Abstarct: In today’s world factors like significant growth in population and excessive use of natural resources for economical purposes have had impacts on water resources. It should be noticed that it is impossible to increase the sources of fresh water for solving this crisis. The only possible solution would be water management of existing resources and improving the methods of use. Building dams has been a known way for water management since thousands of years ago. Although number of dams has increased in the past few decades, sedimentation has always been the most important factor in reducing the useful life of dams and many reservoir dams has been abandoned because of being filled with sediment. Various methods such as excavation, hydro suction, bypassing systems, etc. exist for sediment removals of dams. Using these methods are limited and exact quality-quantity control of removed sediment is difficult and will cause decrease in reservoir’s water volume. In addition it is unnecessary to fully remove sediment because of environmental problems and financial issues. Sediment removal also makes it possible for crucial parts of dams like valves to continue working. Hydro-suction is one of the effective techniques in solving the problem of sedimentation in reservoirs which has a local impact and is usually used for removing sediments settled around the entrance valve of plants. “Burrowing type sediment removal method” is one the newest model of Hydro-suction. In the presented research the effect of changes in height of water on sediment and syphon height on efficiency of sediment discharge “Burrowing type sediment removal method” with use of laboratory model in two different diameter of pipes was studied. The results showed that in mentioned method in a certain upstream and downstream head difference, reduction in water level results in increase of efficiency. Also increase in syphon height results in decreased efficiency because of Head loss growth in pipe.