Detailed three-dimensional mapping of the seabed off Fremantle has been undertaken to make it safer for competitors and officials participating in this week's inaugural Perth Sail Grand Prix event.
Detailed three-dimensional mapping of the seabed off Fremantle has been undertaken to make it safer for competitors and officials participating in this week's inaugural Perth Sail Grand Prix event.
The Department of Transport and Major Infrastructure (DTMI) has applied the most advanced mapping technology and delivered seabed information with detail that is unmatched for an aquatic event staged in WA waters.
As part of the formal approval process for SailGP, DTMI considered a range of issues including safety risks above and below the waterline prior to its endorsement of the event at Bathers Beach on 17 and 18 January 2026.
DTMI Maritime Coastal Information Director Jenny Bothma said a new, more detailed approach to event seabed investigation saw technicians combine traditional hydrographic sonar data showing water depths with drone captured high resolution laser scan data, known as LiDAR, providing above water features.
"The result was a very detailed 3D computer model of the racecourse and surrounding seabed showing known areas of concern including the location of the enduring underwater piles of the original Fremantle Long Jetty extending west from Bathers Beach and also the depth of water around the breakwaters at South Mole and Challenger Boat Harbour," Ms Bothma said.
"The model is an invaluable resource for organisers to use to identify hazards and eliminate safety risks.
"The new, very detailed data not only gives organisers greater confidence to safely manage this large international event, it also provides valuable additional information for DTMI's nautical chart for the area - boosting ongoing safe navigation by commercial and recreational craft."
The mapping also provided more detailed information about the location of the known shipwrecks off Bathers Beach that has already been shared with the WA Museum.
DTMI continues to work closely with the SailGP to ensure the required safety management plans are in place for the two days of racing and in regard to the staging of the event at Fremantle Fishing Boat Harbour (FFBH).
As manager of the harbour, DTMI has worked with the organisers to plan access points to the ticketed viewing areas on South Mole and at Bathers Beach, house support vessels and the racing craft and about managing the large crowds of visitors and locals expected to attend the event.
View DTMI's 3D seabed model . This and other bathymetry data is available on DTMI's WA Bathymetry Portal .
Skippers can view the on-water closures for the event on the DTMI website .
To plan a visit to FFBH visit our Fremantle Fishing Boat Harbour webpage .
