Meetings shall be held at the call of the chairman or whenever two commissioners so request. Four commissioners of the authority shall constitute a quorum and any action taken by the authority under the provisions of this chapter may be authorized by resolution approved by a majority but not less than four of the commissioners present at any regular or special meeting. No vacancy in the membership of the authority shall impair the right of a quorum to exercise all the rights and perform all the duties of the authority.
SDCL 11-11-19