Like its sister hospital, Charity Hospital, University Hospital sustained severe flood damage during Hurricane Katrina, and its patients were evacuated by boat and helicopter after the storm. In addition to the flood damage to the structure itself, the significant flooding caused the emergency generators to become submerged (as a result of being on the first floor), eventually becoming inundated with floodwater and failing. Another substantial impact caused by the overwhelming flood waters was the devastation to the sewage system. As those employed by the hospital attempted to successfully care for patients while dealing with limited supplies and manpower, the sewage system eventually failed, exposing all occupants of the hospital to potential diseases and illnesses. However, the hospital was extensively renovated and reopened November 20, 2006.