Me. Rev. Stat. tit. 38, § 1156

A person may enter the person's private sewer into any sewer of a sanitary district formed under this chapter while the same is under construction and before completion of such sewer at the point of entry, on obtaining a permit in writing from the trustees of the district; but after the sewer is completed to the point of entry and an entrance charge established on that location, a person may not enter the person's private sewer into such sewer until the person has paid the entrance charge and obtained a permit in writing from the trustees. All such permits must be recorded by the clerk of the district in its records before the same are issued.