No member of the board shall be held personally liable on any obligation or liability of any kind or character arising out of the claim that he has failed to carry out any obligation imposed upon the board by this division and the Legislature expressly declares that discretion is vested in the board and the members thereof to determine how and when the various provisions of this division and the projects contemplated in this division with which the board is concerned may best be carried into effect.
Ca. Water Code § 8576