I picked up a Sterri-pen last fall when they were on sale at Costco. Haven't tried it out yet, but the reviews are mostly good. I think it is going to be a little easier to operate, runs on AA cells (so potentially solar powered), and for where I live should work.
.........I'm fairly paranoid about drinking water, so I might just do both as a belt and suspenders fix. I've heard that filters can actually make things worse becoming a breeding ground for microbes if you're not careful (which I'm not

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This is a good tip. I took a look at the Sterri-pen, and I agree it cannot hurt to treat filtered water a second time. Also, I started looking at carbon filters as the last step to remove odors, and some chemicals. So, to use your analogy, belt, suspenders and clean underwear. Using the Katadyne, then the Sterri-pen, then a carbon filter. It is also possible to chemically treat water or boil it, but those methods need supplies that can be limited. I am also looking into a solar still to distill water, probably the cleanest you can ever get it. I do not see anything interesting yet. But the price of the Sterri-pen and carbon filters is reasonable.
Linking this all back to Ecomm, I do not know why the amateur radio Ecomm emphasis is on teaming up with first responders and government. While that is important, every neighborhood needs ordinary communication during a crisis. My "prepping" emphasis is on survival in my own home without outside support, and I would extend that to my neighbors, at least the communication component. I would have zero problem communicating from my home for an indefinite amount of time, in an emergency, passing messages and email to others and so on. Due to the hostility between some HOAs and ham radio, bringing Ecomm to the level of helping your neighbor, and letting the HOA organize the effort may lower the hostility. I hesitate to go tell them who I am, BUT I would not worry if my local ham radio club approached them, made the contact and arrangements, and then revealed my identity as the provider at the last possible moment in an emergency so that I can keep my anonymity and hidden antennas hidden.
I will be sipping nice clean cool water when they come knocking at my door. I might even offer them a sip if they are nice to me.
Rene - WA6MJE