What is bathymetric LiDAR scanning?

Bathymetric LiDAR scanning is a specialized survey technology that maps underwater surfaces by using laser wavelengths capable of penetrating water. While standard topographic LiDAR uses near-infrared lasers (which reflect off the water surface), bathymetric systems use green or blue-green wavelengths (typically 532nm) that pass through the water column and reflect off the seabed, riverbed, or underwater structures.

How Bathymetric LiDAR Works: The system fires dual-wavelength laser pulses simultaneously:

1. Near-infrared pulse: Reflects off the water surface — determines the water surface elevation
2. Green-wavelength pulse: Penetrates the water — reflects off the bottom to determine depth

The difference between the two returns gives the water depth at each point. Modern bathymetric LiDAR systems capture 1-2 million data points per second, combining topographic (above-water) and bathymetric (below-water) data in a seamless dataset.

Depth Penetration: Bathymetric LiDAR typically penetrates 10-40 meters deep depending on water clarity. Clear tropical water allows maximum penetration; turbid or sediment-laden water reduces effectiveness. The technology works best in shallow coastal areas, harbors, rivers, and lakes.

THE FUTURE 3D Equipment: We operate the BathyLogger BL200 echo sounder alongside drone LiDAR for comprehensive above-and-below waterline documentation. The BL200 provides precision depth measurements with full NMEA compatibility, integrating with positioning systems for georeferenced bathymetric profiles.

Applications:

• Port and harbor infrastructure: Map wharf structures, berth depths, underwater obstructions, and dredging verification
• Coastal engineering: Shoreline mapping, beach nourishment monitoring, sea wall inspection
• River and waterway surveys: Channel depth mapping, bridge scour assessment, dam inspection
• Environmental monitoring: Reef mapping, aquatic habitat documentation, erosion tracking
• Marine construction: Pre-construction bottom surveys, cable and pipeline route mapping

Deliverables:

• Combined topographic + bathymetric point clouds
• Bathymetric contour charts
• Cross-section profiles along channels or berths
• Volume calculations for dredging planning
• Georeferenced depth data compatible with hydrographic software

Learn more about our port and harbor 3D scanning services.