Scroll downscroll down button
Telstra Cable Crossing Design – Darwin Harbour

Telstra Cable Crossing Design - Darwin Harbour

Benefits
Atteris delivered a cost-effective design to Telstra for a submarine telecommunication cable crossing over several major gas pipelines in Darwin Harbour. The design used the maximum horizontal bending radius of the telecommunication cable and the most optimum seabed conditions to cross the pipelines. Crossing locations were identified where there was sufficient quarry rock cover. This provided the necessary separation distance between the cable and each pipeline without the need to prepare the crossing locations with additional quarry rock or concrete mattresses. The work performed by Atteris in close communication with Telstra and the pipeline operators resulted in an optimised, feasible, and cost-effective route for the cable.
Background
Telstra needed to install a new telecommunication cable across Darwin Harbour, between Mandorah and the city of Darwin. The cable would need to cross two existing major gas pipelines and the route of a proposed new gas pipeline. All three pipelines run parallel in Darwin Harbour and are approximately 100 m apart. The two existing pipelines are covered in a protective layer of quarry rock; however, the rock cover is very limited in places. The new gas pipeline is installed after cable installation. Therefore, this pipeline crosses the Telstra cable. Atteris performed the design and the engineering interface between Telstra and each of the pipeline operators. Separation distances were agreed and proposed crossing locations were reviewed by all parties. Telstra liaised with the cable installation contractor regarding proposed routes and bending radii.
Work Performed by Atteris

The scope of the engineering work included:
• Review of as built data of the two existing gas pipelines
• Review of seabed bathymetry, and geophysical and geotechnical data in the crossing region
• Review of previously proposed route studies for the cable
• Explore several cable route options, and select the most attractive option
• Perform a detailed cable installation analysis using Orcina’s licenced OrcaFlex software to assess the feasibility of the selected route and to check for cable freespans
• Perform a cable on bottom stability analysis
• Liaise with the pipeline operators and Telstra, and the cable installation contractor regarding the cable route options.

left arrow
right arrow
Download PDF
Share on facebook
Share on twitter
Share on linkedin
resources

Related Posts

Maitland to Burrup Subsea Corridor Assessment
CASE STUDIES
Maitland to Burrup Subsea Corridor Assessment
  • Tags:
  • Shore Approach
  • Shore Crossing
  • Subsea Pipeline
Read More
Simpson Pipeline – Decommissioning Stability Study
CASE STUDIES
Simpson Pipeline – Decommissioning Stability Study
  • Tags:
  • Decommissioning
  • On-bottom Stability
  • Subsea Pipeline
Read More
Telstra Cable Crossing Design – Darwin Harbour
CASE STUDIES
Telstra Cable Crossing Design – Darwin Harbour
  • Tags:
  • On-bottom Stability
  • Subsea Pipeline
Read More