Me. Rev. Stat. tit. 30-A, § 3403

After a public drain has been constructed and any person has paid for connecting with it, the municipality shall maintain and keep it in repair to afford sufficient and suitable flow for all drainage entitled to pass through it, but its course may be altered or other sufficient and suitable drains may be substituted in its place. If the municipality does not so maintain and keep it in repair, any person entitled to drainage through it may have an action against the municipality for damages sustained by the municipality's neglect.