As part of its Afar Soil Rehabilitation Programme (ASRP) in Ethiopia, the GIZ is building water-spreading weirs and dry-stone walls in seasonally flooded, dry riverbeds. These measures aim to increase soil stability and fill in erosion gullies by depositing soil sediment. Furthermore, the measures can help to slow or even prevent flooding. Water-spreading weirs and dry-stone walls also increase the medium-term water availability in affected catchment areas. The GIZ commissioned Unique to develop statistical methods to assess the effects of these measures, including their spatial impact via remote sensing data. The assessment methods developed also form the basis for long-term monitoring of these installations.

• Development of statistical methods for assessing the effects of water-spreading weirs and dry stone walls
• Assessment of the spatial impact using remote sensing data