Water Sources in Africa and particularly in Uganda are;
1. Clear flowing water and
2. Lakes, ponds and rivers
Clear flowing water coming from somewhere without people, manmade things or an obvious sign of pollution is best.
Lakes, ponds and rivers are less ideal. The first two are stagnant, which may mean increased levels of bacteria and other gross things, while large rivers are typically full of pollution. Not forgetting that any flooding or if the river flows from or through a population center, under a road or around any construction, chemical plants or similar on its way to you.
Filtering: There are a million filters on the market, but they all fall into two categories — one's equipped with carbon or ceramic filters that remove gross stuff and bacteria or ones that also treat the water with iodine or another chemical to kill viruses. Filters are complicated, heavy expensive and need to be replaced often. For that reason, I will not bother with them.
You can filter water from mud or dig for it in dry river beds or other low lying areas. One will require to dig a beach well or swamp well by digging a hole and shoring it up a ways back from the shoreline. Basically, there tend to be acceptably clean water underground around bodies of water or where they sometimes are.
Consequently it is usually cheaper and more sustainable for communities to prevent pollution and preserve the quality of their water resources than it is to treat polluted water. For example a community can fence off the catchment area of a small upland stream or spring to keep animals and children away from the site or keep the area clear of decaying vegetable matter to reduce potential taste problems and coloration. Alternatively the water from the source would have to be settled or put through a sedimentation process using a chemical coagulant and subsequently filtered and disinfected. The energy and chemicals required would be beyond the financial capacity of poor communities to procure them. Whereas the simple water quality conservation activities would be very easily achieved at little or no cost, although the community would have to devote their time to the tasks.
The exceptions to the foregoing are one or two instances where slow sand filtration is adopted when there is no alternative to a surface water source such as a river, stream, lake or pond being used as no alternative is feasible, other than perhaps rainwater harvesting.
Any source that is highly turbid with high suspended solids must be filtered before disinfection with chlorine etc. This is because particulate matter left in suspension may contain encapsulated pathogens that if chlorinated would escape oxidation. Subsequently this encapsulation could break down when ingested and carried into the gut of the drinker and thereby infecting that person.