(a) The powers granted and duties prescribed by this chapter are subject to all legislative declarations of public policy in the maximum use of the storm water, floodwater, and unappropriated flow water of the basin for the purposes for which the authority is created.
(b) The commission shall consider the adequacy of, and approve or refuse to approve, any flood control or conservation improvement plan that:
(1) is devised by the authority to achieve a plan or purpose for which the authority was created; and
(2) contemplates improvements that are to be supervised by the commission under general law.