For the purposes of any scheme under Schedule 2 to this Act, so much of any sewer as is vested in a water authority immediately before the transfer date but is—
situated in the area of another water authority; and
maintained for the purpose of draining premises in that area,
shall be deemed to have vested in the other water authority before the coming into force of that scheme.
Where any part of a water authority's sewer is deemed by virtue of this section to have vested in another water authority, anything which—
has been done by or in relation to the first-mentioned authority for any purposes connected with that part of that sewer; and
is in force or effective immediately before the transfer date,
shall have effect for the purposes of any transitional provision contained in this Act as if it had been done by or in relation to that other authority.
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