The report, released Wednesday, said the Queen of Coquitlam had to shut down one of its engines because of mechanical trouble during a trip from Horseshoe Bay to Nanaimo last November, and the repairs required the bow propeller to be locked out.
The board said a misunderstanding between the engine room and the bridge over what engines and propellers the captain could use to slow down the ferry led to the crash, which caused damage to the terminal and the ferry.
The report found on Nov. 18, 2011, the Queen of Coquitlam was nearing the end of its voyage to Departure Bay when fuel was observed leaking from the injector of a cylinder in one of the main engines. Efforts to stop the leak weren't successful, so the engine was stopped and two of the clutches were locked out.
The lockout of one of those clutches meant the ordinary method for docking the vessel, known as Mode 2, wasn't available, but that hadn't been communicated to the bridge.
The captain used the alternative method, which he'd done successfully before, but "the vessel had less power to reduce speed and only the stern propeller to manoeuvre with," the report said.
"Incomplete communications between the master (captain) and the (chief engineer) led to a lack of understanding regarding the status of Mode 2 and its availability for docking, thereby compromising the safe docking of the vessel," the report found.
The report also found the vessel has a seven-step procedure to address the shutting down of a main engine and it notes the appropriate clutches should be locked out, but it doesn't say which ones.
"In the absence of specific information regarding the operation of a vessel's critical equipment, the engineering staff may unnecessarily lock out clutches that are available for the manoeuvrability of the vessel," the report said.
The report said B.C. Ferries has since implemented new standard operating procedures for speed reduction.
As well, the corporation has developed contingency plans and drills to slow or stop a ferry in the event of a propulsion failure that hinders the vessel's efforts to slow down while approaching a terminal.
A month after the incident at the Departure Bay terminal, another B.C. Ferry slammed into a loading ramp at the Duke Point terminal, also in Nanaimo, injuring two people and heavily damaging the facility.