The boundaries of a drainage district may be extended upon compliance with the requirements and procedures as follows:
Should the area proposed to be included within the boundary of the enlarged district embrace one or more existing drainage districts, the commissioners of any such district or districts may join in a petition to the court asking for the extension of boundaries of the existing district.
The joinder in the petition by the commissioners of such drainage district in the name of the district shall have the effect of including in the petition all of the land within said existing drainage district to the same extent as if the petition had been signed individually by each landowner of the district. The total acreage in such district or districts shall be included as land in the petition in determining whether or not the requirements under this section have been complied with.
The filing of a certificate by the attorney for, or the commissioners of, the district that due diligence has been used to notify each of said defendant landowners shown by the report of the board of viewers, either by personal service or by publication, shall be sufficient showing of compliance with this provision. The certificate shall contain the names of such landowners served personally, the date of service and the names of those served by publication and the date of service by publication.
If the clerk shall determine that all of the three preceding requirements are met, he shall direct that the area(s) of land to be included within the boundaries of the district, in accordance with the provisions of the report of the board of viewers, as approved.
N.C. Gen. Stat. § 156-93.3