This time, two staff members were taken to hospital and the CityCat, Yarragarra, "smashed in" its front hull when it struck the New Farm Sydney Street terminal.

A regular daily passenger, who asked not be named, said two people were taken to hospital after the CityCat ploughed into the Sydney Street wharf.

"It was coming upstream about 11.09am," the passenger said.

"It was coming into Sydney Street there at New Farm.

"Something happened to it and it just ploughed into the wharf. That's twice in a fortnight. It makes you wonder if they are safe to travel on."

The Queensland Ambulance Service confirmed it took a patient from the Sydney Street CityCat wharf to St Andrew's War Memorial Hospital at 11.16am.

"That was after a fall and the patient is in a stable condition," the QAS spokeswoman said.

The passenger said he was waiting to catch a ferry travelling in the opposite direction. He said he believed two staff members were taken to hospital.

"The ambulance came along and they took the ticket-seller off to hospital by ambulance and the deckhand, he was also hurt," he said.

"They took him away but I'm not sure if they took him away in a private car. He didn't go by ambulance but they took him away (to hospital) as well."

The QAS said it did not take a second person to hospital and did not know if a second person was admitted privately.

On January 4, CityCat commuters were "shaken and bruised" when the boat collided with the Riverside Centre terminal at Eagle Point.

The CityCat fleet is run by the company Transdev for the council.

Brisbane City Council said there was no damage to the CityCat or the terminal. It was advised one CityCat worker was taken to hospital.

There were no obvious signs of damage at the terminal on Monday afternoon and staff advised the ticket-seller was released from hospital on Monday after checks.  The CityCat was not at the terminal.

Transdev was contacted for comment.