Chalky & Preservation Inlets


Land Information New Zealand


6 Months



Project Date:




In early 2014 iXblue undertook the hydrographic surveying of the Chalky & Preservation Inlets for Land Information New Zealand (LINZ). Both Inlets are located in the pristine Fiordland National Park located in SW New Zealand, an area of untouched natural beauty.  Due to the increase in the number of large cruise ships visiting the area, LINZ wanted to minimise the potential for maritime and environmental disaster by ensuring that mariners are navigating with up to date charts.



Specifications for the survey required the use of a Multibeam Echosounder (MBES) to obtain full sea floor coverage and guarantee detection of sea bed features that could be dangerous to surface navigation. 


  • The remoteness of the area meant that we needed to be fully equipped and provisioned for a full survey period of 48 days.
  • The survey of the outer, offshore regions of this area could only be done during periods of calm weather.  


  • State of the art survey systems were installed in two utility vessels.  The 23m “TRANQUIL IMAGE” and the 15m “MACY GRAY” were mobilised in Tauranga in January 2014.
  • We used a third supply vessel to bring fuel, food and supplies to the survey area during the course of the project.  This allowed each vessel to remain operational for every day that they were onsite in the survey area.


In total over 3,600 linear nautical miles of MBES sounding was achieved between both vessels over an unbroken 48 day period between 21 January and 9 March 2014.

An important outcome of the survey was the discovery of a large natural sea-bed feature. This rock is located in the centre of eastern passage and has a charted depth of 6m. This one feature poses a major shipping hazard and could resulted in a maritime and environmental disaster if it was struck by a ship. 

The accurate surveying of the area and mapping of this hazardous feature has negated this risk. Vessels of all sizes can now navigate through this beautiful area with confidence and safety.  The risk of maritime and environmental disaster has been substantially reduced.