The invention discloses a method and a
system for quickly calculating the area of water-passing cross section of a river channel, and belongs to the technical field of water conservancy
project management information. According to the method, existing river channel characteristic parameters and DEM data are built in a control and calculation terminal in advance, and
latitude and
longitude position information and
river water level
elevation data are obtained at the center position of a specified
river section by using an unmanned measuring ship loaded with RTK; dEM data are compared, parameters such as river bottom elevation,
floodplain and left and right
bank slope elevations of corresponding longitudes and latitudes are extracted, the river channel water-passing section calculation method based on the river channel elevation and the river channel
water level is established, the current river channel water-passing section area can be quickly obtained through the calculation method and fed back to a user, and the
hydrographic survey efficiency is improved.