In 2009, South Korea started a large multi-purpose water project on its four major rivers. The main purposes of the Four Major Rivers Restoration Project (FMRRP), which are directly related to water itself, were: (1) securing water resources to combat water scarcity; (2) reducing flood risks by riverbed dredging and reinforcing levees; and (3) restoring the river's environmental functions. Despite socio-environmental opposition, the project was completed in 2011. This article reviews the sedimentation issues raised during and after the FMRRP regarding technological developments and the lessons learned from the project. A total of five sedimentation issues raised directly from the project are reviewed in this article: (1) riverbed dredging and sediment redeposition; (2) tributary headcut; (3) riverbed scour downstream of the movable weir structures; (4) sedimentation management schemes; and (5) a near-prototype river experiment facility. Each issue is addressed by identifying and analyzing field data, developing new numerical models, and testing at a large-scale experiment facility. From this project, we have found that a comprehensive numerical technique is required to predict the sediment issues as mentioned above in a watershed-scale riverwork.

2009年，韩国在其四大河流上启动了一项大型多功能水利工程。四大江河整治工程（FMRRP）的主要目的与水本身直接相关，包括：（1）确保水资源，应对水资源短缺；（2）通过河床疏浚和加固堤坝来降低洪水风险；（三）恢复河流环境功能。尽管遭到社会环境的反对，该项目还是于 2011 年完成。本文回顾了 FMRRP 期间和之后提出的有关技术发展的沉积问题以及从该项目中吸取的经验教训。本文回顾了该项目直接提出的五个沉积问题：（一）河床疏浚和泥沙再沉积；(2) 支流首切；(3)活动堰结构下游河床冲刷；（四）沉积物管理方案；(5) 接近原型的河流实验设施。每个问题都通过识别和分析现场数据、开发新的数值模型以及在大型实验设施中进行测试来解决。从这个项目中，我们发现需要一种全面的数值技术来预测如上所述的流域规模河流中的沉积物问题。