The canal gates are closed at the Harvey Canal, 17th Street Canal and the London Avenue Canal due to Hurricane Ike. With water rising in each of these outfall canals to what the Corps of Engineers refers to as the operational trigger, the Corps has decided to close the gates in order to maintain a safe water level in the canals.
While the gates are closed, the Corps, working closely with New Orleans Sewerage and Water Board, will use the temporary pumps at the canal gates in order to maximize drainage in the city.
The gates at the Orleans Avenue Canal are not closed.
Orleans has a higher safe level of water, says Corps spokesperson Amanda Jones, so they probably wont be closed. They didnt close for Gustav either.