Thursday, July 1, 2010
Dams and Dredging: Korea's River “Restoration” Project
Seoul is a city of 10 million people now, but hundreds of years ago, it was a newly founded village along the banks of a pretty creek called Chonggyecheon. As the city grew, the creek became a sewer and finally was covered over by concrete and a freeway. Until recently, that is, because Mayor Lee Myung-bak brought the creek back to the daylight and pushed construction of a semi-natural running water experience for the urban dwellers in Seoul. We were impressed with the creek walk as an urban park, though water from the Han River is pumped at considerable energy costs to enhance the flow.
Now Lee is the nation's president and he seems determined to re-design the nation's four largest rivers, an objective that seems much less wise. The Han is one of South Korea's four major rivers, along with the Nakdong, Geum, and Yeongsan . From a watershed that gathers runoff from mountains to the east, the great Han River passes through the capital city of Seoul (37°35'N), then turns northwest to enter the ocean at the northern boundary of the country at the Demilitarized Zone (37°46'N). Late last year, excavators began carving away riverside bluffs to as much as double the width of the channel, while also digging out miles of riverbed to deepen it by 12 to18 feet. On the two days we explored a 6-mile stretch along the south fork of the Han River near Yeoju, construction crews were at work on 3 dams (weirs) while trucks were constantly being loaded with riverbed sand and gravel to be added to mountains of material already piled nearby. We had never seen so many gigantic excavators at work at once.
Yet this is just one part of a much grander $20 billion project. A total of 16 new dams are planned on the main channels of the four rivers, plus 5 more on their tributaries, while enlarging 87 existing small dams and armoring over 200 miles of riverbanks. The big dams under construction were close enough together so that the series of excavated “water basins” and gates could conceivably become a continuous canal. Opponents of the project think that is exactly the point, as a navigable canal connecting the nation's rivers was a key objective for President Lee when he took office, until national opposition stopped that grandiose plan. The current effort is part of Lee's “Green New Deal,” with stated objectives to store water against the prospects of drought, prevent flooding, improve water quality, restore river ecosystems, promote river-related recreation, and stimulate the economy (read more about the government program here)
The goals sound commendable, but a closer look raises questions. Clearly, lots of money is moving toward jobs and construction company profits. But, as we learned from the environmental group KFEM (Korean Federation for Environmental Movement) (KFEM blog here) at their headquarters in Seoul, and then with others from the KFEM Yeoju office, who took us along the Namhan--the south fork of the Han River--the listed benefits seem exaggerated. This nation, though densely populated, has a good water supply; episodes of flooding occur primarily on upper tributaries, rather than the main channels where the work is focused; and the engineering approach seems likely to degrade water quality, because slowing the flow will increase accumulation of algae and pollutants. Most blatantly, the removal of natural wetlands and streamside vegetation is not “river restoration,” but rather destruction of habitat and natural processes.
The United States went through a river damming and channel straightening/concrete armoring stage in the last century. In California we lost 90% of our wetlands and riparian woodlands and our extensive list of endangered species is closely tied to that lost habitat. We, along with many other nations, learned that a more effective way to manage watershed systems is to protect and restore wetlands and allow floodplains to absorb high water episodes, regulating those flows while reabsorption and riverbank vegetation filters impurities.
So it was sad to watch the living river-bed being pulled out and lush riverside plateaus being excavated, to know that endangered plants and animals were being pushed even closer to extinction, and that small family farmers near the river were also being displaced. Though the construction destruction continues every day now, opponents of the project are determined that it must stop. On a poster in the Yeoju KFEM office, an excavator is being restrained by an aster plant, one of the endangered species being threatened by the project. Mr. Ma told us the words say, "Be Persistent, It is Your River."