The Chehalis basin taxable account is created in the state treasury. All receipts from the proceeds of taxable bonds for the office of Chehalis basin, as well as other moneys directed to the account, must be deposited in the account. Interest earned by deposits in the account will be retained in the account. Moneys in the account may be spent only after appropriation. Expenditures from the account may be used only for the purposes set out in RCW 43.21A.730 and for the payment of expenses incurred in the issuance and sale of the bonds.