Oroville溢洪道紧急恢复
加利福尼亚州奥罗维尔。
最佳项目，水/环境与卓越安全
所有者|结构工程师|领导设计公司：State of California, Dept. of Water Resources (DWR)
Other Stakeholders:加州水坝安全部；联邦能源监管委员会
General Contractor:Kiewit Infrastructure West Co.
分包商：钻技术钻孔和支线；商业金属公司
1968年，当美国最高的770英尺高的奥罗维尔大坝（Oroville Dam）配备了3,055英尺长的主溢洪道，以及从未使用过的紧急溢洪道。这在2017年2月发生了变化，当时数周的大雨充满了容量的水库，导致加利福尼亚的水资源部（DWR）从主溢洪道上增加了水的释放。
但是，沉重的流侵蚀了大部分溢洪道混凝土，迫使官员在评估损坏时握住水。大雨继续，湖越过紧急溢洪道，这是一个在大坝上设计的低斑点，类似于溢出的浴缸的边缘。
With the torrent undercutting the front of the emergency spillway’s weir and threatening to send an uncontrolled wall of water downstream, emergency managers issued an evacuation order for nearly 200,000 people living in Oroville and other low-lying communities nearby.
加利福尼亚DWR和联邦能源监管委员会（FERC）开始了一个为期10天的竞标期，紧急项目将在下一个冬季之前将受损的溢洪道恢复为功能。该项目团队在八周内动员了500多个重型设备，150名建筑管理人员和500名工匠。
“奥罗维尔溢洪道紧急恢复项目是一个令人难以置信的例子，说明了基础设施行业及其机构在短时间内可以在很短的时间内完成的工作，如果我们都有相同的目标，并且要实现这一目标的紧迫性，”执行项目总监，执行项目总监Jeff Petersen说。Oroville溢洪道紧急恢复项目。
在主要的溢洪道上，船员拆除了现有的混凝土和挖掘的土壤和岩石，以达到固体地基。然后，他们进行了批处理，并放置了超过340,000立方米的辊式混凝土（RCC），以填充开挖和140,000立方英尺的结构和水平混凝土，以重建溢洪道。还安装了一个新的无底层系统。
紧急溢洪道的主要工作包括建造706,000厘米的RCC Splashpad，建造为1英尺的升降机，总计120万平方英尺，一个相当于25个NFL足球场的区域。飞机板由1,450英尺长的地下叶桩墙支撑，该壁墙内置在基岩中，深度为35英尺至65英尺。
In April, the DWR began releasing water from Oroville Reservoir for the first time since the two-year, $1.1-billion emergency spillway reconstruction was completed in late 2018. The heavy rains and deep snowpack during the winter of 2019, as well as forecasts for additional storms, prompted the releases to help manage lake levels. The flow over the rebuilt concrete spillway, gentle at first, roared to 25,000 cu ft per second on April 6.
The crisis took many local residents by surprise. Oroville’s former mayor, Linda Dahlmeier, recalls turning her cellphone off during a short flight home from San Diego that day. “By the time I landed in Sacramento, they had called the emergency evacuation,” she says. “My daughter lives in that low-lying area with no cellphone service at her house. She only had about 15 minutes to get out, and that was with four of my grandkids. My knees just completely buckled. It was like living in the ‘Twilight Zone.’”
彼得森说，该项目的最大成就并不是任何一个人或实体执行的任务，而是反映了符合溢洪道设计，建筑和公共安全里程碑的集体团队合作，这是两步项目的，都具有出色的安全性能。
“对我们来说,实现的成就佤邦s felt back in April when we were able to watch the first water spill down the main spillway,” Petersen says. “More than 1,000 people from Kiewit, our subcontractors, DWR, its designers, stakeholders and key regulatory agencies put their lives on hold for 18 months to rebuild this project—and I don’t think we’ve ever been so excited to see water flow down a spillway.”
自从Spillway重建完成以来，本月初，DWR于本月初开始从Oroville水库释放水。DWR发言人说，联邦和州监管机构和DWR专家“同意Oroville Main Spillway正在按照设计的设计进行。”现场重建继续，随着该细分市场的完成，预计将于今年秋天晚些时候完成。
