What function do lateral buoys serve in maritime navigation?

Lateral buoys play a crucial role in maritime navigation by designating channel edges. They are part of the IALA (International Association of Lighthouse Authorities) buoyage system, which aims to provide mariners with clear and consistent visual signals of navigational hazards and safe passage. These buoys are typically placed along the sides of navigable channels to indicate the limits of safe water.

For example, in the IALA system, red buoys mark the port side of a channel when entering from the sea, while green buoys mark the starboard side. This color coding helps vessels maintain a safe course through the channel, reducing the risk of grounding or collision with underwater obstacles. It is essential for navigation, especially in narrow or congested waterways where precise knowledge of channel boundaries is critical for safe passage.