Operations and Maintenance

Internationally, there exists a variety of underground transportation management models and practices that would be evaluated for potential adaptation and application for the Cross Sound Link Tunnel. System elements that would be studied include operation and maintenance systems for traffic management, environmental control, communications, incident and emergency response, safety and security. The Cross Sound Link Tunnel would benefit from past endeavors to create a state-of-the-art transportation system.

Tolling Services

In order to facilitate smooth transitions into the tunnels, access would likely be permitted on the basis of automated tolling only. The south portal would be the more favorable location for a toll plaza serving both directions of traffic. The north portal would be less desirable due to the complexity of ramp configurations required to link the north portal with a revamped I-95/I-287 interchange.

Control Center

A Control Center that housed control facilities, such as closed-circuit cameras and emergency response equipment, would be located near one of the tunnel portals, probably adjacent to the toll plaza at the south portal. These facilities would consist of a control room, an emergency response center, a main office and security accommodations.

A backup control center to the main Control Center could be located at the other end of the tunnel.

Infrastructure Equipment

All major mechanical, electrical and plumbing equipment would be housed within the limits of the tunnel right of way or within dedicated spaces in the service tunnel. Bulky equipment such as substations or fan plants would be designed and constructed in a manner that would be least intrusive to the environment.

Service Tunnel

The service tunnel would be used for emergency response and evacuation purposes as well as ventilation and utility services. For emergency response, the central service tunnel would be equipped with a dedicated service roadway suitable for high-speed running of service and emergency vehicles. Applying proven practices of other tunnel transportation management systems, the service vehicles would likely be specially designed vehicles with an operator cab at each end. They could be steered manually or automatically by wire guidance, at speeds up to 50 mph. Other vehicles could also be used with diesel or electric propulsion.

Emergency Response Measures

Emergency facilities would be provided at each end of the tunnel to minimize the response time in the event of an incident. These facilities would include garage space for emergency vehicles.

Trained tunnel staff, stationed at each end of the tunnel, could provide the first line of response (FLOR) until off-site emergency services arrived. This is common practice for many road tunnels with permanent staff. In addition, a small emergency response team could be stationed in the central service tunnel at the tunnel mid-point to further reduce the response time for incidents in the central portion of the tunnel. All staff would be trained in emergency response procedures and full-scale exercises would be carried out annually. Such exercises could involve temporary or partial closure of the tunnel.

Close liaison with emergency authorities throughout the tunnel design process would be necessary to ensure that their requirements are met and that they are able to prepare for the challenge of providing emergency cover for such a major project at all stages.