At least three clusters of rocks block the approach to the north side of LBC's beach. All boats should avoid this side at low tide, and sailboats with daggerboards should avoid it at all times.
The approximate location of the rocks is indicated in orange in the Google Maps image below. The safest approach to the beach is indicated by the green arrow: approach from the direction of the ferry terminal.
The farthest cluster of rocks from the beach is marked by a white buoy (however, the buoy sometimes slips away from the proper location). One large patch of rocks is almost immediately opposite the aisle from the 2nd and 3rd rows down to the water.
The photograph below (courtesy of Bob Wilson) shows the rough location of the three patches of rocks at very low tide. The photo was taken standing slightly to the south of the aisle between the rows of sailboats.