Efforts to protect a section of coastline near Sidmouth have been hampered by recent stormy weather.
Cliffs at Pennington Point were to be shored up with shingle dredged from the River Sid.
But the shingle, left on the beach prior to being moved, has been washed away by high tides and bad weather.
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Sergei Skripal and police officer Nick Bailey will reportedly be compensated after their houses were contaminated in the March 4 nerve agent
A teenage boy is also in hospital. Police believe both had suffered adverse reactions to an unknown substance.
Sunshine all day tomorrow and warm week ahead