APPENDIX F: LOOKING BACK Appendix F: Looking Back
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New Orleans Systems Independent Levee Hurricane Katrina Investigation Team July 31, 2006 APPENDIX F: LOOKING BACK Appendix F: Looking Back We must expect more catastrophes like Hurricane Katrina - and possibly even worse. In fact, we will have compounded the tragedy if we fail to learn the lessons - good and bad - it has taught us and strengthen our system of preparedness and response. We cannot undo the mistakes of the past, but there is much we can do to learn from them and to be better prepared for the future. This is our duty. Frances Gragos Townsend Assistant to the President for Homeland Security and Counterterrorism The Federal Response to Hurricane Katrina, Lessons Learned Report to the President of the United States, February 2006 F.1 Synopsis of History of the New Orleans Flood Defense System 1965 - 2005 This synopsis of the history of the New Orleans Flood Defense System (NOFDS) starts in 1965 in the period following hurricane Betsy. This is only the most recent phase in a history of the NOFDS that dates back 300 hundred years. September 1965: Hurricane Betsy sweeps over New Orleans with winds exceeding 100 miles per hour and tides up to 16 feet above mean sea level. Betsy was the most destructive hurricane on record to strike the Louisiana coast. It inundated an area of some 4,800 square miles, killed 81 persons within the state, caused about 250,000 people to be evacuated and disrupted transportation, communication, and utility service throughout the eastern coastal area of Louisiana for many months. East New Orleans, St. Bernard Parish, and the Lower Ninth Ward were particularly hard hit. Residents blamed flooding on the Mississippi River Gulf Outlet (MR-GO, completed 1961) and its connection to the Gulf Inter- Coastal Water Way (GIWW) and the Industrial Canal (Inner Harbor Navigation Canal, IHNC). Earlier in the year, the Orleans Levee Board began driving sheet pilings on the 17th Street canal and other drainage canal levees that had been raised following flooding caused by a hurricane in 1947. Maintenance dredging was initiated by the Corps of Engineers on the MR-GO. October 1965: Congress authorized the Corps of Engineers plan to strengthen the NOFDS to protect from flooding caused by a storm surge or rainfall associated with a Standard Project Hurricane (SPH, estimated to have a 200 to 300 year return period), which is roughly the same as what is now classified as a fast moving Category 3 hurricane. The Corps proposed massive floodgates and barriers on the far end of Lake Pontchartrain to stop hurricane surges from the Gulf of Mexico (Barrier Plan). Also included were additional protection to areas around the lake in the parishes of Orleans, Jefferson, St. Bernard, and St. F - 1 New Orleans Systems Independent Levee Hurricane Katrina Investigation Team July 31, 2006 Charles. This protection included a series of levees along the lakefront and concrete floodwalls along the Inner Harbor Navigation Canal. This plan was selected over another alternative, known as the High Level Plan which excluded the barriers and flood gates and instead employed higher levees. The Barrier Plan was favored because it was believed to be much less expensive and quicker to construct. Although federally authorized, it was a joint federal, state, and local effort with the federal government paying 70 percent of the costs and the state and local agencies paying 30 percent. The Corps was responsible for project design and construction. State and local interests were responsible for operations and maintenance of the flood controls. The project was forecast to take about 13 years to complete (1978) and cost about $85 million. October 1968: The Corps of Engineers performed field tests of levee construction in the Atchafalaya Basin. These test sections were built in 1964 and 1965 to investigate the performance of new levee designs. The sections were instrumented and their performance monitored during and after construction. Important information was developed regarding characterizations of the soil properties and how these should be used in analyzing levee stability factors of safety. Definitive differences were found between soil strengths near the centers and at the toes of the levee test sections. Differences in factors of safety due to different analysis methods were analyzed and it was noted that the method used at that point in time by the Corps of Engineers tended to over-predict the overall factors of safety. August 1969: Construction of floodwalls along the Inner Harbor Navigation Canal, started in 1966, was almost completed as was an earthen levee elevated to 12 feet along Lakeshore Drive from West End Boulevard to the Inner Harbor Navigation Canal when hurricane Camille surge conditions produced similar surge conditions to those of hurricane Betsy. Temporary sheet piling had been driven by the Orleans Levee Board to increase their effective height. Only minor flooding occurred in the project area. Hurricane Camille (Category 5 hurricane) crossed the Mississippi coast at Pass Christian and devastated the coastal communities along the Mississippi coast to Biloxi Alabama. November 1969: Corps of Engineers issues report on Standard Project Hurricane surge and wave conditions for St. Bernard Parish. Effects of MR-GO and its adjacent levee are incorporated into these conditions. December 1973: In order to accelerate construction, the Orleans Levee board financed and constructed portions of the floodwalls along the Inner Harbor Navigation Canal and these were virtually completed at this time. August 1976: Corps of Engineers estimate that he cost of the improved NOFDS had risen to $352 million, and its completion delayed to 1991. In a review of progress, the Comptroller General’s Report to the Congress (1976) observed: “…its (Corps of Engineers) own belated completion of design, plans, and specifications, has contributed to the delays.” The Citrus Back Levee, Michoud Slip Levee, New Orleans East Back Levee, New Orleans East South Point to Gulf Intercoastal Water Way were substantially completed as was the flood protection structure at Bayou Bienvenue. December 1977: In reaction to a suit brought by a coalition of local fishermen and the Save Our Wetlands environmental group in 1976, the Fifth Federal District Court ruled the Environmental Impact Statement for the Corp’s Barrier Plan was inadequate and enjoined construction of the entire project. The Court ordered the Corps of Engineers to produce an F - 2 New Orleans Systems Independent Levee Hurricane Katrina Investigation Team July 31, 2006 environmental impact report on the proposed Barrier Plan. The injunction was subsequently modified to permit construction of the levee and floodwall elements of the hurricane protection plan. September 1979: NOAA issues official revisions to Standard Project Hurricane guidelines first issued during 1959 and used as a basis for the authorization of the Lake Pontchartrain and Vicinity congressional authorization. These revised SPH guidelines increased the sustained and maximum wind speeds, and modified the hurricane radius to the maximum winds and forward speeds. These changes resulted in increases in the surge and wave heights over those in the original SPH. These changes were not reflected in later design guidelines for the flood protection system. April 1980: Flooding overtops east side of the London Avenue canal south of Robert E Lee, where 200 feet of sheet piling had been removed at a point where the levee was eroding. January 1981: Stability analysis performed by consulting engineers Modjeski and Masters shows that proposed higher levees for the 17th Street canal would fail in high water. Factors of safety less than 1.3 and as low as 0.8 were found for substantial portions of the canal. Additional studies were recommended. September 1981: Corps of Engineers issues a design memorandum and revised environmental impact statement in which it is observed: “There is an unresolved issue with regards to the three main outfall canals in New Orleans which empty into Lake Pontchartrain along the reach known as the New Orleans Lakefront. Return levees flank these gravity drainage canals for a considerable distance inland from the lake, tying into lift pump stations at the head of the canals. Since the time of project authorization, it has been determined that the return levees are inadequate in terms of both grade and stability.” Work was underway to raise the lakefront levees to a height of 16 feet. August 1982: At this time, only about half of the improved NOFDS project had been completed. Costs were estimated to have grown to $757 million, not including any work along the drainage canals, and project completion had slipped to 2008. The General Accounting Office (1982) observed: “We believe that improved planning is needed by the Corps to resolve certain environmental, technical, and financial issues. Environmental concerns have remained unresolved for almost 5 years after a court injunction prohibited the Corps from constructing certain parts of the projects. The Corps is considering a change in its solution of providing protection from constructing barrier structures at the entrance to the lake and the raising of some levee heights (Barrier Plan) to constructing much higher levees with no barriers (High Level Plan).” The report observed: “Costly project work at the drainage canals has not been reported to the Congress, and technical and financial concerns which may impede project completion remain unresolved.” Further this report observed: “Subsequent