The said board shall have full power to do any and all things required by the federal statutes now or hereafter enacted in connection with such contracts, and all things required by the rules and regulations now or that may hereafter be established by any department of the federal government in regard thereto; and in the purchase of any property or property rights, or in acquiring or contracting for the water supply of the district, the bonds of the district may be used by the board at not less than ninety per cent (90%) of their par value, in payment.