7. Should any accumulation or erosion in consequence of such construction arise within the period of 10 years mentioned in paragraph 6 and be remedied in accordance with paragraph 8, any recurrence of such accumulation or erosion shall from time to time be so remedied by the Council during that period of 10 years and at any time thereafter, save that the Council’s obligation under this paragraph shall cease in the event that following the remedying of any accumulation or erosion a period of 10 years elapses from the completion of that remedying, without any further accumulation or erosion being caused or created in consequence of such construction or exercise.