12. For the purposes of Chapter 2 of Part 2 of the Water Resources Act 1991(1) (abstraction and impounding of water) and section 109 of that Act (as to structures in, over or under watercourses) as applying to the construction of any specified work, any consent or approval given or deemed to be given by the Agency under this Schedule with respect to such construction shall be deemed also to constitute a licence under that Chapter to obstruct or impede the flow of inland waters at that point by means of impounding works or, as the case may be, a consent or approval under section 109.