The siphon pipe-line,named Shuimogou,is the largest structure on the main canal of the Yinda-ruqin irrigation project.Characters of which,as following:structural style-double pipes on bridge,designed water pressure-68 m,total lenth-2×568 m,inside diameter of the pipes-265 m,designed discharge-36 m\+3/s.So far as above,the worths to be designed,at end,the operational practice shows that,the designed scheme is successful and safely.