law: Indian Easements Act, 1882
  44. Extinction on permanent alteration of servant heritage
  
  by superior force 
  An easements is extinguished where the servant heritage is by
  
  superior force so permanently altered that dominant owner can no longer enjoy
  
  such easement:
  PROVIDED that, where a way of necessity is destroyed by
  
  superior force, the dominant owner has a right to another way over the servant
  
  heritage; and the provisions of section 14 apply to such way.
  Illustrations
  (a) A grants to B, as the owner of a certain house, a right to
  
  fish in a river running through A’s land. The river changes its course
  
  permanently and runs through C’s land. B’s easements is extinguished.
  (b) Access to a path over which A has a right of way is
  
  permanently cut off by an earthquake. A’s right is extinguished.