CONTENT IntroductionStudy areaLiterature reviewMaterials and methods• Methods• MaterialsLimitationsResultsDiscussionsIntroduction:The problem of water resources and land management varies from simple to complex, even becoming a large-scale watershed management problem. . To address this kind of problems we basically used numerical models where the models deal with measuring runoff in a large catchment with different conditions such as soil type, land uses and catchment management conditions. To make watershed management effective some basic materials are needed such as: • GIS technology • Wide range of information and knowledge • Data required to run the models • Mind of an expert decision maker on the watershed scale This research can predict current watershed conditions watershed management, has the history of past watershed management. And the most admirable thing is that it can also be used to predict future watershed conditions....