JOHNSTOWN — Canada Lake property owner Joseph Herms must demolish his lakeside structure in the next eight months, pay a $50,000 civil penalty to the town of Caroga and pay the town’s court costs, acting Supreme Court Judge Richard C. Giardino ordered Monday.

Giardino, in a 25-page decision, ruled that after the town repeatedly denied Herms a permit to build a lakeside house in the late 1990s, he went ahead and built it anyway under the guise of a boathouse.

The project has been the subject of litigation in both state and federal courts for nearly a decade. Giardino’s decision follows a trial in Supreme Court in Fulton County that began last November and concluded over the winter.

The town’s lawyer, Salvatore D. Ferlazzo of the Albany firm of Girvin & Ferlazzo, said he anticipates Herms and his attorney, Sheila Galvin, will appeal to the Appellate Division of State Supreme Court but expressed confidence that Giardino’s decision will be upheld.

“I consider this matter done,” Ferlazzo said. He estimated the town’s court costs at several thousand dollars.

Galvin could not be reached for comment.