Sustainable Climate Resilient Water Supply for Wag Himra?

EU RESET II Groundwater Mapping Project – Zonal consultation meeting in Sekota, Wag Himra Zone, Amhara Region

By Jane Bevan
20 March 2019

In a public meeting hall in Sekota town, over 25 participants representing the eight different woredas (districts) in the Wag Himra Zone, the zonal and regional water authorities and the RESET[1] NGO partners came together to review the groundwater suitability maps created by the mapping project, and prioritise areas for detailed hydrogeology mapping and subsequent drilling.

The Wag Himra Zone is renowned in Ethiopia for its challenging water situation and resultant severe droughts, mainly caused by low rainfall and a difficult geology for finding groundwater. Water often appears on the surface and shallow wells are possible, but deeper groundwater sources are limited and there have been many unsuccessful deep boreholes drilled. In periods of drought, which have become more frequent in recent years, surface water and shallow wells are some of the first sources of water to dry up. Communities are then often having to travel long distances to fetch water. Climate resilient water supplies are key to reducing vulnerability of the population and improving the resilience and sustainable development of the region.

The UNICEF groundwater mapping programme, which combines geohydrological maps with overlay layers of remote sensing satellite imagery to create water suitability or probability maps, has successfully targeted fresh water boreholes in other drought-prone areas of Ethiopia where previous positive drilling has been limited.

Hence there is hope that this approach is more likely to succeed. The first step after the creation of the maps was to ‘ground-truth’ the findings – that is to conduct geological field surveys to verify the maps.[2] This resulted in some fine-tuning and adjustment of the ‘weighting’ parameters of the remote sensing overlay layers[i]

Groundwater Suitability map of Wag Himra Zone
Groundwater Suitability map of Wag Himra Zone

This mapping, supported by the EU, is part of UNICEF’s contribution to the Climate Resilient Strategy of the OneWASH National Programme of Ethiopia[3]. It also addresses the ‘leave no one behind’ equity agenda of the SDGs by reaching communities in difficult hydrogeological environments. Groundwater suitability maps are being developed in 41 of the most drought-prone woredas of the country, and similar consultations are taking place in other RESET clusters in Oromia, SNNP, Afar and Somali regions.

Returning to Sekota, after producing the suitability map which show areas of stronger groundwater potential, the next stage is to assess priorities and need in the region and to understand where the greatest demand lies. During the meeting, each woreda representative shared their detailed local knowledge of the water situation, and the size of the communities at risk. Once priority areas have been selected by these stakeholders, the field teams will conduct detailed ground geological and geophysical studies in areas where the greatest demand and high groundwater potential align.

Wag Himra has a complex geological setting, predominantly made up of crystalline impermeable basalts.   Some of the basalts do yield water in areas where they are sufficiently fractured at depth to have some permeability and hence hold groundwater. It is expected that detailed geophysical surveys will identify areas where higher permeability is likely. However, even successful boreholes in this region have had quite low yields.

Whilst this mapping hopes to realise new untapped resources, it also gives us a unique opportunity to view the region holistically in terms of water potential. There have been discussions among the experts involved in the project of alternative water extraction methodologies such as well-fields, combining low-yielding boreholes to produce sufficient water, of artificial recharge, or of fracturing basalts at depth to increase permeability.  All such options will need to be researched and evaluated to determine what is realistically possible. However, there was a keen sense of collective effort among the meeting participants to ensure that solutions are found.

The groundwater maps described in this report are being developed by UNICEF as part of the EU RESET II (Resilience in Ethiopia) Project, which targets 8 clusters of drought-prone woredas throughout the country. UNICEF has enlisted the support of the Joint Research Centre of the European Commission, Acacia Water consulting firm, and key geological experts in the country. Stakeholder consultations like the one in Wag Himra are a crucial part of the process for tapping into the considerable local knowledge and aligning suitability with demand. Once finalized, the groundwater potential maps will remain a valuable resource of the Government of Ethiopia for further use and exploration.

[1] RESET: EU-supported programme of resilience in Ethiopia

[2] See article on combining ground water mapping capacity building 

[3] ONEWASH National Programme

[i] For a detailed description of the mapping process please see Learning note  Using GIS and Remote Sensing to Access Water in the Drought-Prone Areas of Ethiopia and Madagascar