Our website uses cookies so that we can provide a better service. Continue to use the site as normal if you're happy with this, or find out how to manage cookies.

Support for Planned Dredging

The PLA can assist and advise on your dredging project throughout its lifecycle.

  • Pre Dredge Sampling
  • Pre and Post Dredge Surveys
  • Difference Models
  • Volume Calculations

Pre Dredge Sampling

Need to acquire and test samples pre dredging work?

The PLA can acquire surface samples using hand grabs and day grabs from a vessel, or collect from the foreshore.


  • Knowledge of the requirements
  • Fast turnaround
  • Options for additional testing


  • Sampling report including:
    • Charted samples locations
    • Chain of custody
    • Description of sample method


Pre and Post Dredge Surveys 

Need to know volume of material to dredge and confirm dredging performed as planned?

The PLA can acquire bathymetric surveys pre and post dredging operations.



  • Easy to take measurements from the data
  • Can identify defects
  • Historic record in case of any future damage
  • Can reduce diver time and focus attention to defects


  • full xyz point cloud
  • decimated xyz point cloud
  • Fledermaus scene file
  • Plots
  • Survey report(s) specifying including:
    • Controlling depths on the berths.
    • Outline of operations
    • The extent of any obstructions, scour or other notable features
    • Volume calculations, difference surfaces and associated specified deliverables will be included in the reported Post-Dredge survey.

Difference Models

Need to see changes over time?

The PLA can acquire surveys over the same areas at different times and generate difference models between these to show the changes over time.



  • Know about any scouring or accretion as soon as possible so action can be taken


  • Full xyz point cloud
  • Decimated xyz point cloud
  • Fledermaus scene file
  • Plots
  • Survey report(s)

Volume Calculations

Need to know volume of material to dredge to be dredged, or and confirm how much was material has been removed?

The PLA can use the bathymetric data to calculate the volumes you need to know, either planned dredge volumes, or post dredge.

Example of volumes for volumes for different target depth:



  • Facilitates dredging license applications
  • Can weigh the costs/benefits for different dredge depths
  • Offers an independent volume calculation, where contractors are on a per m3 rate


  • Survey report with required volumes
  • Chart showing the planned dredge area


Back to Hydrographic Services