For the purposes of the following enactments, that is to say—
the local authority shall, for any district, be the district council, and for any London borough, be the borough council and for any principal area in Wales, be the principal council.
For the purposes of the following enactments, that is to say—
the local authority shall for any area outside Greater London be the district council.
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An order under section 6 of the Public Health Act 1936 or under subsection (3) above or an order amending any such order may confer on a joint board constituted for the exercise of sewerage functions any of the sewerage functions of the constitutent members and may confer such functions—
Schedule 15 to this Act shall have effect for making amendments and modifications to the enactments relating to water and sewerage.
In this section—
"sewerage functions" means functions under any of the enactments mentioned in subsection (2) above; and
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