Benacre Broad is a very fragile strip of brackish water separated by a narrow sand/shingle beach. I haven't been here for just over a year but on my last visit as the above pics show that the broad has been breached by the ever encroaching sea.
The strip North to Kessingland and South all the way to Southwold is under extreme pressure from erosion. This area is managed by English Nature, Terns and Ringed Plovers can be seen nesting on the beach in the summer where parts are roped off to protect their nests. There is a bird hide overlooking the Broad [warning this is accessible by steep wooden steps and the sea can sometimes surround the base of the steps] which is situated at the Covehithe end of the Broad.
Also be aware that the cliffs between Covehithe and Benacre are very crumbly with access to the beach only available at Benacre.
Marsh Harriers, Bitterns and Egrets frequent the area as do many other waders and wildfowl.
More debris on the beach as seen from the clifftops, to the centre left of the picture is Southwold Pier and beyond that is Sizewell B Nuclear Power Plant, probably some 10 miles away