Whenever revenue bonds are issued hereunder, it shall be the duty of the board to impose, in connection with the project for which the bonds are issued, for the services rendered or facilities furnished thereby, tolls, fees, rates, rentals and charges fully sufficient to pay the cost of operating and maintaining the project, including but not limited to betterments or replacements to keep the same in good repair and working order (which cost shall be a first lien and charge upon the revenues or income to be derived from the operation of the project or service), and to pay the principal of and interest on the bonds, and to carry out all commitments made in the resolution or resolutions authorizing the bonds.
W.S. 41-10-143