The board may only use for the payment of the acquisition, construction, completion, maintenance, or insurance of any project undertaken under the authority of this chapter, the proceeds of revenue bonds issued and sold by the board, or the revenues from such project.
The following provisions of this section shall only be applicable to projects in counties containing a population of 4,000,000 or more.
If at the beginning of any fiscal year it is estimated that the revenues from the project will be insufficient to meet the bond interest and redemption requirements and the operation and maintenance requirements of any indenture entered into in connection with the issuance of revenue bonds for the project, the board may, by a four-fifths vote, advance an amount of money which, when added to any other funds available for that purpose, will be sufficient to maintain and operate the project for the year. Any such advance shall only be available for expenditure under terms and conditions prescribed by the board and shall be repaid from the first revenues of the project which can legally be made available for that purpose under the revenue bond indenture.
If the board of supervisors determines that any lands within the project are not suitable for revenue-producing use but can be used for public beaches, parks or other facilities for general public nonrevenue-producing use, it may adopt a resolution setting aside specific lands for such use. If the board of supervisors determines that the revenues of the project will be impaired by setting aside any such lands, provision shall be made for monthly payments into the revenue fund of an amount not less than the amount of such impairment, but not to exceed the fair rental value of the land.