For the most part we maintain our water supply by filling up from tap water available at gas stations, grocery stores and, if need be, asking home owners, but when the availability of tap water becomes more sparse we have a two stage water filtration system that can be used to filter water from creeks, rivers or ponds.
The first stage in our filtration system is the LifeStraw Family 1.0 water filter. This filter boasts a 0.02 micron filter allowing it to filter out over 99% of bacteria, protozoa and viruses. The manufacturer claims this filter will last for 18,000 liters of water giving it a very low costs per liter and, particularly for just the two of us, a long lifespan.
The LifeStraw is not maintenance free, the filter will need to be back flowed periodically and the frequency of this will depend on the quality of the water you're filtering. The instructions say back flowing the filter is done by pumping the red ball pump on the filter and letting it fill three times, but in practice this sometimes needs to be repeated several times before water starts flowing through the filter again.
Our second stage is an old spent ZeroWater filter, we pried off the screen from the top of the filter then dumped out half the contents and replaced it with new activated carbon of the coal variety. This should remove a number of toxins from the water and, apparently, improve the taste. It should be noted that activated carbon, or activated charcoal, is known for it's ability to filter out biological toxins, but apparently doesn't do so well with chemical toxins.
So far we've used this to filter water from a pond in a dried creek bed, two small road side creeks, one large creek and restroom water from a city park. The water always came out clear and tasting great. One exception earlier in our trip came after filtering from a creek running through a residential area. The water turned out perfectly clear, but had a strong fishy taste to it and any water we filtered afterwards also had this fishy taste. We were able to remedy the issue by removing the activated carbon, washing the filter housing with soap and fresh water then adding new activated carbon.
We use the 10 liter MSR Dromedary for our water reservoir. When looking for a water storage unit there were plenty of cheap foldable solutions available on Amazon, none of which looked as though they'd last a week. The MSR Dromedary is on the pricey side, but after heavy use I can say the money was well spent. The Dromedary is made of puncture resistant nylon, the inner surface of which has a water proof coating. Obviously the cap can be removed to fill the reservoir, but the cap also has a smaller cap that can be used as a pour spout when removed and that cap has a popup drink spout which comes in handy, not just for drinking, but controlled pouring.
We often hang the Dromedary from tree branches or the handlebars of our bikes, but even just laying on the ground it's not hard to move water from it to a bottle or pot. The puncture resistance is where the Dromedary really shines though, we've certainly had this thing on all sorts of outdoor surfaces and keep it strapped to one of our rear racks with bungee cords while riding and so far there has been not one leak. The cap stays on tight and the pouch remains strong.