Supplemental irrigation based on runoff harvesting is a sustainable solution in the current context of water scarcity that is prevalent in Sahelian countries. Runoff water harvesting ponds (RWHPs) are increasingly being utilized for vegetable cultivation by producers. This study aims to analyze the cropping choices of producers benefiting from RWHPs in the Kadiogo and Bazèga provinces of Burkina Faso in the West African Sahel. A sample of 27 surveyed producers revealed a dominant preference for vegetable crops (93.46% of the total production) over cereals. The cropping choices are influenced by factors such as the crop resistance to dry spells, the water demand, the economic return, and the market demand. For the effective utilization of the basins, crop choices should consider the water retention capacity of the basin. Additionally, to enhance the retention capacity, it is advisable to line them using appropriate waterproofing techniques. Similarly, the selection of basin installation sites should consider the soil characteristics and site-specific considerations. The findings of this research highlight the potential of runoff water harvesting basins to significantly improve agricultural productivity and resilience in the West African Sahel, thereby contributing to enhanced food security and improved livelihoods for local farmers.

Obtaining accurate values of saturated hydraulic conductivity (K_sat) is very important for managing all natural or artificial processes involving water flow into soils. Double-ring infiltration (DRI) is one of the easiest-to-work-with techniques commonly used for K_sat determination. Unfortunately, when improperly used, it leads to important variations and inaccurate results. This study was designed to investigate the necessary conditions to reach the true-value or real-world saturated hydraulic conductivity (K_{sat-real-world}) in the field. For this purpose, the effects of two factors—namely, the measured infiltration data type (cumulative, instant rate, and average rate) and the related non-linear regression equation type—were analyzed. Measurements with DRI were performed with samples from 106 locations in three West African countries, namely, Burkina Faso, Mali, and Cote d’Ivoire. The soils were composed of loam, sandy loam, and sandy clay loam. The results show that when infiltration rates are used rather than cumulative infiltration non-linear regression curves, the variability between the measured K_sat and the real-world saturated hydraulic conductivity (K_{sat-real-world}) could reach from 2.2% to 58.8%. This variability was caused by the approximate amplification—according to the procedure used—of time-increment measurement errors. Extending the test duration to more than 4 h, especially when clay soils were involved, and using the exponential one-phase decay non-linear regression of the cumulative infiltration data based on a clear measurement protocol provided the K_sat values that were closest to K_{sat-real-world}.

Specific consumption is a key parameter in estimating the water demand and further optimising the sizing of Drinking Water Supply Systems (DWSS) infrastructure. DWSS are globally used to provide safe drinking water in urban and rural settings, and their design cost is critical for water authorities, especially in low-income countries. In this study, the optimal of the specific consumption value is carried out in Burkina Faso (West Africa). The methodology adopted a statistical analysis of operational data collected on 40 DWSS systems in Burkina Faso, further completed by a multiple correspondence analysis (MCA) of determinants of the water demand and cluster identification and analysis through Agglomerative Hierarchical Clustering (AHC). The results show that the actual consumption is lower than the common estimate used in sizing. Statistical analysis revealed that actual specific consumption is affected by various parameters, the most relevant of which are the reliance on alternative resources, the presence of waterways and the local climate seasonality. The average actual specific consumption is estimated at 3.83 ± 3.43 L/people/day. Finally, a decision tree for the choice of suitable specific consumption value as a function of the physical settings of a given area is proposed for optimal sizing of DDWS systems in Burkina Faso.