Which authorities have the power to halt river traffic?

The authority to halt river traffic is vested in multiple entities, all of which play crucial roles in maintaining safety and order on waterways. The District Commander has jurisdiction over the enforcement of navigational rules and may impose restrictions to ensure safety, especially in emergency situations or when navigational hazards arise.

The Captain of the Port (COTP) is responsible for the safety and security of the marine environment and has the authority to control marine traffic, including halting operations when deemed necessary to protect public safety or respond to emergencies, including accidents or dangerous conditions on the water.

Additionally, the Vessel Traffic Service (VTS) Director oversees the movement of vessels within specific waterways. This role includes issuing advisories and, when necessary, directing traffic to prevent congestion and ensure the safety of all vessels in the area.

Each of these authorities has the mandate to act in the interest of public safety, which is why the correct answer encompasses all of them. Their combined efforts can effectively manage river traffic under various circumstances, ensuring safe passage for everyone involved. This cooperative management system is critical in preventing accidents and maintaining the integrity of navigation in busy waterways.