§9–721.

    (a)    The powers granted to political subdivisions by Part III of this subtitle are supplementary to any other powers of the political subdivisions.

    (b)    This section does not:

        (1)    Invalidate any procedures initiated or completed by any political subdivision before June 1, 1972; or

        (2)    Limit or modify any provision of any general or local law effective before June 1, 1972.