Larger, heavily used tunnels, such as the Big Dig tunnel in Boston, Massachusetts, may have a dedicated 24-hour staffed operations center which monitors and reports on traffic conditions, and responds to emergencies. Video surveillance equipment is often used, and real-time pictures of traffic conditions for some highways may be viewable by the general public via the Internet.
Larger, heavily used tunnels such as the Big Dig tunnel in Boston, Massachusetts, may have a dedicated 24-hour staffed operations center which monitors and reports on traffic conditions, and responds to emergencies. Video surveillance equipment, is often used, and real-time pictures of traffic conditions for some highways may be viewable by the general public via the Internet.