You can get water purification tabs in many places on the net. They make the water taste terrible and don’t have a super long shelf life. I’d recommend a filter system. If you have the cash a Berkeley Water filter is good. They aren’t something you can pack but work great in the home or camp for anything except viruses. A portable filter is on my list as well.
You can also build your own filter. Lots of good info here http://www.survivaltopics.com/survival/water/
Don’t rule out rain barrels either.
I answered Possum up there before seeing your comment. I’ve had a Berkefeld for 11 years and wish I could buy a back up just in case. I do have a couple of spare filters. They make good tasting water.
water filter bump