The Chehalis basin account is created in the state treasury. All receipts from direct appropriations from the legislature, including the proceeds of tax exempt bonds, or moneys directed to the account from any other sources 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 bonds.