Sts. & Hy. Code, § 30305

From the money deposited in each separate acquisition and construction fund, the State Treasurer shall transfer to the place or places of payment named in the bonds such sums as are required to pay the interest as it becomes due on all bonds sold and outstanding for the construction of the particular toll bridge or other highway crossing, transportation facilities, or additional transportation facilities during the period of actual construction and during the period of six months immediately thereafter. The treasurer shall thereafter transfer from each separate toll revenue fund to the place or places of payment named in the bonds such sums as are required to pay the interest on the bonds and to redeem the principal thereof as such interest payments and bond redemptions fall due for all bonds issued and sold for the construction or acquisition of the particular toll bridge or other highway crossing, transportation facilities, or additional transportation facilities producing the tolls or revenues deposited in the toll revenue fund. All funds transferred for the payment of principal or interest on bonds issued for any particular toll bridge or other highway crossing, transportation facilities, or additional transportation facilities shall be segregated and applied solely for the payment of such principal and interest.