Water Level & Tides
OSI employs a wide variety of instrumentation to measure water elevation in lakes, rivers, and oceans. While astronomic tides are the most common driving force behind water level changes, water levels can also change due to environment conditions such as wind setup, dam releases, evaporation, rainfall, and runoff.
Today’s hydrographic surveys are most often vertically controlled by employing RTK GNSS or IAPPK techniques. OSI has a substantial inventory of state-of-the-art GNSS hardware (and processing software) used to realize precision water level measurements for hydrographic surveys.
OSI has supported various clients’ water level studies (including NOAA and the USACE) via water level recording, installation of permanent survey control (disks, deep rod marks, etc), precise leveling, and acquisition of GNSS observables for determination of ellipsoid-referenced elevations.