Seagrass monitoring survey and seabed mapping will take place in Dale Bay from 14th–18th September 2025 by RV Gwenhidw and USV Blueboat.

  1. MARINERS ARE HEREBY ADVISED that diving operations to conduct seagrass surveys and seabed mapping will be undertaken in Dale Bay at position 51°42'17.6"N 005°09'34.9"W from 14th to 18th September 2025 (see below chart with operational area) carried out by ‘Project Seagrass Ltd’.
  2. Diving operations will be carried out by the vessel ‘’ RV Gwenhidw‘’, with transect lines marked by small orange buoys and USV Blueboat(1m long and remotely operated ) will conduct seabed mapping.
  3. RV Gwenhidw will display lights and shapes in accordance with COLREGS, Flag A will be displayed whenever divers are in the water. Vessel will remain in contact with Milford Haven VTS and always  monitor VHF Ch. 12.      
  4. Mariners are requested to navigate with caution, pass at a safe speed, and maintain a safe distance when operating in the area.
  5. Admiralty Charts 3274, 3275, IMRAY Y26, and 2600 Atlas refer.
  6. This Notice to Mariners will self-cancel at 23:59 on 18th Sept 2025.

BY ORDER
M RYAN
HARBOURMASTER

Port of Milford Haven
Gorsewood Drive
Hakin
Milford Haven
Pembrokeshire
SA73 3EP

Tel: 01646 696100
Email: enquiries@mhpa.co.uk