Saemangeum Seawall was built in a tidal flat zone on the Yellow Sea (The world's second largest tidal flat). The seawall is 33 miles long. At an opening ceremony, incumbent president Lee, Myung-Bak has commented that Saemangeum would be “. . . the kernel and the gateway of South Korea’s west coast industrial belt,” and is “another effort by us for low-carbon and green growth, along with the four-river project.”  The barrier was then used to reclaim land by filling.The newly reclaimed land to be used for industrial activity (the region has little), golf courses and water treatment plants.
Free economic zone was established to promote business activity. It provoked a major conflict between the government and environmentalist concerned about many impacts, especially related to biodiversity and the problematic effect it has on a major migratory bird problem. It also had significant impact on aquaculture and fisheries and those affected were involved in the protests.
“Saemangeum case sued by local people and NGOs in 2001 had shown rise and fall during the legal proceedings appealed. The compromise suggestion proposed by the court lost the authority due to the refusal to accept it by the government. The Administrative Court ruled the partial winning for the plaintiff (local people and NGOs) on February 4, 2005, but the Higher Court dismissed the original decision and gave losing to the plaintiff on December 21, 2005. Finally, the Supreme Court concluded Saemangeum case to raise a hand of the defendant (the government) on March 16, 2006.”
President Lee was a former CEO of a Hyundai Engineering & Construction company; local people are not surprised about his support of the project. Mainly NGOs, experts and religious groups have carried out civil movement against this project since 1999.
Although civil movement outside of Saemangeum area was strong, the effort and practice of local people in Saemangeum area were relatively weak, however. Recognizing that it is difficult to refuse bravely the public work made most of local people think of the project as inevitable. Majority of local people already received the financial compensation from the government and believed that the Saemangeum project would develop their local economy.
The Seawall was begun in 1999 with various delays and it was not completed until 2010. The seawall is slightly longer than the Zuidesee Seawall in the Netherlands.