Sea4D for Ocean Infrastructure

Sea4D for critical Ocean infrastructure.

For subsea telecoms and data cables, platforms, grid interconnectors and offshore compute, from construction through operation.

The Scale

About 1.7 million km

of submarine telecommunications cable in 2025, carrying most international data.

ICPC, 2025.

The Problem Here

Operating at sea means reacting as conditions change.

Those conditions are least understood where it matters most, in the direct zone: the sea within 1,000 m of a vessel or Ocean infrastructure. Situational awareness is most critical here, and gains in efficiency, workability and safety depend on it.

SEA STATE

Forecast, or measured at a fixed point away from the work. Access, lifts and inspection windows all wait on the call.

8.2 days

a month on average when weather made UK offshore wind farms inaccessible.

ORE Catapult and The Crown Estate, SPARTA Portfolio Review 2020/21.

COLLISION RISK

Managed by visual and radar watchkeeping. Collision at sea and allision with infrastructure share the same cause.

52%

fewer high-severity close encounters using AI-assisted systems, across 139 container ships over 12 months.

NorthStandard P&I Club, April 2026.

POSITION INTEGRITY

Reliant on continuous GNSS (GPS). DP station-keeping, gangway connections and zone monitoring all depend on it.

13,000

vessels affected by GPS jamming in a single quarter of 2025

Windward.

The Answer

Across the direct zone.

The 500 m safety zone sits inside the structure's direct zone, the sea within 1,000 m of it. Today the zone is watched by guard vessels, AIS and shore radar, and the MCA warns that turbines can mask small craft on a ship's radar. Sea4D monitors the safety zone and the direct zone around it from the structure itself, including vessels that do not transmit AIS, and logs each contact it detects and tracks.

The MCA expects operators to monitor vessel traffic through construction and operation, and to evidence safety-zone infringements. Its guidance lists radar, AIS and CCTV among the means.

(MGN 654, paragraphs 4.15 and 6.6)

AIS data alone is not an appropriate traffic survey.

(MGN 654, paragraph 4.6)

Close to an array, turbines can produce reflected and side-lobe radar echoes that mask real targets, and suppressing them risks losing small craft.

(MGN 372 Amendment 1, paragraph 2.9)

After a cargo ship struck a turbine in the German North Sea in April 2023, Germany's federal investigator recommended radar surveillance and monitoring beyond the 500 m safety zone.

(BSU investigation report 192/23)

G+ and IMCA both share lessons from crew transfer vessels striking turbines.

(Energy Institute Toolbox; IMCA safety flash)

SAFETY ZONE MONITORING

Safety zones and the traffic around them, monitored from the structure, with units combined for full coverage and the MGN 654 evidence backed up to the cloud.

SEA STATE AT THE ASSET

Measured at the point of work rather than forecast, giving workability and transfer windows.

VERIFIED PICTURE

A measured contact picture independent of what vessels broadcast, with GNSS interference flagged in the sea around the site.

Every record supports the operator's ALARP demonstration: measured sea state, the contacts detected and tracked, and position integrity, logged as evidence for risk assessment and review.

The Safety Zone

Under the UN Convention on the Law of the Sea and IMO guidance, coastal states may set safety zones of up to 500 m around offshore installations and structures. In UK waters, oil and gas installations carry statutory 500 m safety zones under the Petroleum Act 1987, and working vessels, construction spreads among them, are given advisory clearances through Notices to Mariners. Sea4D monitors the zone from the structure or the vessel: approaches, infringements and the sea state, logged as the operator's record, with units combined for full-zone coverage.

The Market

What the built Ocean runs on.

Submarine telecommunications cables suffer 150 to 200 faults a year worldwide, most of them from fishing and ships’ anchors (ICPC).

Subsea Cable Networks

Submarine telecommunications cable carries most international data. Sea4D monitors installed corridors and crossings from the nearest structure, with evidence for repairs, claims and consents.

Interconnectors and Platforms

Fixed assets in open water, monitored from the structure: zones guarded, sea state measured at the asset, consent obligations evidenced.

Offshore Compute

The newest application. Offshore data centres and compute at sea are structures in the water like any other. Sea4D monitors the vessels approaching and measures the sea state at the asset, with the record for the consent.

Weather-restricted operations.

DNV-ST-N001 reduces the operational limit for forecast uncertainty and allows a smaller reduction where site monitoring meets its accuracy and reliability requirements. Sea4D is designed to provide that monitoring at the point of work, with its accuracy verified in production trials, and the record goes to the marine warranty surveyor.

Cable lay and burial.

Set today against a forecast limit reduced for its uncertainty. Sea4D on the lay vessel is designed to measure the sea state and the vessel's motion at the stern through the lay, with the record for the marine warranty surveyor.

ROV operations.

Decided today on a forecast and the deck crew's judgement at the launch and recovery system. Sea4D at the launch point gives a go or no-go drawn from the measured sea state.

Lifts and installation.

Foundations, modules and transition pieces are lifted against a forecast limit. Sea4D at the crane or on the structure measures the sea state at the asset for the whole operation.

One unit, fitted to the working system: the lay chute, the launch and recovery system or the crane, as well as the vessel or the structure. Projected production-unit behaviour; to be verified in production trials.

Next Step

Get in touch.

For further information, or to discuss working together, please contact us.