Pre-Bathymetric Survey – Dibba Fishing
Harbour

Pre-Dredging Bathymetric Survey – Dibba
Fishing Harbour

GIS Mappers conducted a pre-dredging bathymetric survey at Dibba Fishing Harbour, Oman, under contract from the Ministry of Agriculture and Fisheries (MOAF). The objective was to measure the seabed profile within the harbor area to aid in the planning and calculation of dredging volumes, facilitating safe and efficient harbor operations.

The survey used an Odom Hydrotrac Echo Sounder operating at 200 kHz to collect depth data, supported by a transducer and Valeport Tide Gauge for tidal referencing. RTK GPS and Total Station units were deployed for control and positioning. Tidal variations were continuously recorded at the breakwater by the tide gauge to enable reduction of depth data to Lowest Astronomical Tide (LAT).

GPS data, corrected and logged via navigation software, was transformed into UTM projection coordinates. Survey datum was referenced to WGS 84 horizontal and Mean Sea Level (MSL) vertical. Daily bar checks ensured accurate calibration of the echo sounder before each day’s operations.

The final bathymetry charts were produced at 1:750 scale, showing a relatively shallow seabed with irregular features. Exposed sediments and minor seabed undulations were observed, providing critical insights for MOAF’s future dredging plans in the harbor.

This project, successfully completed in April 2012, showcases GIS Mappers’ capabilities in delivering accurate pre-dredging marine surveys using advanced hydrographic equipment and sound methodology across coastal Oman.