AS A medical student in Glasgow in the 1960s, I began to appreciate water. The city’s supply came from Lake Katrine, pure, undefiled and with a clean taste, whereas the effluent emerging from the taps of Paris, London and the Rhine Valley where I hitchhiked every summer left white residues and malodorous whiffs on both faces and glasses – hence a fluid shift to vin ordinaire, tepid bitter beer and a continuous Oktoberfest.

No one in this part of Africa is indifferent about water, whether for drinking, washing, growing crops, as flooding or a prolonged drought. Our own source of potable water is from a borehole on the farm, the nearest piped system being over 70 kilometres away. Most folk drink from gaily coloured plastic bottles which are not cheap but unavoidable, like Google, cellphones and taxes – and like them, the small unit costs mount over time.

Research in Kenya showed that if these same bottles were filled with untreated river water and exposed to 6 hours of direct sunshine, the irradiation killed off almost all bacteria, viruses and parasites and could be safely drunk. I explained this to my family and neighbours, brandishing a copy of the research paper, and emphasised the economics – the saving of 20p per bottle interested everyone – before going into production, thirty bottles a day laid in rows in the blistering heat. After two weeks, no one was drinking it except myself. I had not realised that going to the village to buy the damn stuff was a social occasion where you met friends, that its purchase showed economic muscle (even if it was your parent’s money), and that the attractive labels and smart-ass adverts had a cachet which my unadorned and somewhat battered bottles did not.

Raw water is murky, may harbour typhoid and bilharzia if sucked up from a river’s pools and not the main stream, and is expensive. Ours is delivered by a huge tanker which has knocked down part of the farm’s main entrance gate and crushed a line of sweet potatoes in the crew’s haste to fill up our four containers on top of their steel towers, extract a small fortune for the visit, then hasten to the nearest shebeen for a Nile Special beer.

Flash floods are not rare, the walls of water being generated in the high mountains on the South Sudan border. Last year, folk up-country were able to phone and warn those 50 kilometres away but most of the traders in a huge local market ignored the calls. By dawn next day, only the tin roofs of their shops were visible above the muddy flood, the wood and grass stalls long swept away – and probably still on the way to Cairo as I write this a year later.

At least they were not in the Sahara. Some time ago we were staying in Haj Yussuf, a non-Muslim suburb of Khartoum, and witnessed the effect of super-saturation on desert sand after weeks of rain. Thousands of domestic pit latrines caved in, one consequence being that natural bodily functions were now limited by modesty to night-time, there being no street lights in Haj Yussuf. About midnight,we crept out in desperate need of relief, toilet rolls under arm. Rounding a dark corner and switching on the torch – lo! there were many of our neighbours, squatting in a row beside a wall. The torch switched off and privacy restored, it turned into a mild celebration with wry comments and amusing observations in several languages. I did wonder what the reaction of my mother and her friends in Glasgow’s genteel Kelvinside would have been had they suffered similar supersaturation.

Dr David Vost studied medicine at Glasgow University and is currently working at a hospital in Swaziland. He and his family live on a small farm in Northern Uganda near the Albert Nile. davidvostsz@gmail.com

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