A thesis submitted m partial fulfillment of the requirement for the degree of Master of Engineering, School of Civil Engineering

Thesis (M. Eng.) - Asian Institute of Technology, 1994

This study attempts to measure the differences in benefits from and contribution to, irrigation system management by different farmer groups in an ethnically heterogenous community of water users, in a farmer developed and managed irrigation system. The system studied is in the Chitwan Valley in Central Nepal. The grouping of the farmers, evaluated based on several possible modes of grouping, has been found to have a significant influence of ethnicity and time of joining of the system. Keeping in view of the locational factor as well, seven groups of farmers have been identified. Universal, as well as case specific indicators have been defined for the evaluation of benefit to and contribution for irrigation system management. Water Availability has been evaluated as ratio of area cropped in dry year to normal year, yield and transplanting dates delay. The transplanting dates delay moreover, depends on the effect on water distribution due to the construction of a new canal . The participation of the farmer groups in the irrigation committee and their accessibility to social and physical structures have also been considered. Labour contribution has been evaluated based on the contribution in any Normal Year and in case of the major Flood rehabilitation for the Flood of July, 1993. The results of the analysis shows a difference in benefits and contributions among farmer groups of native farmers of Old Tharus and the newusers of the system: the Hill Migrants and the New Tharu group. But joint management, inspite of the differences in the benefit derived, the high contribution even by the less advantaged groups is seen. The benefits and the contribution outweigh each other, which leads to an enhancement in management strategies.