In districts which are following the alternative method of collecting assessments, as provided for by § 46A-7-22, a single assessment, to include operation and maintenance funds and contract funds, may be made, and such assessment so levied shall become due and payable on January first next following the levy of such assessment, and become delinquent if not paid in full on or before May first following such assessment and shall draw interest and penalty as provided in § 46A-7-19.
SDCL 46A-7-25