It is clear that we use too much plastic in general, that often ends up in oceans.

At home, we have tried to reduce by a significant amount our plastic consumption. Acting on the bottles of water was one item in our list. We have hence replaced single-used plastic water bottles by metallic re-usable bottles that we fill with (filtered) tap water. Of course, we live in a place were tap water is drinkable. This additionally solves the storage issue that you discussed in this post: plastic and sun are never good when taken together. We hence avoid the need to store dozens of bottles in a dark room.

In principle you could setup something similar in Nigeria, couldn't you? I remember recent blogs by @gentleshaid discussing wells that should make water easily available.