The board may, by resolution, order that any of the monies in the funds under its control which are not necessary for current operating expenses be invested in any obligation, bonds or securities in which a city or county could invest such funds, provided that:
1. Any such investment shall be made in such a manner that the monies in such funds will be available at the times and in the amounts necessary to accomplish the purpose for which such funds were established.2. No such investment shall be made in contravention of any provision or covenant in any proceedings for the authorization and issuance of bonds, notes, contracts or other evidences of indebtedness.