Hydrographic Surveying 1.2 to 1.3 most important

Measurement and description of physical features of bodies of water and the prediction of their changes over time

Safe and efficient navigation

Measure → Reference → Process → Represent → Decide

Where is the sounding? (Defines coordinate reference framework)

Relative to what level? (References water surface elevation and reduced depth)

Reconnaissance → Planning & preparation → Horizontal control → Vertical control → Topographic survey → Hydrographic survey → Map preparation

Purpose, Extent, Method, Resources, Schedule, and Risk

Reconnaissance

Mapping the adjacent land-water interface (shoreline, banks, structures, aids to navigation)

Measuring the bottom and submerged features (positioning depths, detecting hazards)

Platform, Positioning, Depth sensor, Ancillary sensors, Checks, and Backups

Ingest → Correct → Clean → Verify → Build → Archive

Ensuring survey data quality and consistency before demobilization