Coastal Hazard Assessment · MCU25/0087

SandMap – Report of Survey for Sunshine Beach Profiles



           Seabed coverage
                  Method to ensure seabed coverage criteria is met
           Survey lines were run along pre-determined profiles and met up with land based survey work.
           Cross lines were run across the survey as a check.

                  Echo sounder pulse repetition rate
           Ping rate was 20 pings per second at 20m range.

                  Beam widths along and across track
           Beamwidth for the CEE ECHO system was 9° in diameter.

                  Survey vessel speed over ground
           SOG was generally 6 knots on average to maintain good data density and to ensure safe
           operation close to the beach.

                  Rejection criteria for line running
           Distance from profile line was set at 2m. Any deviation from this maximum limit was run
           again.

           Calibration and quality assurance
           Equipment was mounted to a fixed bracket and a pole and as such offsets were measured and
           incorporated within the software prior to the commencement of this survey. This
           arrangement has been used for many surveys in the past.
           All results for the checks detailed below can be found in Appendix C: Calibration Checks.

                  Static calibration method
           The Altus NR3 RTK GNSS unit was used to capture the beach profiles out to as deep as possible
           at low tide to provide overlap with the single beam acquired data. This overlap effectively
           established a small reference surface at each profile for comparison.
           Results were very good overall, especially noting the potential for sand movement in the surf
           zone area. There was approximately 4 hours between the RTK GNS


           S pole shots in the surf and the SBES acquired data due to having to wait for tides.
           Results detailed at Appendix C: Calibration Checks.




Rev. no.    Doc No.                                        Version Date          Doc Approver
  1         P0100-20251020                                 20/10/2025            Rod Tansley                        Page 11 of 20

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