This inspection used an ROV to assess the visible condition of a submerged structural asset below the waterline, providing the client with practical evidence for maintenance planning without heavy operational disruption.
OVERVIEW
A client required a visual inspection of a submerged structural asset to assess condition, identify visible deterioration, and support future maintenance planning. The asset formed part of a waterfront structure, with key inspection areas located below water level and difficult to assess using conventional inspection methods.
To obtain clear visual evidence while reducing access burden and disruption, an ROV was deployed to carry out a remote inspection of the submerged structure. The system captured video and still imagery of the asset below the waterline, allowing the client to review visible condition without relying on a more intrusive conventional inspection approach.
THE CHALLENGE
The client needed to inspect the submerged condition of a structural asset in order to better understand its current state and identify any visible issues that could require further attention.
Submerged structural assets such as quay walls, waterfront retaining structures, bridge piers, dock walls, and other below-waterline civil elements can be difficult to inspect using traditional methods. Inspection zones are often located below water level, visibility may be affected by water conditions, and direct access to submerged faces, joints, edges, or defects can be limited. In many cases, conventional inspection would require a more complex setup, specialist personnel, and a greater level of coordination.
For the client, the challenge was to obtain useful and reviewable condition evidence from below the waterline without introducing unnecessary disruption, additional risk exposure, or a more operationally demanding inspection method.
WHY CONVENTIONAL METHODS WERE LESS SUITABLE
A conventional inspection approach can introduce several challenges when dealing with submerged structural assets.
Safety considerations
Below-water structural inspections can involve higher-risk access arrangements where direct personnel-based methods are considered. Depending on the asset and environment, the work may require specialist inspection teams, more involved planning, and additional control measures to complete the inspection safely.
Access limitations
Physical access is often one of the main barriers to effective inspection. Submerged structural faces, vertical walls, joints, toe areas, and underwater features can all be difficult to examine directly using conventional methods, particularly where water depth, visibility, or surrounding infrastructure limits access.
Higher cost and disruption
Traditional approaches can also increase the overall inspection burden. Depending on the structure and site conditions, a conventional method may require more setup, more personnel, more equipment, and greater operational coordination. Where the structure forms part of an active marine, industrial, or utility environment, the client may wish to avoid unnecessary disruption while still obtaining reliable inspection evidence.
For this project, the client required a lower-disruption solution that could still provide clear visual evidence of submerged structural condition.
ROBOTIC INSPECTION APPROACH
To address these challenges, an ROV was used to carry out a remote inspection of the submerged structure.
The ROV was deployed to inspect the below-waterline asset and capture high-quality video and still imagery of visible structural areas. This enabled the client to review submerged condition without relying on a more intrusive conventional inspection setup.
Using the ROV, the inspection focused on:
- Assessing visible condition of submerged structural faces,
- Reviewing joints, edges, and accessible below-waterline features,
- Identifying signs of visible deterioration, damage, movement, or surface condition issues where present,
- Capturing visual evidence for client review,
- Documenting observations to support reporting and maintenance planning.
This approach allowed the inspection to remain focused on the client’s key requirement: obtaining practical structural condition evidence from a difficult-to-access submerged asset in a controlled and efficient way.
INSPECTION SCOPE SUMMARY
- Remote visual inspection of the submerged structural asset
- Review of accessible below-waterline faces and features
- Capture of inspection video and selected still imagery
- Observation of visible structural condition issues where present
- Documentation of findings for client review and reporting
- Preparation of a structured inspection summary and output package
INTERNAL CONDITION EVIDENCE
A key part of the inspection was the ability to obtain clear visual evidence from structural areas below the waterline that would otherwise be more difficult or more disruptive to inspect using conventional methods.
The ROV provided imagery of submerged structural faces, edges, joints, and other accessible inspection areas, giving the client a clearer understanding of visible condition and supporting the identification of any issues requiring further attention.
SAFETY & OPERATIONS BENEFITS
One of the main advantages of the ROV-based approach was the ability to inspect the structure while reducing reliance on more access-heavy and operationally demanding conventional methods.
By using robotic inspection, the client benefited from:
Reduced personnel exposure
The inspection reduced the need for personnel to access a submerged inspection environment in order to gather structural condition evidence.
Improved access to below-waterline areas
The ROV was able to inspect submerged structural zones more effectively than would typically be possible through a conventional visual inspection approach.
Lower operational disruption
The inspection could be completed with less disruption to the surrounding site or asset than might be expected from a more traditional inspection method.
Efficient delivery of usable outputs
The client received clear footage, still imagery, and reporting outputs that could be reviewed and used to support maintenance planning and next-step decisions.
Outcome
The inspection provided the client with a clear visual record of submerged structural conditions, supported by video, still imagery, and structured reporting. This gave the client a practical basis for reviewing visible condition, identifying any areas of concern, and planning any further maintenance, monitoring, or follow-up inspection activity that may be required.
By using an ROV, the client was able to inspect a difficult-to-access submerged structural asset in a way that reduced access complexity, limited disruption, and avoided the need for a more operationally demanding conventional inspection approach.
Key Benefits Delivered
- Remote inspection of a submerged structural asset
- Reduced need for more intrusive conventional inspection methods
- Improved access to below-waterline structural areas
- Lower operational disruption during inspection
- High-quality video and still imagery for review
- Clear reporting to support maintenance and asset management decisions