SGER: Hurricane Katrina and Lessons for Prevention of Catastrophic Levee Failures Applicable to Other Similarly Threatened Areas in the U.S.

奖项：CMS-0611632PI: Raymond SeedInstitution：加州大学伯克利分校标题：SGER：卡特里娜飓风和预防美国其他类似受威胁地区灾难性堤坝倒塌的经验教训研究小组在卡特里娜飓风过后的几个月里进行了一项由美国国家科学基金会资助的实地调查（CMS-0553197），成功地捕获并记录了与新奥尔良堤坝倒塌有关的重要易腐数据和观测结果。第一次专题评估的意见载于以下报告（也可从参议院国土安全和政府事务委员会获得）：Seed, r.b., Nicholson, p.g., Dalrymple, r.a., Battjes， J., Bea, r.g., Boutwell, Bray, j.d., Collins, b.d., Harder, l.f., Headland, j.r., Inamine， M., Kayen, r.e., Kuhr， R., Pestana, j.m., Silva-Tulla， F., Storesund， R., Tanaka， S., Wartman， J., Wolff, t.f., Wootem， L.和Zimmie， T.(2005) 2005年8月29日卡特里娜飓风中新奥尔良堤坝系统性能的初步报告。UCB/CITRIS 05/01，加州大学伯克利分校CITRIS中心，2005年11月16日。这个新项目将继续收集易腐烂的数据，但将集中分析这些重要的实地执行情况个案研究。美国目前正忙于对严重受损的新奥尔良防洪系统进行紧急重建，从卡特里娜飓风中吸取教训并将其应用于目前正在紧急修复的这些系统，这是一种不同寻常的紧迫性。然而，从长远来看，这些经验教训对全国乃至全世界的防洪堤系统也是极其宝贵的。在卡特里娜飓风期间，新奥尔良防洪系统的多次失灵导致了灾难性的洪水，迄今为止已经夺去了1063人的生命，摧毁了美国的一个主要城市和大都市区，造成的（直接和间接）损失估计在2000亿到4000亿美元之间。这是世界历史上造价最高的一次工程系统故障。从新奥尔良防洪堤系统的表现，以及从紧急修复和抽水使被淹没地区脱水的经验中，我们可以学到一些可能至关重要的教训。在新奥尔良发生的几十种防洪系统故障中，溢流冲刷侵蚀、结构防洪墙和板桩防洪墙系统的脱支以及由此导致的墙系统故障、土堤防的下渗引起的稳定性故障都是典型的。在材料、几何形状和其他设计细节上有微小变化的类似的附近防洪系统元素的成功表现，代表了一个显著的对比和一个独特的机会来学习关键的经验教训，并提高我们对所涉及的各种机制的理解。这项研究的结果将显著影响这些系统的未来分析、设计和建设，不仅在新奥尔良地区，而且在整个国家也是如此。最近关于风暴径流、飓风频率和地震风险预测的进展表明，堤坝系统比人们普遍认为的要脆弱得多。由于缺乏连贯的国家堤坝安全计划（如国家大坝安全计划），该领域的研究也滞后，堤坝系统目前代表着不可接受的国家风险水平，通常既缺乏记录，也缺乏理解。至关重要的是，我们要从新奥尔良防洪系统在卡特里娜飓风中灾难性的失败中吸取教训，以便将来能够应用这些教训，以减少我们国家在其他地区遭受类似灾难性灾害的风险。

Award: CMS-0611632PI: Raymond SeedInstitution: University of California, BerkeleyTitle: SGER: Hurricane Katrina and Lessons for the Prevention of Catastrophic Levee Failures Applicable to Other Similarly Threatened Areas in the U.S.The research team conducted an NSF-sponsored field investigation (CMS-0553197) in the months following Hurricane Katrina that successfully captured and documented vital perishable data and observations related to levee failures in New Orleans. The observations from the first SGER are contained in the following report (also available from the Senate Committee on Homeland Security and Governmental Affairs: Seed, R.B., Nicholson, P.G., Dalrymple, R.A., Battjes, J., Bea, R.G., Boutwell, G., Bray, J.D., Collins, B.D., Harder, L.F., Headland, J.R., Inamine, M., Kayen, R.E., Kuhr, R., Pestana, J.M., Silva-Tulla, F., Storesund, R., Tanaka, S., Wartman, J., Wolff, T.F., Wootem, L. and Zimmie, T. (2005) Preliminary Report on the Performance of the New Orleans Levee Systems in Hurricane Katrina on August 29, 2005, Report No. UCB/CITRIS 05/01, CITRIS Center, University of California, Berkeley, November 16, 2005. This new project will continue the collection of perishable data, but will concentrate on the analysis of these important field performance case studies. With the Nation now engaged in emergency reconstruction of the heavily damaged New Orleans flood protection system, there is an unusual urgency in learning and applying lessons from Katrina to these systems currently under urgent repair. These lessons will also, however, be extremely valuable over the long term for levee systems throughout the Nation, and throughout the world. The multiple failures of the New Orleans flood protection system during the Katrina event resulted in catastrophic flooding that has to date claimed 1,063 lives, devastated a major U.S. city and metropolitan area, and produced estimated (direct and indirect) damages ranging between $200 to $400 billion. This represents the single most costly engineered system failure in world history. There are lessons of potentially vital importance to be learned from the performance of the New Orleans levee systems, and from the experiences with emergency repair and pumping to dewater the inundated areas. Overtopping scour erosion, unbracing of structural floodwalls and sheetpile cut-off wall systems and resultant wall system failures, and underseepage-induced stability failures of earthen levee embankments are all represented among the several dozen flood protection system failures that occurred in New Orleans. Successful performance of similar, nearby flood protection system elements, with small variations in materials, geometry and other design details, represents a striking contrast and a unique opportunity to learn critical lessons and to improve our understanding of the various mechanisms involved. The findings of this study will significantly influence the future analysis, design and construction of these systems, not only in the New Orleans region but throughout the nation as well.Recent advances concerning prediction of storm runoff, hurricane frequency and seismic risks suggest that levee systems are more fragile than is generally understood. In the absence of a coherent national levee safety program (such as with the National Dam Safety Program), research in this area lags as well, and levee systems currently represent an unacceptable level of national risk that is generally both poorly documented and poorly understood. It is critical that we learn the lessons to be learned from the catastrophic failures of the New Orleans flood protection system in Hurricane Katrina so that they can be applied in the future to reduce our nations exposure to similarly catastrophic disasters in other regions.