| The purpose of this paper is to suggest possibility of the application of the middle and small river channel planning by photogrammetry with digital aerial cameras. We have obtained the spots of surface elevation both topographical survey in river with VRS-GPS or Total Station and photogrammetry with digital aerial camera (UltraCamX)， and evaluated numerical differences of longitudinal water level by 1D-flow analysis using those spots. As a result， the differece of cross section area(per survey line) between topographical survey and photogrammetry(high-resolution 5㎝/pixel) is 0.8m2(0.03m2/m). The water level caluculation results were at almost same between using topographical survey dates and using photogrammetry(low-resolution 10㎝/pixel) edited by human. However， the edited photogrammetry required much processing time although it was accurate. We concluded that it is important to enhance accuracy by using a near-infrared photograph can identify the vegetation area and， as much as possible， to automate the measurements of surface elevation for the river channel planning. |
