preparedness, and forecasting for New Orleans is such that many parts of the IPET studies never could be “final.” Hurricane protection is an ongoing, work in progress to which the IPET has made noteworthy contributions that serve as a platform for future inquiry and for the development of research priorities.
The remainder of this chapter presents the committee’s observations and comments about the IPET draft final report and is organized according to the five IPET study objectives.
The IPET evaluations and reports in this area advanced greatly the understanding of the pre-Katrina state of system and its vulnerabilities. Volume I explains, for instance, that the hurricane protection system “…did not perform as a system” (IPET, 2008). In discussing the administrative and organizational history of the HPS, the IPET draft final report makes it clear that the “system” was constructed in a piecemeal fashion, “in many separate steps over a long period of time” and represented a history of “continuous incompleteness” (Ibid., p. 31). Details on this region’s geologic setting also explain widespread subsidence and how this affected levee heights, stability, and reliability. The IPET report also explains how the system was incomplete in some areas, that there were different vulnerabilities across the region, and that parts of the system were unreliable and had been inadequately designed. These types of evaluations were overdue for this region; unfortunately, it took a disaster on the scale of Hurricane Katrina to provide the impetus for this kind of study. This explanation of the pre-existing condition of the HPS marks one of the important contributions of the IPET studies and will be essential information for future hurricane planning and construction activities in the region.
The IPET work in this area represents an important advance of scientific understanding of Gulf of Mexico hurricane storm surge and waves. The IPET did a good job of explaining the storm surge generated by Hurricane Katrina, how waters from the surge entered into the New Orleans metro region from the east and from the north (across Lake Borgne, into Lake Pontchartrain, and ultimately into the city’s outfall canals and the Inner Harbor Navigation Canal), the role of the Mississippi River Gulf Outlet in exacerbating storm surge (minor, if any), and inundation depths across the city. The IPET work also importantly identified the significance that the areal extent of Katrina played in determining