Notwithstanding any other provision of law any person who represents a municipal water district on the board of directors of any metropolitan water district formed pursuant to the Metropolitan Water District Act may receive compensation and expenses from the municipal water district with respect to service on such board of directors of a metropolitan water district, in the same amount, and upon the same terms, as shall be provided with respect to service on the board of the district. Any compensation or expenses received pursuant to this section shall be in addition to that provided in Section 71255.