This paper quantifies the impact of water management on the incidence of drainage
problems. It is based on an empirical study in the rice schemes of the Office du Niger.
The rice schemes face perpetual drainage problems at harvest, which incur increased
production costs as well as production and/or quality loss. The rice schemes discharge
water into natural depressions and their filling-up poses an ultimate bottleneck to the
disposal of drainage water. Results demonstrate that the principal causes of drainage
problems are the saturation of the drainage system with excess irrigation water and the
insufficient maintenance of the collector drains. Once the collector drain is no longer
saturated, maintenance of the tertiary drains becomes important, while the disparity in
harvest dates between adjacent fields always aggravates the drainage problem. Since the
benefits of individual efforts often accrue to neighbors or are dissipated throughout the
entire drainage system, water management practices related to drainage should be tackled
at the collective level using Water User Associations as a platform.