how did they get rid of the water from hurricane katrina
Drainage in New Orleans On August 31, flood levels started to subside. The water level in the city had reached that of Lake Pontchartrain, and as the lake started to drain back into the Gulf, some water in the city started to flow into the lake via the same levee breaches they had entered through. In 19th century lake floods, the water soon flowed back into the lake as there were no levees on that side. In 2005, while the levees proved inadequate to keep the lake out of the city, even in breached form they were sufficient to keep much of the flooding from flowing back out. As breaches were gradually filled, some city pumps were reactivated, supplemented by additional pumps brought in by the United States Army Corps of Engineers. Some of the city's pumps which survived could not be reactivated because of the failures of the canals that they pumped flood waters into. The combined task of closing breaches and pumping the flood waters out took weeks and was compounded by a setback in late September due to further flooding from Hurricane Rita.
Hurricane Katrina effects by region By August 31, eighty percent (80%) of the city of New Orleans was flooded by Hurricane Katrina, with some parts of the city under 20 feet (6.1 m), of water. Over 50 breaches in region's levee system were catalogued, five of which resulted in massive flooding of New Orleans. The 17th Street Canal levee was just south of the Hammond Highway Bridge. Levees adjacent to London Avenue breached in two locations: one near Robert E. Lee Boulevard and one between Filmore Avenue and Mirabeau Avenue. Two breaches also occurred in the Industrial Canal adjacent to Surekote Road. Levee repair efforts were undertaken, involving reinforcing the levees with 3,000 pounds (1,400 kg) sandbags deployed by U.S. Army Chinook and Black Hawk helicopters. The 17th Street Canal levee repair was completed by September 5, 2005 and subsequently, the three canals were repaired all the way to Lake Pontchartrain. The Army Corps of Engineers added flood gates to the three canals.