A foundational assumption to our borehole repair and drilling program is that groundwater from a borehole is healthier and safer than water from a spring. Any hydrogeologist as or humanitarian worker in the WASH (water, sanitation, and health) sector is taught that the ground surface, and clays in particular, protect against the infiltration of animal and human waste into groundwater, and that the earth acts as a filter, removing toxic contaminants along the groundwater flow path, including dangerous bacteria.
But is this really true? Is that crystal clear African stream less safe than that rusty old hand pump where cows, goats, and chickens are gathered? Is that spring flowing from a hillside actually more of a threat to human health than a handpump where women are collecting water, washing clothes, and cleaning pots?
In the past, I always simply accepted that in rural Africa, groundwater is good, surface water is bad. After almost every talk I have given, the question is raised “did you test for bacteria”? My answer is always a “no.” No incubator. No electricity. Difficult to transport chemicals. Unreasonably strict hygiene requirements for handling samples in the field. It simply was not possible.
In this Uganda campaign, though, largely at the urging of IsraAID's Selda Edris and BGC’s geochemist Kate Robey, we used a relatively new test kit developed by Aquagenx that requires no incubation, no electricity, no difficult-to-transport chemicals, and is relatively simple to implement. At each handpump repair site, including a few of our repair sites from our 2018 Geoscientists Without Borders program, we have tested the water for E. coli.
Meanwhile, at all of the exploration sites where villages lack a water well and are reliant entirely on springs or rivers, I have collected surface water samples also for E. coli testing. I always do this myself as I get the chance to see the area beyond the immediate village, I can pick up a bit of Acholi language from the parade of villagers that always accompany me, and I get a better sense of the level of effort people expend to gather water when they have no village handpump.
The results and conclusions have been clear and consistent. Of the 11 handpumps we sampled for E. Coli, all were within safe limits of between 0 and 4 CFU (Colony Forming Units). This even included 2 handpumps we installed in 2018 and 2 we repaired in 2018.
In comparison, I sampled 9 springs, each of which was serving as the main water source for a community. All of the springs had high to extremely high CFU counts, with 4 of the springs having counts greater than 100 CFU. Most of these water spring-dependent communities complained of diarrhea, typhoid, and cholera.
As bucolic and sleepy as bacteria counting, water spring sampling, and geophysical surveys may seem, field work has its moments. Yesterday, near the village of Agikanyi, hunters set fire to the forest to drive out the small mammals. The forest erupted into multiple walls of flames towering above the trees, first moving away from our survey and sampling area, and then, with a shift in the wind, moving directly toward the village spring, our crew, and the village.
I was watching the smoke, sitting in the village drinking tea and eating my first Acholi donut of the morning while contemplating my second. I was listening to the somewhat panicky chatter on the radio about the flames jumping the valley – but people can run. But I then heard that the flames were within 20 m of the cables, and I was running as fast as I could downhill, donut in one hand and camera in the other. Cables cannot run, and can only be pulled.
A photo of the normally unshakeable Serena showing a bit of concern is posted.