Two GeoSwath wide swath bathymetric sonars are being used for regular hydrographic
port surveys around the South Australian coast, providing bathymetry and side scan
data for use in the development and maintenance of this important national infrastructure.
Recent projects include the pre, progress, and post-dredge monitoring of the major
shipping channels to Port Adelaide and Port Giles which were deepened to accommodate
The Felix, a trailerable 5 metre NoosaCat 1800-Series boat with a mounting plate for a customised 250kHz GeoSwath transducer arm fixed to the port side gunwale.
The Pathfinder, an 11 metre NoosaCat 3900-Series boat with a 250kHz GeoSwath head deployed on a central 'periscope'-mount between the hulls.
HydroSurvey Australia is the hydrographic survey business arm of Flinders Ports,
with the core task of performing recurrent surveys of navigational channels and
berths for design and maintenance purposes. As well as using the GeoSwath data for
planning future port developments this survey programme is an integral part of Flinders
Ports' risk mitigation strategy. HydroSurvey now carries out regular navigational
hydrographic work at all the main shipping ports and minor boat havens in South
Australia, over 100km of channels and 50 berths.
As a core part of their expanding range of survey equipment HydroSurvey has taken
delivery of a second GeoSwath interferometric sonar from GeoAcoustics Ltd (Great
Yarmouth, UK), a Kongsberg Maritime Company. The wide swath width demonstrated by
their first GeoSwath (delivered in 2000 and upgraded in 2004) allowed unprecedented
rapid survey coverage in shallow waters, resulting in significant productivity gains
and achieving total insonification over large areas, with sounding data exceeding
IHO S44 special order survey standard for depth accuracy.
The two GeoSwath systems are mounted on HydroSurvey's NoosaCat twin-hulled survey
launches. The 'Pathfinder' is an 11 metre NoosaCat 3900-Series with a 250kHz GeoSwath
head deployed on a central 'periscope'-mount between the hulls. The 'Felix' is a
trailerable 5 metre NoosaCat 1800-Series with a mounting plate for a customised
250kHz GeoSwath transducer arm fixed to the port side gunwale.
In addition to their core survey functions, HydroSurvey Australia undertakes
contract hydrographic and bathymetric surveys for various projects including: design
and construction of commercial ports and marinas; locating shoals and reefs; and
to measure coastal sand migration. The GeoSawth Sonar's shallow water capabilities
also make it ideal for river and lake surveys; in 2001 HydroSurvey were commissioned
to survey Lake Burragorang (behind Warragamba Dam), 60km west of Sydney. With a
storage volume of 2 million megalitres this is one of the largest domestic water
supply dams in the world, supplying approximately 80% of the water delivered to
Sydney. Sydney Catchment Authority required a bathymetric survey to measure the
volume of sedimentation post-construction and to form a baseline for future surveys.
The 'Felix' performed the GeoSwath survey in a single field operation providing
total bottom coverage of the lakebed to the existing water level.