(a) The board has general jurisdiction over:
(1) the development and implementation of a statewide water plan;
(2) the administration of the state's various water assistance and financing programs including those created by the constitution;
(3) the administration of the National Flood Insurance Program; and
(4) other areas specifically assigned to the board by this code or other law.
(b) The board has only those powers and duties previously delegated by law to the Texas Department of Water Resources that are specifically delegated to the board under this code and other laws of this state.