S.D. Codified Laws § 46A-4-68
If there are outstanding bonds of the district or if the district has entered into a contract with the United States as provided in chapters 46A-5 and 46A-6, the board of directors may adopt a resolution to the effect that the board deems it to be for the best interests of the district that the lands mentioned in the petition, or some portion of the lands, should be excluded from the district. The resolution shall describe the lands so that the boundaries of the lands can be readily traced. The holders of any such outstanding bonds may give their consent in writing to the effect that they severally consent that the board may make an order by which the lands mentioned in the resolution may be excluded from the district. If any contract has been made with the United States, the secretary of the interior may assent to the change. The assent may be acknowledged by the holders of the bonds in the same manner and form as required in case of a conveyance of land, except the assent of the secretary of the interior need not be acknowledged. The assent shall be filed with the board and shall be recorded in the minutes of the board. The minutes, or a certified copy of the minutes, are admissible in evidence with the same effect as the assent; but if the assent of the bondholders, and in case of any contract with the United States the assent of the secretary of the interior, is not filed, the board shall deny and dismiss the petition. However, if the resolution authorizing the issuance of the outstanding bonds explicitly provides that no bondholder assent is required for the exclusion of lands from the district or if the resolution provides that the bondholder assent is required only under certain specified conditions, then the terms of the resolution shall prevail and no bondholder assent need be obtained as provided in this section.
SDCL 46A-4-68