Query: As president, Obama will immediately close the Mississippi River Gulf Outlet, which experts say funneled floodwater into New Orleans.

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Hurricane Katrina <=SEP=> Hurricane Katrina was the costliest natural disaster and one of the five deadliest hurricanes in the history of the United States . The storm is currently ranked as the third most intense United States landfalling tropical cyclone , behind only the 1935 Labor Day hurricane and Hurricane Camille in 1969 . Overall , at least 1,245 people died in the hurricane and subsequent floods , making it the deadliest United States hurricane since the 1928 Okeechobee hurricane . Total property damage was estimated at $ 108 billion ( 2005 USD ) , roughly four times the damage wrought by Hurricane Andrew in 1992 in the United States .   The eleventh named storm and fifth hurricane of the 2005 Atlantic hurricane season , Katrina originated over the Bahamas on August 23 from the interaction between a tropical wave and the remnants of Tropical Depression Ten . Early the following day , the new depression intensified into Tropical Storm Katrina . The cyclone headed generally westward toward Florida and strengthened into a hurricane only two hours before making landfall at Hallandale Beach and Aventura on August 25 . After very briefly weakening to a tropical storm , Katrina emerged into the Gulf of Mexico on August 26 and began to rapidly deepen . The storm strengthened to a Category 5 hurricane over the warm waters of the Gulf of Mexico , but weakened before making its second landfall as a Category 3 hurricane on August 29 in southeast Louisiana .   The storm caused severe destruction along the Gulf coast from central Florida to Texas , much of it due to the storm surge and levee failure . Severe property damage occurred in coastal areas , such as Mississippi beachfront towns ; over 90 percent of these were flooded . Boats and casino barges rammed buildings , pushing cars and houses inland ; water reached 6 - from the beach .   Over fifty breaches in New Orleans 's hurricane surge protection were the cause of the majority of the death and destruction during Katrina on August 29 , 2005 . Eventually 80 % of the city and large tracts of neighboring parishes became flooded , and the floodwaters lingered for weeks . According to a modeling exercise conducted by the U.S. Army Corps of Engineers ( USACE ) , two-thirds of the deaths in Greater New Orleans were due to levee and floodwall failure . All of the major studies concluded that the USACE , the designers and builders of the levee system as mandated by the Flood Control Act of 1965 , is responsible . This is mainly due to a decision to use shorter steel sheet pilings in an effort to save money . In January 2008 , Judge Stanwood Duval , U.S. District Court , ruled that despite the Corps ' role in the flooding , the agency could not be held financially liable because of sovereign immunity in the Flood Control Act of 1928 . Exactly ten years after Katrina , J. David Rogers , lead author of a new report in the official journal of the World Water Council concluded that the flooding during Katrina `` could have been prevented had the corps retained an external review board to double-check its flood-wall designs . ''   There was also an investigation of the responses from federal , state and local governments , resulting in the resignation of Federal Emergency Management Agency ( FEMA ) director Michael D. Brown , and of New Orleans Police Department ( NOPD ) Superintendent Eddie Compass . Many other government officials were criticized for their responses , especially New Orleans Mayor Ray Nagin , Louisiana Governor Kathleen Blanco , and President George W. Bush . Several agencies including the United States Coast Guard ( USCG ) , National Hurricane Center ( NHC ) , and National Weather Service ( NWS ) were commended for their actions . They provided accurate hurricane weather tracking forecasts with sufficient lead time .

Mississippi River–Gulf Outlet Canal <=SEP=> The Mississippi River -- Gulf Outlet Canal ( abbreviated as MRGO or MR-GO ) is a 76 mi channel constructed by the United States Army Corps of Engineers at the direction of Congress in the mid-20th century that provided a shorter route between the Gulf of Mexico and New Orleans ' inner harbor Industrial Canal via the Intracoastal Waterway . In 2005 , although disputed by the Corps of Engineers , the MRGO channeled Hurricane Katrina 's storm surge into the heart of Greater New Orleans , contributing significantly to the subsequent multiple engineering failures experienced by the region 's hurricane protection network . In the aftermath the channel was closed . A permanent storm surge barrier was constructed in the MRGO in 2009 , and the channel has been closed to maritime shipping .   The MRGO begins just east of I-510 's crossing of the Gulf Intracoastal Waterway in New Orleans East and takes a path SSE through St. Bernard Parish wetlands just west of Lake Borgne to the Gulf of Mexico near Gardner Island . Much criticized for its negative environmental effects , such as saltwater intrusion , wetlands erosion and storm surge amplification during Hurricane Katrina , the MRGO was closed in 2009 . Maritime traffic was barred on April 22 , 2009 .

Hurricane Gustav <=SEP=> Hurricane Gustav ( -LSB- ˈɡʊstɑːv -RSB- ) was the second most destructive hurricane of the 2008 Atlantic hurricane season . The seventh tropical cyclone , third hurricane , and second major hurricane of the season , Gustav caused serious damage and casualties in Haiti , the Dominican Republic , Jamaica , the Cayman Islands , Cuba and the United States . Gustav caused at least $ 6.6 billion ( 2008 USD ) in damages .   It formed on the morning of August 25 , 2008 , about 260 mi southeast of Port-au-Prince , Haiti , and rapidly strengthened into a tropical storm that afternoon and into a hurricane early on August 26 . Later that day it made landfall near the Haitian town of Jacmel . It inundated Jamaica and ravaged Western Cuba and then steadily moved across the Gulf of Mexico .   Once into the Gulf , Gustav gradually weakened because of increased wind shear and dry air . It weakened to a Category 2 hurricane late on August 31 , and remained at that intensity until landfall on the morning of September 1 near Cocodrie , Louisiana . Weakening continued , and Gustav weakened to a tropical storm that evening and to a tropical depression the next day as it meandered around the south-central US . The weak system became extratropical on September 4 and was absorbed by another low on September 5 .   In total , an estimated 153 deaths had been attributed to Gustav in the U.S. and Caribbean . Damage in the U.S. totaled to $ 4.3 billion ( 2008 USD ) with additional damage of $ 2.1 billion in Cuba and $ 210 million in damage in Jamaica .