The Helford River is a voluntary marine conservation area. Close in to Durgan and Grebe beach the sea bed is covered in Sea Grass, there is a no anchoring area off of Grebe Beach to protect the Sea Grass. During spring, Thornback Rays move in en-mass to breed, you will find it hard to avoid them, they are always a few around. In the mouth of the Helford is the wreck of the Rock Island Bridge and further up stream towards the Helford Passage the Duchy Oyster Farm keep their Pacific Oyster growing cages. The river bed changes from area to area, north to south. The sea bed is made up from some soft sand, coarse sand, empty shells and some with pebbles. The mixture of sea bed substrates and currents, creates a home with lots of food, for a wide variety of marine life. The river is an ideal dive site for the wildlife photographer or marine biologist. After a dive in the VMCA, Monty Halls stated “As a marine biologist, you couldn’t have put me anywhere better”.
Although the area is well known for it’s scallop beds, the Helford river itself is a PRIVATE FISHERY, removing scallops from the river is a criminal offence i.e. stealing. Without permission from the Duchy, no scallops should be removed.
Most of the river is quite shallow apart from the Helford Pool between the Helford Passage and Helford village, The Helford Pool and the Rock Island Bridge are classed as separate dives from the VMCA, although you can do the Rock Island Bridge and part of the VMCA or the Helford Pool and part of the VMCA on the same dive.