(a) No money shall be allocated to any water district for any fiscal year pursuant to this article, unless the Legislature approves such allocation for that fiscal year pursuant to this section by appropriating the money from the Motor Vehicle Transportation Tax Fund for such purpose.
(b) In case the amount of money appropriated by the Legislature for purposes of this article during any fiscal year is insufficient to pay the amounts provided for in Section 831, the amounts provided for in that section shall be reduced proportionately.