Groote Eylandt: Submarine Cable Connecting Remote Communities
The Groote Eylandt submarine cable is a 95-kilometer-long fiber optic system connecting
Alyangula on Groote Eylandt to
Numbulwar on mainland Australia. Owned by Telstra, it was recorded as ready for service in 2011 and remains listed as in service. This cable plays a role in providing telecommunications connectivity to Groote Eylandt, a remote island in the Gulf of Carpentaria known for its manganese mining and Indigenous communities.
What makes the Groote Eylandt cable particularly interesting is its role in connecting an isolated region with limited alternative infrastructure. Publicly available information about its technical specifications, such as design capacity, fiber pairs, and supplier details, is sparse, leaving questions about its full capabilities and operational scope. This lack of transparency is not uncommon for smaller, regional submarine cables.
Quick facts
| Length | 95 km |
| Ready for Service (RFS) | 2011 (GeoCables database value; no conflicting sources surfaced) |
| Owners | Telstra |
| Status | In service |
| Design Capacity | Not disclosed |
| Fiber Pairs | Not disclosed |
| Supplier | Not disclosed |
| Technology | Not disclosed |
| Landing Points | Alyangula (Australia); Numbulwar (Australia) |
| One-way Latency Floor | ≈ 0.5 ms |
| Round-Trip Time (RTT) Floor | ≈ 0.9 ms |
Route
The cable connects Alyangula, a township on Groote Eylandt, to Numbulwar, a small coastal community in the Northern Territory of mainland Australia. Groote Eylandt is located in the Gulf of Carpentaria, approximately 50 kilometers off the mainland. The cable traverses a relatively short but geographically significant corridor, linking an island with limited terrestrial connectivity to the mainland's telecommunications network.
Why it was built and what it carries
The Groote Eylandt cable was likely built to address the connectivity needs of the island's residents and businesses, including the manganese mining operations that dominate the local economy. Reliable telecommunications are essential for both industrial operations and community services, such as healthcare and education. While specific details about the cable's data-carrying capacity are not publicly disclosed, it is reasonable to assume that it supports broadband internet, voice communications, and other digital services for the island's population and enterprises.
History: what can be established
GeoCables records the cable as ready for service in 2011, and no conflicting dates have surfaced from industry sources. While the construction and deployment timeline are not documented in public records, the cable's operational status suggests that it has been serving its intended purpose for over a decade. Telstra, the owner, is a major Australian telecommunications provider with extensive experience in submarine cable systems, but specific details about the project's planning and execution are not readily available.
Capacity and technology
Publicly available data does not confirm the design capacity, fiber pair count, or the technology used in the Groote Eylandt cable. Without operator documentation, attributing specific capabilities would be speculative. Given its relatively short length and regional focus, it is likely less complex than large intercontinental systems but still engineered to meet the connectivity needs of its service area.
Latency: the physics
The computed one-way light propagation latency over the 95-kilometer wet segment is approximately 0.5 milliseconds, with a theoretical round-trip time (RTT) floor of 0.9 milliseconds. These values represent the absolute minimum latency achievable under ideal conditions, assuming light travels at 200,000 to 204,000 km/s in optical fiber. Real-world latency is higher due to additional factors such as land-based network tails, terminal equipment processing, and routing inefficiencies. No live measurements for this cable are currently available.
Redundancy: what happens if it breaks
If the Groote Eylandt cable experiences a fault, connectivity to the island could be disrupted. Redundancy options for this corridor are not documented in public sources, but alternative solutions would likely involve satellite communications or other terrestrial links, which are generally less efficient and more expensive than submarine cables. Repairing a fault would involve standard industry practices, including cable surveys, the use of specialized cable ships, and potentially deploying spare cable segments.
Bottom line
- The Groote Eylandt cable connects Alyangula on Groote Eylandt to Numbulwar on mainland Australia.
- It spans 95 kilometers and has been listed as in service since 2011.
- Owned by Telstra, its design capacity, fiber pairs, and technology are not publicly disclosed.
- Computed latency floors are ≈ 0.5 ms one-way and ≈ 0.9 ms round-trip, though real-world latency is higher.
- Redundancy options and repair logistics are not documented but would involve standard industry practices.