KiwiRail admits it failed to identify problems with a crossing in Auckland where a disabled woman was critically injured.
The woman's wheelchair was stuck in the tracks at the Morningside station in February this year and she was dragged along by a freight train.
KiwiRail on Wednesday issued its report on the incident, saying the degraded condition of the crossing was not identified and remedied as it should have been.
Chief executive Jim Quinn has apologised for the failure and said improvements have been made.
The company said no other crossings have been found to have the same level of risk, but work has been done on 60 others throughout Auckland to improve their evenness underfoot.
The mother of the injured woman says the family has seen the report and are happy with the findings. She says her daughter is in a rehabilitation unit and her condition is improving.
Listen to Checkpoint interview with Jim Quinn