Water Harvesting Explorer: Decision Support for Climate Adaptation

Water security
Burkina FasoChadMaliMauritaniaNigerSenegal

The Water Harvesting Explorer is a decision support webtool that helps identify sustainable small-scale water harvesting interventions in the Sahel and Horn of Africa (HoA). The online tool is based on publicly available datasets and expert-validated typologies. It supports spatial and financial planning for implementation of water harvesting, by matching local conditions with appropriate small-scale storage solutions, such as planting pits, microbasisns, contour barriers and many more interventions.

Key Takeaways

  • This map-based tool helps to match water harvesting options to local site conditions.
  • Based on multiple environmental characteristics, including climate, land use, slope, and soil.
  • User-friendly and custom: A practical survey for local conditions is included.
  • Offline access via the mobile GIS tool QField for use in the field.
  • Developed through broad collaboration with leading water and land management organizations.

Project Details

Started: 2021 – To be completed: no end date
Ref: 201148 | Status: Ongoing
Project title: Water Harvesting Explorer± Decision support tool for small-scale water storage intervention planning

Background

Water scarcity and land degradation threaten food and water security in the Sahel and Horn of Africa (HoA). While many techniques for water harvesting and land restoration have been successfully applied in the region, it is often unclear which specific intervention is most suitable for a given local context.

The Water Harvesting Explorer (WHE) webtool responds by combining geo-data with typology based recommendations. It lowers the barrier for non-specialists to assess, plan and initiate sustainable water interventions at the landscape level.

Activities

Acacia Water created the webtool that uses maps based on precipitation, slope, land cover, and soil to identify suitable water harvesting techniques. By selecting a location on the map, users get tailored intervention options.

A rapid survey refines these suggestions based on local socio-economic conditions. The underlying interventions are drawn from the database of WOCAT (World Overview of Conservation Approaches and Technologies).

This is an international platform documenting sustainable land management practices from around the world, and validated by experts. Notifications alert users to protected areas, erosion risks, transboundary aquifers, and more.

Findings

The Water Harvesting Explorer brings together over 60 verified interventions and bio-physical datasets. It enables targeted planning based on evidence and experience, and includes safeguards like erosion warnings and protected area flags.

The platform continues to evolve. It offers practical value for planners, NGOs and communities. Users are encouraged to provide feedback and contribute new practices via the WOCAT platform.

Project Areas

The Water Harvesting Explorer covers the Western Sahel and Horn of Africa.

The Western Sahel is a semi-arid region in West Africa, stretching across several countries. It lies on the southern edge of the Sahara Desert. The climate is defined by a distinct wet and dry season. The region experiences very hot temperatures, with daytime highs often exceeding 40°C (104°F) during the dry season. Irregular and low rainfall is a key challenge for agriculture and water resources in the region.

The environment is prone to desertification, soil erosion, and water scarcity, making it vulnerable to the impacts of climate change. It faces ongoing challenges related to food security, water access, and sustainable land management practices.

The Horn of Africa’s landscape is diverse and shaped by contrasts between arid deserts, rugged mountains, and fertile highlands. Towering plateaus and hillsides rise above savannas and valleys. There are deep fissures, lakes and volcanic features. Along the coasts, the terrain shifts to dry lowlands and stark salt flats. One of the hottest places on Earth is located here: the desert Danakil Depression.

The climate of the Horn of Africa is as varied as its terrain, ranging from extremely hot deserts to cool highlands. Much of the region, is dominated by hot, dry, and arid conditions with minimal rainfall. Seasonal winds bring rainfall to parts of the region, though it is often irregular and unpredictable, contributing to recurring droughts. This variability in climate has shaped both the ecosystems and the livelihoods of people in the Horn, making water and resource management central to survival.

Geographic scope: Transboundary

Downloads and Links

Export Export Water Harvesting Explorer Webtool

In Cooperation With

Commissioned by:

The World Bank

Funded by:

The World Bank

Project partners:

Acacia Water WOCAT (World Overview of Conservation Approaches and Technologies) MetaMeta AidEnvironment IHE Delft Institute for Water Education (UNESCO-IHE Delft) Verdant Earth Global Water Partnership West Africa (GWP) Stockholm Resilience Centre UNESCO-IGRAC

Contact

Maarten Waterloo

Ecohydrologist

+31 6 83 56 08 09
maarten.waterloo@acaciawater.com
dr-maarten-waterloo-0b35477

Related topics:

Climate resilience, Drought, Nature-based solutions (NbS), Online platform, Small-cale interventions, Water harvesting, Water scarcity, Webtool

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