Hydrographic Survey ensures safe barge access to Bethel - The Delta Discovery, Inc.
By Marta Kumle What is Hydrographic Surveying? Hydrographic surveys produce maps of an underwater area. They reveal the depths, physical features and objects on the bottom. Onshore topography is a 3D model of the shape of the land, based on measurements of locations and elevations. Underwater, bathymetry is the equivalent of topography: the elevation and
Source: deltadiscovery.com