Wyo. Stat. § 41-7-101: Waiver of defect of service.

In case of failure to serve any notice of any proceeding or hearing in this chapter provided for upon any person or corporation, such persons or corporation may appear in open court and waive such defect of service, or may waive it by filing in court or delivering to the commissioners of the irrigation district to be filed in court a written waiver of such defect, in which waiver said defect shall be described, which waiver shall be signed by such party and witnessed and acknowledged before a proper officer having power to take acknowledgments of deeds.