Building the World's Longest Earthen Seawall in South Korea

February 6, 2018

In 2006 thirty-four Cat® machines were called on to help complete the 20-mile-long Saemangeum seawall—the longest earthen seawall in the world. The government-funded project was launched in the 1990s to convert tidal flats (areas of nearly flat, barren mud, periodically covered by tidal waters) along the west coast of South Korea into new farmland and a freshwater reservoir to benefit both the local economy and residents.

The fleet used to finish the job included Cat off-highway trucks, hydraulic excavators, tractors, and soil compactors. Subcontractors owned many of the machines, and many of them worked closely with Cat Financial. Nineteen units were short-term rentals provided by the Cat Rental Store owned by the local Cat dealer.  

The machines were originally located in a quarry site, where they excavated medium and large stones used for the seawall. Next, the giant machines had to be moved from the quarry, one at a time, and put to work for 45 days and nights until the project was finally completed. 

Sin Seung Construction was responsible for completing the last kilometers of the wall. The company’s owner said, "We are a firm believer in Cat equipment and knew we could rely on them to help us meet our deadline.” He also cited exceptional performance and product support as key reasons his company chose to work with Caterpillar.

After completion, the seawall connected the towns of Gunsan and Buan with a surrounding population of about 77,000 people. The wall encompassed nearly 99,000 acres of new land—at that time roughly 60 percent of the size of Seoul City. It also created a 29,000-acre reservoir capable of supplying up to one billion tons of fresh water yearly to area residents. In 2007 a roadway was built on top of the seawall. And all this progress was made possible with Cat products. As our customer said, "We are ready and willing to meet the challenge."