This paper examines the management of irrigation in the Gezira Scheme, Sudan. It focuses on the tenants' management of water at the farm level. The authors argue that despite several decades of top-down instructions, Gezira Scheme tenants still retain their indigenous agricultural calendar. The calendar contains description of weather, rain, pests and possible yields and accordingly prescribes specific agricultural activities. This gives rise to informal channels of action which often contradict official instructions. Unlike the management of the Gezira Scheme, the authors do not take the informal channels as indicative of the tenants' lack of discipline, laziness or ignorance. Rather, they constitute innovative and practical response to Scheme inefficiency and bureaucratic rigidity. Most importantly, the adoption of these informal channels renders agricultural operations both practical and economically viable.