Background
The flight had just pushed back from a new terminal at the airport. During preflight and an earlier arrival, the crew discussed a NOTAM that cautioned pilots about a ditch that was not easily visible nor marked. The ditch was located directly across from the new terminal. Despite the discussion, the crew did not see the ditch.
Incident Sequence
After pushback, the crew taxied to a hold point and requested a taxi clearance from ground control. The initial clearance instructed a right turn onto the closest parallel taxiway. However, due to weight considerations, the crew requested a runway change. Ground control then amended the clearance to a right turn onto the outboard parallel taxiway.
The captain reported that while looking at the taxiway diagram, he confused his position with taxiway C4 rather than Spot 4. Subsequently, he taxied the aircraft forward across taxiway C, through the ditch, and made a right turn onto taxiway Bravo.
After encountering the ditch, the crew came to a consensus that there was nothing unusual about the aircraft that would preclude continuing the flight. The flight attendants did not inform the flight crew of the extent of motion experienced in the back of the aircraft, nor did the flight crew inquire. The flight to the intended destination was uneventful.
Aftermath
The damage was discovered later by the oncoming crew. At the time of the incident, the infield area was not lit or marked to illuminate the ditch, and the ditch had no boundary hazard markings. One month prior to this event, another air carrier experienced a similar incident in the same area. Following both incidents, airport operations ordered and placed plastic reflective delineators around the ditch area.