SDCL § 9-19-13: Effective date of resolutions and ordinances--Grounds for immediate effectiveness.

Except as otherwise provided in this section, every resolution or ordinance passed by the governing body takes effect on the twentieth day after its publication, unless suspended by operation of a referendum.

An ordinance or resolution may take effect immediately if it:

(1) Is necessary for the immediate preservation of the public peace, health, safety, or support of the municipal government and its existing institutions;

(2) Is not subject to referendum pursuant to § 9-20-19; or

(3) Provides for an election or hearing on an improvement or assessment or calls for bids.