A505, Hertfordshire Baldock Bypass Tunnel Construction

The original A505 route through the centre of Baldock between Royston and the A1 was a heavy traffic black spot. A new twin bore, dual carriageway tunnel was needed to relieve congestion along the route.

VVB was appointed by main contractor Taylor Woodrow to project manage the Mechanical and Electrical (M&E) requirements of the project, from inception through installation, commissioning and delivering the finished scheme.

VVB’s role in the project included:

• Liaison with civils to produce a complete turnkey solution
• Providing technical knowledge and experience to all elements of the M&E systems.

VVB’s proactive, open approach and transparent design input enabled a reduced M&E installation timescale, and brought the opening date forward eight months ahead of schedule.

Throughout the design and pre‐construction phase of the road and highways project, VVB provided extensive technical knowledge and mechanical and electrical experience.

There were additional complexities for VVB. These included the requirement for SCADA Operational Surveillance and Control by Hertfordshire Police headquarters, and the need to provide maintenance warnings to Hertfordshire Highways. Both were supplied through uplink via BT Redcare.

The full scope included the provision of:

• HV and LV distribution, and a UPS system
• SCADA and PLC control system
• An IP network, radio re‐broadcast, GSM mobile, external communications links and public address
• Tunnel lighting, including control and small power
• Approach road VMS and cross passage doors
• Weather monitoring and pollution sensors
• Emergency telephones, fire main and drainage control
• Spillage containment tank, tunnel LCS and SOS signage
• HVAC, fire detection and fire suppression
• Security and access controls