Client: Decentralized Administration of Crete

The planning for the Crete motorway, VOAK, is progressing steadily, with operations expected to begin in the east before moving to the west. This large project, which has a total budget exceeding 1.7 billion euros, is currently in an advanced phase. Part of the planned works for VOAK includes the upgrade of the Traffic Management and Tunnel Management systems for the Stalida Tunnel, located on the Crete Peninsula near Heraklion. The tunnel is approximately 400 meters long and features one tube accommodating two directions of traffic.

Asset under management:

• Tunnel Lighting Management: The SCADA system monitors the tunnel's lighting, ensuring optimal illumination levels for safe navigation.
• Traffic Signaling Coordination: The SCADA system manages traffic signals, directional indicators, and other visual cues to effectively guide drivers through the tunnel. Modern SCADA systems integrate IoT technologies, enhancing safety and enabling real-time monitoring through Human-Machine Interface (HMI) applications.
  
• Emergency Telephone Monitoring: The system verifies the functionality of emergency telephones, which are essential for user safety during unforeseen events.
• Fire Safety Integration: SCADA integrates fire detection systems, sprinklers, and emergency exits, promptly alerting operators in the event of fire-related anomalies.
• Substation and Pump Station Supervision: SCADA monitors both the substation and pump station, ensuring a stable power supply and efficient water drainage within the tunnel.
• Brightness Measurement: Continuous assessment of brightness levels allows for adaptation to changing external conditions.
• Air Quality Monitoring: Detecting pollutants or hazardous gases enables timely corrective actions to be taken.
• Vehicle Height Control: SCADA prevents collisions in low-clearance areas by verifying vehicle heights.

The need

Road infrastructure, a vital component of modern society, requires periodic upgrades to ensure safety, efficiency, and sustainability. These upgrades accommodate technological advancements, enhance safety features, optimize traffic flow, address environmental impacts, and contribute to economic growth. Regular maintenance is essential for maintaining a resilient and future-ready transportation network.

Upgrading Stalida tunnel traffic management system was critical necessity for Decentralized Administration of Crete. The existing system had become obsolete, lacking compatibility with modern technologies and protocols, which prevented it from supporting new features and standards essential for enhancing safety, efficiency, and user experience. Additionally, its security measures were inadequate, leaving the tunnel vulnerable to cyber threats and unauthorized access. By transitioning to a modern system, we addressed these challenges, improved reliability, and ensured compliance with evolving regulations for critical transportation infrastructure.

Key Technical Features

System Overview: Aveva Edge 2020 Studio software serves as the backbone of the tunnel’s supervisory control system, facilitating interaction between the control center operator and the underlying automation infrastructure. The supervisory control software operates on a server-type PC equipped with the Windows Server 2022 operating system.

The backbone infrastructure consists of Schneider Electric Modicon PLCs, along with the relevant I/O expansion cards and Ethernet switches. All communication between the installed TMS/SCADA in the control room and the field devices is conducted over Modbus TCP.
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‍User Interaction: Most interactions occur through graphical forms using a computer mouse, while keyboard input is limited to specific scenarios, such as entering values or operator data. Operators can perform all routine tasks, except for adjusting certain control system parameters (as detailed in subsequent chapters). Supervisors have unrestricted access to all system operations. The central interface features a fixed frame and a dynamic frame that displays critical screens, including the tunnel layout plan and an alarming list.
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