For studying the general disease of aqueducts of irrigation district, some aqueduct in various conditions of operation was simulated by using the finite element method with an example of the Danjiangkou Irrigation District. With the means of field detection, the reasons for the aqueduct diseases were analyzed and the risk for the practical state to use the aqueduct was scientifically identified. The results show that for satisfying the requirements of anti seepage and anti cracking, the use of prestressed concrete aqueduct is reasonable, safe. At the mean time, the process demands of CFRP (carbon fibre reinforced plastic) reinforced concrete aqueduct are briefly introduced.