New UPGro paper: Better map-making for manual drilling in West Africa

In a new open paper in the Hydrogeological Journal, Dr Fabio Fussi and his UPGro Catalyst team present work done in Senegal that looks at how improving hydrogeological data, maps and understanding can improve the success of manually drilled boreholes.

In a region where access to safe, affordable water is limited, manual drilling provides a cost-effective way of tapping groundwater resources. However, aquifers are complex and striking fresh water is not guaranteed.

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Manual drilling in Lagos, Nigeria (photo: Dotun Adekile, 2014)

Fussi and his team propose a model that uses analysis of borehole logs for the to characterise shallow aquifers  so that areas suitable for manual drilling can be found. The model is based on available borehole-log parameters: depth to hard rock, depth to water, thickness of laterite (a iron-rich rock type common in the tropics) and hydraulic properties of the shallow aquifer. The model was applied to a study area in northwestern Senegal.

The hydraulic conductivity values – how easily water flows through rock –  were estimated from geological data and  partially validated by comparing them with measured values from a series of pumping tests carried out in large-diameter wells.

The results show that this method is able to produce a reliable interpretation of the shallow hydrogeological context using information generally available in the region.

The research contributes to improving the identification of areas where conditions are suitable for manual drilling, and has the potential to be used throughout Africa, and beyond, using data available in most African countries.

Ultimately, this work will support proposed international programs aimed at promoting low-cost water supply in Africa and enhancing access to safe drinking water for the population.

10 things to know about groundwater: 9 & 10

Hidden Treasure: 10 reasons to know more about groundwater / 2 priorities to take seriously – briefing note

What to find out more or get involved? Join the RWSN Sustainable Groundwater Development community on Dgroups.

9. In rural areas groundwater is often the cheapest source of safe drinking water

The capital cost of a borehole and handpump is about USD40 per person (say USD1.50 per person per year). The recurrent costs are about USD4.50 per person per year. The total is about USD6.00 per person per year. Piped schemes cost about twice as much.

[Source: WASHCost Working Paper 8, 2013, IRCwash.org]

10. In urban areas many people use shallow ground-water despite the fact that it is very vulnerable to pollution

The high cost of connection to piped water services makes it more attractive to use a private well despite the poor water quality

New Picture

[Source: Danert, K, Adekile, D and Gesti Canuto, J (2014) Manually Drilled Boreholes: Providing water in Nigeria’s Megacity of Lagos and Beyond, Skat Foundation http://www.rural-water-supply.net/en/resources/details/618]

High-Tech meets Low-Tech: Using remote sensing to help manual drilling

Drilling for water can be expensive: it can cost up to £10,000 to drill a borehole that will have a £500 handpump installed on it.  However, there are alternatives – manual drilling methods are often most effective and just as good quality, but the challenge for the drillers is knowing where they can find good quality water.

Continue reading High-Tech meets Low-Tech: Using remote sensing to help manual drilling