This case study was made in Kiru Valley in the northeast Tanzania in order to study the water management to get a picture of which institutions that are involved, how conflicts are resolved, and also to see if all farmers in the area have an influence in the management. The area consists of big-scale farmers, small-scale farmers with IFAD irrigation scheme and small-scale farmers without irrigation scheme. The irrigation scheme was built in 2004 in the villages Mawemairo and Matufa. Mapea village is located downstream and has got less water after the scheme was built. The case study was conducted by semi-structured interviews with some officials at different institutions in the District, Mawemairo and Mapea and also with some farmers in Mawemairo. The results were mainly analysed with Integrated Water Resources Management approach which have been adapted by Tanzania government. Mawemairo and Matufa have established a Water Users Association (WUA) and the water management seems to work quite good for those who are members of this. But those farmers who are not members of a WUA seem to be outside of the management of the rivers in Kiru Valley. What is missing is a platform where all relevant stakeholders in Kiru Valley, like farmers, can participate in the decision-making and where conflicts can be resolved.