Plymouth navigational alert as Breakwater lighthouse and foghorn deemed unreliable

Plymouth King’s Harbour Master issued a navigational warning today (August 7, 2025), revealing that the Breakwater Lighthouse and its accompanying foghorn are currently unreliable due to ongoing maintenance operations.

The lighthouse—an essential aid at the western tip of Plymouth Breakwater—has intermittently faltered, while the foghorn’s signals cannot be depended upon.

This latest advisory, Navwarn 033/25, supersedes an earlier notice from 25 July (Navwarn 032/25), which solely concerned the light being unlit. Mariners navigating Plymouth Sound are urged to exercise heightened caution during this period of diminished navigational assistance.

In 1811 Civil Engineer John Rennie was instructed by the Admiralty to draw up plans for a breakwater that would transform the Sound into 1,000 acres of safe anchorage. The project was referred to as 'the great national undertaking' when work started the following year - and took almost 30 years to complete.