Water harvesting is the collection, concentration, and storage of rainwater or surface runoff for various purposes, such as irrigation, domestic use, and livestock watering.
It involves a range of techniques and technologies designed to capture and conserve water resources in areas where water is scarce or unevenly distributed.
Similar terms: rainwater harvesting, runoff harvesting, water conservation, water catchment, water capture, water storage, water management, water saving, water use efficiency, water productivity
So, what exactly is Water harvesting?
Water harvesting is a sustainable approach to managing water resources by collecting and storing water from various sources, such as rainfall, surface runoff, and fog, for later use.
The main goal of water harvesting is to increase water availability and improve water security in areas where water is scarce or unevenly distributed, particularly in arid and semi-arid regions.
Water harvesting techniques can be applied at different scales, from small-scale household systems to large-scale community or watershed-level interventions.
Importance of Water harvesting in Kenyan Agriculture
Water harvesting is crucial for Kenyan agriculture, particularly in the arid and semi-arid regions that cover over 80% of the country’s land area.
These regions are characterized by low and erratic rainfall, high evaporation rates, and limited access to surface and groundwater resources. By adopting water harvesting practices, Kenyan farmers can increase water availability for crop production, improve crop yields and food security, and enhance the resilience of their farming systems to climate variability and change.
Water harvesting also contributes to soil and water conservation, reducing soil erosion and increasing soil moisture retention.
Types of Water harvesting techniques in Kenya
Several water harvesting techniques are commonly used in Kenyan agriculture:
- Rooftop rainwater harvesting: Collecting rainwater from rooftops and storing it in tanks or cisterns for domestic use, livestock watering, or small-scale irrigation
- Surface runoff harvesting: Capturing and storing surface runoff from roads, hillsides, or other catchment areas using structures such as check dams, terraces, or infiltration pits
- In-situ water harvesting: Conserving soil moisture by capturing and storing water where it falls using techniques such as contour bunds, tied ridges, or planting pits
- Floodwater harvesting: Diverting and storing floodwater from ephemeral streams or rivers using structures such as spate irrigation systems or flood spreaders
- Fog harvesting: Collecting water from fog using mesh nets or screens and storing it in tanks or reservoirs
Benefits of Water harvesting in Kenyan Agriculture
Adopting water harvesting practices in Kenyan agriculture offers several benefits:
- Increased water availability: Water harvesting increases the amount of water available for crop production, particularly during dry spells or droughts
- Improved crop yields: By providing supplemental irrigation using harvested water, farmers can improve crop yields and reduce the risk of crop failure
- Enhanced food security: Increased crop yields and reduced crop failures contribute to improved food security at the household and community levels
- Soil and water conservation: Water harvesting practices help reduce soil erosion, increase soil moisture retention, and recharge groundwater aquifers
- Climate change adaptation: Water harvesting enhances the resilience of farming systems to climate variability and change by providing a buffer against droughts and dry spells
- Cost savings: By reducing the need for expensive irrigation systems or water purchases, water harvesting can reduce production costs and increase the profitability of farming systems
Challenges in Implementing Water harvesting in Kenya
Despite the benefits, the adoption of water harvesting in Kenya faces several challenges:
- Limited technical knowledge: Many farmers lack the necessary technical knowledge and skills to design, construct, and maintain water harvesting systems
- High initial costs: The construction of water harvesting structures and storage facilities can be expensive, particularly for smallholder farmers with limited financial resources
- Land tenure issues: Insecure land tenure can discourage farmers from investing in long-term water harvesting infrastructure on their land
- Maintenance and management: Water harvesting systems require regular maintenance and management to ensure their effectiveness and sustainability
- Water quality concerns: Harvested water may be contaminated with pollutants or pathogens, requiring appropriate treatment before use
