Analysis of farmers' perception about sealing techniques for runoff harvesting ponds: the case of Burkina Faso.

Arid and semi-arid areas are characterized by low annual rainfall that is unevenly distributed in time and space. These low and variable rainfall conditions are exacerbated by the effects of climate change, resulting in increasing agricultural losses for rain-fed crops. To overcome this, several water conservation techniques have been developed to safeguard agricultural yields. For example, supplemental irrigation using catchment basins is a climate change adaptation solution that has been promoted for many years in drought-prone areas. Unfortunately, this technique has had limited success in the Sahel due to the large amount of water lost through infiltration into the basins. These losses are closely related to the type of lining chosen to seal the runoff collection basins. Using a factorial analysis model, this paper highlights farmers' preferences for four of the most popular liners in Burkina Faso. Based on Waso-2 method, the survey was conducted in 2022 among 41 pond-owning farmers in the Central, Central Plateau and Central South regions. The results clearly show that the choice of liner has little to do with its availability and cost: producers focus all their attention on the liner's ability to improve the watertightness of their ponds and on the complexity of its maintenance. Concrete is therefore the first choice of producers as it is the most watertight, weatherproof, and durable, but also the most expensive. It is followed by plastic sheeting, a highly waterproof material available on the market, but not very durable. Clay comes third, despite its availability and low cost. Well-known in traditional architecture for ensuring the comfort of buildings, clay has proved ineffective for waterproofing submerged structures where the ground is unstable or cracked. Bitumen came last, as it is little known for pond protection and is not available in rural Burkina Faso.

Keywords: Rainwater harvesting basin, sealing solutions, supplemental irrigation, Waso-2.