Marine Work Methods

Osborne dredging extends beneath the shiplift

Published 28 October 2026 Publisher IMWO Region Asia Pacific Confidence Confirmed
Osborne dredging diagram: under-lift cut, 1.8 km pipe outside the channel and end-November expectation

IMWO original osborne engineering diagram from the cited primary records

Osborne No.4 maintenance dredging covers the approach, berth and area beneath the shiplift. South Australia's October notice specifies a 1.8 km submerged pipe and an expected end-November programme.

The notice specifies a submerged pipe outside the channel

Temporary NTM 76/2026 gives Monday-Saturday hours of 07:00-19:00 and a 1.8 km submerged pipeline outside the navigable channel. Yellow buoys mark the pipe at 500 m intervals, with the stated white flashing light. The dredge listens on VHF 12, 14 and 16. ANI's asset account identifies the wharf, dry berth, transfer system and shiplift as elements of its Common User Facility.

The shiplift pocket requires controlled plant access

Dredging beneath a shiplift introduces working clearances and structural interfaces that differ from an unobstructed channel cut. The dredge approach, pipe connections and survey access have to accommodate the installed lift infrastructure. McConnell Dowell's wider CUF account describes river and shiplift-pocket dredging alongside structural upgrades, a wharf extension and dry-berth works. It establishes the facility's interacting work packages; NTM 76 itself leaves the current dredging contractor unnamed.

Evidence conclusion

The work plan needs a surveyed pocket and pipe corridor

The operator and dredging team need an agreed plant envelope beneath the lift, a surveyable excavation boundary and a pipe alignment that remains identifiable through the campaign. Pipe movements or maintenance can change that corridor even while the dredge stays inside the pocket. A joint daily plan should identify the active cut, lift restrictions and pipe configuration before vessel or lift movements are released. The November date is a programme expectation; a final pocket survey and the operator's operating release establish the usable result.

Outstanding evidence

  • Active pocket boundary and shiplift operating restrictions
  • Submerged-pipe alignment, marker condition and change notices
  • Final pocket survey and operator release

Related records 1

Subject index

Related subjects

These subject pages bring together related projects, technical articles, reports, and evidence methods.

Sources used 4

Source collections