Sounding profiles

Depth transects from inshore approach surveys, updated each season.

Inner approach profile — northern harbour

Depth transects taken along the main approach channel at three-hour tidal intervals. Anomalous shoaling detected at two waypoints; cross-referenced against seasonal seabed movement records. Data supplied to Lumen Atlas for chart correction.

Depth datum review

Annual verification of chart datum against national tide gauge network. Corrections applied to three approach profiles. Results inform the charted depths published by Lumen Survey.

Eastern channel seabed survey

Acoustic substrate classification covering a 2.4 km reach of the eastern approach. Sand and gravel substrate confirmed; localised hard patches noted for anchor-caution annotation. Submission to the Atlas pending final review.

Methodology note

All depth records use chart datum as reference. Soundings are collected by single-beam echosounder and reviewed against tide predictions before archiving. Queries and corrections welcomed by email at depths@harbor-lumen.com.