight for a pack.
Verdict
A gravity system filters many litres unattended, which is what a household needs. A squeeze filter weighs a couple of ounces and fits a pocket, which is what a pack needs. They are not competing products so much as answers to different questions. Buy the gravity system for the house; buy the squeeze filter for the bag, and ideally own both.
| Big Berkey Gravity System | Sawyer Squeeze | |
|---|---|---|
| Throughput | Litres per hour, unattended | A litre at a time, by hand |
| Weight | Heavy countertop unit | About 3 oz |
| Filter life | Very long | Long, with backflushing |
| Power needed | None, gravity | None, hand pressure |
| Best for | Home, shelter in place | Bug-out bag, hiking |
| Cost | High | Low |
You are planning to stay put. A family needs several litres a day for drinking and cooking alone, and hand-squeezing that volume every day gets old immediately. A gravity unit fills itself while you do something else.
Check Big Berkey Gravity System on Amazon
You may have to leave, or you want a filter in every pack and vehicle. At three ounces and forty dollars there is no reason not to own several, and it removes bacteria and protozoa effectively.
Check Sawyer Squeeze on Amazon
Most hollow-fibre filters, including squeeze filters, remove bacteria and protozoa but not viruses. In North America the practical risk from wild water is bacteria and protozoa, but for questionable municipal supply or floodwater, add chemical treatment or boiling.
Hollow-fibre filters do not remove most dissolved chemicals. Gravity systems that use carbon-based elements address taste, chlorine and some contaminants. Neither should be relied on for water contaminated by industrial chemicals or fuel.
One gallon per person per day is the common planning figure, covering drinking and basic hygiene, and two weeks is a sensible target. A filter extends your supply but does not replace stored water, because you may have nothing to filter.
Comparison based on published manufacturer specifications and the general consensus of owner reports. We have not tested these units side by side. Confirm current prices and specifications before buying. As an Amazon Associate we earn from qualifying purchases, at no extra cost to you.
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For informational purposes only. Follow guidance from FEMA and local authorities.