The county of Sarpy is bounded as follows: Commencing at a point in the main channel of the Platte River, on the north line of section seventeen, township fourteen, north, range ten, east, the said point being now the northwest corner of said Sarpy County; thence due east to the eastern boundary line of the State of Nebraska as established by the Iowa-Nebraska Boundary Compact of 1943; thence south along said eastern boundary line of the State of Nebraska to a point due east of the main channel of the Platte River, where the same flows into the Missouri River; and thence up the middle of the said channel of the Platte River to the place of beginning.