NIAGARA FALLS — A tour operator who has been unable to obtain a special permit to run tour buses from a glass building on Rainbow Boulevard known as One Niagara has taken his case to court.

Frank D’Agostino, owner of Cataract Tours on Niagara Falls Boulevard, claims the city has unfairly kept him from getting a permit to operate out of One Niagara, despite allowing three other tour operators to sell sightseeing trips from the building.

The lawsuit, filed May 5 in State Supreme Court, claims the city’s “delays in granting the special permit” will harm Cataract Tours because “it will lose part of its tourist season, which it can never get back.”

The lawsuit is the latest in a series of regulatory issues that have plagued the building at 360 Rainbow Blvd. since a 40-foot hole was dug on the property for a failed underground aquarium proposal. The hole has since been filled, and the first floor of the building now operates as a welcome center for tourists.

Letters between the city and an attorney representing the building’s manager show that city officials in June 2008 declared that the building’s site plan approval was “null and void” because the building did not comply with its site plan conditions.

The city has not revoked a certificate of compliance that allows the building’s first floor to remain open.

But Craig H. Johnson, the city’s corporation counsel, notified attorney James C. Roscetti in a letter dated Jan. 27 that the city would not issue any new permits for the building until the “site plan application and approval process is complete.”

The building’s manager, Frank Parlato Jr., has submitted a new site plan, but it has been deemed incomplete by the city’s Planning Department and has not yet been reviewed by the city’s Planning Board.

Johnson declined to comment on D’Agostino’s lawsuit.

“We’re in the process of reviewing the petition filed by Cataract Tours, and we’ll respond with answering affidavits,” Johnson said.

State Supreme Court Justice Ralph A. Boniello III is scheduled to hear arguments Wednesday morning.

Meanwhile, Boniello authorized Cataract Tours to conduct its tour and sightseeing business from the building until the suit is resolved.

D’Agostino, who owns a Buffalo Avenue auto dealership, ran sightseeing trips from three hotels last year after opening Cataract Tours for its first season. This year, he decided to run all of his tours out of One Niagara.

He said three other tour operators already have permits to run sightseeing businesses from the building and that one was renewed as late as April.

“They’re trying to stop me from doing business, which would be a terrible financial burden,” D’Agostino said.

djgee@buffnews.com