Such bonds shall be issued serially and the last of them shall mature not more than forty years from the date of issue, to bear a rate of interest not to exceed six percent per annum payable semiannually at some place in the State or the office of some banking or trust company in the city of New York to be selected by the commissioners. The amount of the bonds to be issued shall be determined by the commissioners of the districts.
S.C. Code § 6-11-190