Water Levels and Tides

Monitoring water levels, tides and their currents is an important field of study for many applications, including ship navigation and port operations, government defense, coastal zone engineering projects, ecological studies, and even commercial and recreational fishing.

HydroLevel Mini Buoy

Traditional tide and water level monitoring uses shore-based tide gauges. The limitations to this method include availability of the land when there are permitting, operational, safety, and security challenges. If onshore tide gauges are not available, a combination of techniques such as tidal constituents databases, tidal zoning and hydrodynamic modling produce estimates of chart datums and tide correctors. This modeling is based on best available information and due to this uncertainty of model input, the water level error can be 40-60% of the total depth solution.

AXYS has developed an electronics payload using  DGPS to accurately monitor water elevation in any body of water where a surface following buoy can be deployed. In addition to position measurement, a motion sensor on the buoy measures the pitch, roll and heading of the buoy in real time. This data, along with earth tide corrections are supplied to the buoy’s processor, which performs tilt corrections, averaging and filtering. It enables depth positions to be measured on the absolute three dimensions and eliminates the need to estimate water levels The AXYS HydroLevel™ technology is available on many buoy platforms, enabling the system to be used in differing environmental conditions.