It shall be unlawful for the officers of any county, unless specially and expressly authorized by law, to contract any debt or incur any pecuniary liability, unless both the principal and annual interest thereof, in addition to other necessary disbursements, can be paid by the levy for the current year on the taxable property within the county at not exceeding the maximum rate prescribed by law; or in case such levy for the current year has been made, then by levy for the next subsequent year at not exceeding such maximum rate.
SDCL 7-21-16