Each year’s income credited to the permanent reservoirs for irrigation purposes income fund and the improvement of Rio Grande income fund may be pledged irrevocably to the payment of the principal of and interest on revenue bonds by the commission with the approval of the state board of finance, and there are irrevocably appropriated to the commission amounts from the funds for such purposes. The commission shall provide in the proceedings authorizing the issuance of each series of bonds for the paying into the appropriate income and debt service funds all money received pursuant to this section.