Analysis of the role of long-term and short-term periods of inflow in reservoirs water resources planning

Predicting of inflow discharge to reservoir dams is very important in achieving the purposes reservoirs water planning. Due climate change and human activities upstream basins recent years, time series data has generally had downward trend. Therefore, estimating different statistical periods (long-term, medium-term short-term) analyzing it selection project undeniable importance. In this study, estimate 4 located East Azerbaijan province (northwest Iran) was performed, effect selecting each period resources planning analyzed. The results showed that depending on conditions basin, appropriate will be different. But general, choosing a short 15-20 years effective goals project.