During the development of water resources the characteristics of excitement, direction, and flow velocity, depth, points of bottom, temperature and chemical composition of water is to be taken into account. Some of these indicators are determined through the results of measuring single aerial photographs and their stereoscopic pairs. Making aerial photography (APS) of water surface on technology for topographic land survey enables obtaining only single overlapping aerial photographs, as the water surface is in constant motion. Stereoscopic pairs of aerial photographs can be obtained if photographing is performed simultaneously by two aerial cameras (AFA) with close elements of internal orientation. The author considers two technological schemes of using two AFA in aerial photography of water space: AFA are installed on one plane; AFA are installed one by one on two similar aircrafts. In the second scheme the aircrafts move in the same horizontal plane at a given distance one after another or parallel to each other. Aerial photography was produced by topographic AFA with f=70–200 mm. from aircraft types AN-2 and AN-30 FC. The accuracy of determining the depth of stereoscopic pairs of aerial images was investigated. For the first time it was proved that stereoscopic pairs of aerial images obtained at implementing the first technological scheme of installation in the aircraft of two AFA, show that any change in the scale of photographing by k2 times leads to an equal change in the accuracy, therefore, the first technological scheme has a limited scope. The accuracy of the depth determination at a certain accuracy of the problem solution given in the tables lets choose the technological scheme of the installation in the aircraft AFA, the type of AFA and the aircraft as well as the parameters of the aerial photos.