Hydrography

Hydrography refers to the mapping or charting of water's topographic features. It involves measuring the depths, tides, and currents of a body of water and establishing the topography and morphology of seas, rivers, and lake beds. Normally and historically the purpose of charting a body of water is for the safety of shipping navigation. Such charting includes the positioning and identification of things such as wrecks, reefs, structures (platforms etc.), navigational lights, marks and buoys and coastline characteristics. Hydrography does not include water quality or composition which are part of the broader field of hydrology.