A framework for the use of decision-support tools at various spatial scales for the management of irrigated agriculture in West-Africa

The Kou watershed in south-western Burkina Faso has suffered from poor water management for several decades. Covering 1,800 km², this small watershed is the site of the second largest city in Burkina Faso (Bobo-Dioulasso), a former State-run irrigated rice scheme and several informal agricultural zones. Notwithstanding the abundance of water resources, most water users regularly face water shortages due to a population increase and low irrigation inefficiency. Local stakeholders therefore need low-cost, easy-to-use decision-support tools to enable them to monitor and exploit the water resources to best advantage at different spatial and user levels.
A top to bottom series of adapted water management tools has been successfully installed to address current problems, from watershed level (top) to individual field level (bottom), and including the 1,200 ha irrigated rice scheme. Remote sensing techniques have been developed to map the agricultural lands. Combined with data from a network of hydrologic gauging stations, regional water-use maps have been compiled. SIMIS software is being used for the public-private management of the irrigated rice scheme. A simple field-crop-water balance model, AquaCrop, is being used by extension workers to draft optimal irrigation charts. Day to day water use on irrigated plots was monitored by soil humidity and crop canopy measurements. Each water management tool is applied independently, requiring only limited data, but their combined results are contributing to improved integrated water management.