Subsea Surveillance Systems: The Eyes and Ears of Underwater Oil & Gas Operations

Introduction

The deep sea is one of the most challenging environments for oil and gas production. With equipment operating under extreme pressure, corrosive seawater, and remote locations, ensuring safe and efficient operations requires advanced monitoring—this is where subsea surveillance systems come in.

What is a subsea surveillance system?

Subsea surveillance systems are designed to monitor and collect data from underwater environments. They can track marine life, assess the health of underwater ecosystems, monitor oil spills, and ensure the security of underwater assets. These systems operate through a combination of sensors, cameras, and communication technologies, allowing for real-time data transmission to surface operators. It can be used to

• Inspect subsea equipment (wellheads, manifolds, pipelines)
• Detect leaks, corrosion, or structural damage
• Monitor marine life and environmental impacts
• Guide remotely operated vehicles (ROVs) during interventions

These systems provide high-definition video feeds from extreme depths to control rooms on platforms, FPSOs, or onshore facilities.

We covered the following topics in this blog:

✔ How subsea surveillance systems work
✔ Key equipment used in monitoring
✔ How operators control them from the surface
✔ Latest advancements in underwater surveillance

How does a subsea surveillance system work?

Subsea surveillance relies on a network of cameras, sensors, fiber optics, and remotely operated vehicles (ROVs) to collect and transmit data to control centers. Here’s how it works:

1. Data Collection (Underwater Monitoring)

• Sensors measure pressure, temperature, flow rates, and corrosion; acoustic leak detectors and corrosion monitoring probes; and sand and erosion sensors.
• Acoustic sensors listen for gas bubbles or unusual vibrations.
• Cameras  
  • Low-light and laser-assisted imaging    Provide visual and 3D mapping of subsea structures.
  • Lighting Systems
    • High-intensity LED arrays (20,000+ lumens)
    • Spectral tuning for water penetration
  • Sonar sensors emit sound waves to detect objects and map the underwater terrain by measuring the time it takes for the sound waves to return.
    • Depth-rated (3Km-4Km) High-definition cameras capture visual data, enabling operators to monitor the underwater environment and observe marine life in real time

2. Data Transmission to Surface

Transmission Methods: Once data is captured, it needs to be transmitted to the surface for monitoring and analysis.

• Cabled Systems: Fibre optic cables are commonly used for high-speed, reliable data transmission. They can carry large amounts of data over long distances without significant signal loss.
• Wireless Communication: Acoustic communication (using sound waves) or radio frequency methods are utilised in certain scenarios, particularly in areas where cabling is impractical.

3. Real-Time Analysis & Alerts Topside Processing Hub

Surface Control Room: Data from the subsea equipment is transmitted to a control room on a surface vessel or shore. Operators can use monitors to view live feeds and analyze data in real-time. Advanced software may be used to create visual representations of the data.

Key Equipment in Subsea Surveillance

How Operators Control Subsea Systems from the Surface

Controlling subsea systems from the surface involves a combination of technology, equipment, and communication protocols.

• Control Consoles: Operators use specialized control consoles equipped with screens, joysticks, and buttons. These consoles allow for intuitive control of the subsea equipment.
• Graphical User Interfaces (GUIs): Software applications provide visual representations of the subsea environment, displaying real-time video feeds, sensor data, and system statuses

Communication Systems

• Cabled Communication:
  • Fiber Optic Cables: Fiber optic cables enable lightning-fast data transmission, ensuring seamless real-time video and data communication.
  • Hybrid Cables: These cables can carry both power and data, enabling operators to control the system and receive feedback simultaneously.
• Wireless Communication:
  • Acoustic communication allows for limited data transfer over longer distances by using sound waves to carry data when cables are not practical.
  • Radio Frequency (RF): For short-range applications, RF communication can be employed, although it is less common for deep-sea operations.

• Data Transmission Protocols

  • Real-Time Streaming Protocol (RTSP): Commonly used for streaming video over IP networks.
  • Transmission Control Protocol (TCP)/User Datagram Protocol (UDP): These protocols manage data transmission, with TCP ensuring reliable delivery and UDP providing faster, though less reliable, transmission suitable for video feeds.

Challenges & Future Trends

challenges in Subsea Surveillance Systems

1. Environmental Conditions: Harsh underwater environments, including high pressures, low temperatures, and corrosive saltwater, can damage equipment and affect sensor performance.
2. Limited Communication: Traditional communication methods (like radio waves) do not work well underwater. Acoustic communication is often slow and has limited bandwidth.
3. Energy Supply: Powering underwater systems is challenging. Relying on batteries limits operational time, while connecting to surface power can be impractical.
4. Data Processing: The large volume of collected data requires advanced processing and bandwidth handling power.
5. Integration with Other Systems: Combining various technologies (e.g., sensors, cameras, autonomous vehicles) into a cohesive system can be complex.
6. Security Concerns: Underwater systems can be vulnerable to cyberattacks, requiring robust security measures to protect sensitive data.
7. Cost: High costs associated with development, deployment, and maintenance can be prohibitive, especially for smaller organizations.

Future Trends in Subsea Surveillance Systems

1. Advanced Sensors: Development of more sensitive and versatile sensors (e.g., multi-spectral imaging, biomimetic sensors) will enhance surveillance capabilities.
2. Autonomous Underwater Vehicles (AUVs): The use of AUVs for surveillance will increase, allowing for more flexible and extensive data collection.
3. Improved Communication Technologies: Advances in optical and acoustic communication technologies will enhance data transfer rates and reliability.
4. Machine Learning and AI: Leveraging AI for data analysis will improve the ability to detect anomalies and automate decision-making processes.
5. Interconnectivity: Greater integration of underwater systems with surface and aerial systems will facilitate comprehensive monitoring and data sharing.
6. Sustainability: Focus on developing eco-friendly materials and energy sources (like ocean thermal energy) to power subsea systems will grow.
7. Real-Time Monitoring: Enhanced real-time data processing capabilities will allow for immediate responses to detected events or changes in the environment.

Conclusion

Subsea surveillance systems are vital for safe and efficient offshore operations. By combining sensors, fiber optics, ROVs, and AI, these systems provide real-time monitoring, leak detection, and predictive maintenance—all controlled from the surface.