Seepage and evaporation are the most serious forms of water losses in an irrigation canal networks. These losses are sometimes very high, of the order of 25 to 50% of water diverted into the main canal. Seepage is not only a waste of water, but also may lead to other problems such as water-logging and salinization of agricultural land. Additionally, the amount lost to seepage often falls within the discharge measurement errors of traditional methods. In this research, earthen trapezoidal canal has been considered for determination of seepage by numerical simulation using Geo-Studio software...