In arid and semi-arid lands, rainfall arrives irregularly and leaves quickly. Rainwater harvesting — collecting, storing and conserving it — is a core part of Integrated Natural Resource Management (INRM). Done well, it improves soil moisture, reduces land degradation and strengthens community resilience to climate change.
Roof rainwater harvesting
Rain collected from rooftops through gutters is directed into tanks or reservoirs — reducing pressure on rivers and groundwater while improving water availability in dry periods.
- Install gutters and storage tanks at homes, schools, health facilities and community institutions
- Promote safe water storage and treatment
- Use harvested water for kitchen gardens, tree nurseries and household needs
Earth dams and water pans
These structures collect and store surface runoff during rainy seasons — supporting livestock production, dry-season farming and community water security when properly designed and managed.
- Construct and rehabilitate community water pans and small earth dams
- Establish appropriate spillways and erosion-control measures
- Promote community management and maintenance of storage facilities
Soil and water conservation
Contour bunds, terraces, infiltration trenches and semicircular bunds slow runoff and increase infiltration — reducing erosion, improving soil fertility and restoring degraded land.
- Establish contour terraces and infiltration trenches
- Construct semicircular bunds around trees and in degraded areas
- Promote mulching, cover crops and minimum soil disturbance
- Rehabilitate degraded land through vegetation regeneration
Sand dams and subsurface storage
Sand dams built across suitable seasonal riverbeds retain sand and store water within it — improving dry-season availability while losing far less to evaporation than open reservoirs.
- Identify suitable seasonal river channels through technical assessments
- Construct sand dams where hydrological and geological conditions permit
- Protect riverbanks and catchment areas through vegetation restoration
- Establish community systems for equitable water access
Water harvesting for agroforestry
Harvested water integrated with trees improves survival, restores vegetation cover, supports biodiversity and creates food and income opportunities.
- Establish water-harvesting basins around fruit trees and indigenous seedlings
- Plant drought-tolerant and locally appropriate tree species
- Integrate trees with crops and livestock systems
- Use harvested water to establish and maintain community tree nurseries
Part of a bigger system
Rainwater harvesting should never stand alone — it works as part of an integrated approach connecting water, soil, vegetation, agriculture and livelihoods.
| Natural resource | Harvesting intervention | Expected outcome |
|---|---|---|
| Water | Roof catchments, water pans, earth dams and sand dams | Improved water availability |
| Soil | Contour bunds, terraces and infiltration trenches | Reduced erosion, better soil moisture |
| Forests and vegetation | Tree planting and catchment restoration | Improved cover and biodiversity |
| Agriculture | Water-efficient irrigation and kitchen gardens | Better food security and productivity |
| Livestock | Water pans and managed watering points | Improved livestock productivity |
| Biodiversity | Restoration of riparian areas and degraded land | Healthier ecosystems |
| Climate resilience | Distributed storage and soil-moisture conservation | Reduced drought vulnerability |
What we prioritise in our working areas
In Kenya's drylands — Tharaka Nithi, Embu, Isiolo, Kitui, Makueni, Machakos and Laikipia — rainwater harvesting is a practical foundation for community-led natural resource management:
- Community water harvesting: household and institutional systems, and rehabilitated water pans
- Farmer-led soil conservation: terraces, contour bunds, trenches and mulching
- Agroecology and food security: harvested water feeding kitchen gardens, indigenous seed, fruit trees and diversified farms
- Landscape restoration: water harvesting combined with indigenous trees, natural regeneration and riparian protection
- Livestock and livelihoods: better water access for drought-resilient enterprises
- Community governance: water-user committees, bylaws and fair local allocation
- Climate information: forecasts and indigenous knowledge guiding storage and planting decisions
Getting it right
For rainwater harvesting to last, communities and implementing organisations need to:
- Assess catchments and confirm each structure suits its site
- Design for local rainfall, runoff volumes, soils and topography
- Avoid concentrating runoff in ways that flood or erode neighbours' land
- Protect water quality through treatment, safe storage and pollution prevention
- Keep enough water flowing for downstream users and the environment
- Include women, youth, persons with disabilities, farmers and pastoralists
- Set clear responsibilities for maintenance, financing and conflict resolution
- Monitor water availability, erosion, vegetation recovery and fair access
What success looks like
- More water available through dry periods
- Better soil moisture and less land degradation
- Higher farm productivity and household food security
- Improved survival of indigenous and fruit trees
- Restored biodiversity and ecosystems
- Less pressure on vulnerable water sources
- Stronger community participation in resource governance
- Greater resilience to drought and climate variability
- More household income from sustainable farm and livestock enterprises
The bottom line
Rainwater harvesting is more than a water conservation technique — it is a strategic approach to natural resource management. Combined with soil conservation, agroecology, agroforestry, catchment protection and community governance, it transforms rainfall from a seasonal challenge into lasting livelihoods and restored landscapes. For SACEP Kenya, it is a practical entry point for empowering communities to conserve resources, strengthen food systems and build climate resilience. Harvest the rain, restore the land, sustain livelihoods.