From small rivers a new era rises up

I became a target of a formal complaint for participating in President Moon Jae-in’s 1 When I heard that the prosecutors dismissed our case for lack of evidence, I searched my case number on the Criminal Justice Portal. When I saw the result come up I let out a chortle. Due to this complaint, the rigorous deliberations by subject matter experts and environmental activists were reduced to a matter of ‘obstruction of commercial business’ under the official records. But also I found myself feeling a sense of relief and freedom. Until the dismissal, I had carried an irrational yet real possibility that at any given moment I could be ‘searched and seized’ by the prosecutors whilst under such an accusation for almost three years.

This complaint is only one small incident against a broader set of conflicts surrounding the Four Major Rivers Project. Over fifteen years ago, the Four Major Rivers Project was Lee Myung-bak’s administration’s (2008-13) flagship nation building project, even mobilising the National Intelligence Service to crack down criticisms expressed by civil society groups and media. Why was Lee so determined to develop rivers to that extent? To restore our rivers, we have to dig deeper into the drivers behind Lee’s agenda.

Rivers as the promise of development

In the late 1960s, the Han River polluted rapidly as Seoul’s population surged faster than the speed at which the sewage treatment infrastructure could be built. Until a massive construction program called The Han River Comprehensive Development Project began ahead of the 1988 Seoul Olympics in order to present foreign visitors with a “clean” river. The project dammed parts of the river to float cruise boats, build bridges, parks, apartments, roads and the sewage treatment plants as part of an all-in redevelopment scheme. This project was proposed by Lee Myung-bak, the then CEO of Hyundai Construction. Having joined the company as a rank-and-file employee prior to his rise as CEO, Lee poured his energies into developing the Han river.

Later he pushed through another initiative as the Mayor of Seoul (2002-06): The Cheonggyecheon Restoration Project (cheon meaning stream). Despite controversies over the adverse impacts on nature, history, and traffic flows, the project was completed speedily, and the public mindset shifted in favour of the newly “tidied” water feature in the heart of the city. Across the rest of the country, the sentiment of “if only our neighbourhood had a Cheonggyecheon too” quickly spread and lookalike projects of Cheonggyecheon+20 were created in local waterways. The popularity of The Cheonggyecheon Restoration Project propelled Lee politically all the way to the presidency.

Lee Myung-bak’s rise is a contradictory symbol of both miracle and the irreversible damage that rapid civil construction projects leave behind as a national legacy. For South Korea, once a war torn and poverty stricken nation with sewage flowing into the Han River, the process of grooming its rivers with riverfront parks, cruise boats rides, and scenic landscapes was synonymous with the progress of becoming a wealthy nation.

The Four Major Rivers Project as the pinnacle of the construction industry

From the 1960s to the 2000s, South Korea rapidly expanded its infrastructure programs from roads, bridges, ports, railways, to dams, water and sewerage systems. The civil construction projects demonstrated short-term economic stimulus almost instantly: project investments stimulated cash flows into the market and vitalised the local economies. But such a trend could not be sustained and the projects’ growth began to slow from the late 1990s, declining into the late 2000s.

The Dong River Dam Project serves as a key example of an over reach by the civic construction sector. Previously, other dams were largely justified as necessary infrastructure but the Dong River raised serious concerns about the lack of clear objectives and potential environmental damage such as water pollution and habitation degradation since the late 1990s. But the project was driven forward regardless, because it had become difficult to find genuinely suitable sites for new construction work. In 2000, the Dong River Dam was finally scrapped in the face of public opposition. In 2006, The Long-Term Comprehensive Water Resources Plan removed new dam construction plans and the pilot projects began to dismantle aging small dams as the move away from unnecessary infrastructure build was tentatively explored. However, the construction industry in South Korea remained powerful and against the government’s Plan, the industry drew up a business case for sixteen new dams in order to build again; and President Lee Myung-bak took this up as his political agenda.

The Four Major Rivers Project tore up the rivers nationwide with a full-spectrum construction blitz. President Lee promised to build Han-River-style waterfront parks across the country. He also spoke of “floating or waterside cities” with boats on the four major rivers. In its approach this project was an extension to a national scale of The Han River Comprehensive Development Project back in the late 1980s, in the earlier years of Lee’s career. Drawing from experience, he drove through The Four Major Rivers Project at lightning speed. Despite being promoted as flood prevention and water-quality improvement, post construction the weirs built leading up to the major rivers raised flood levels, and water quality deteriorated to its worst. In a country that until that point could drink river water, algal blooms emerged at such high toxicity levels that made purification for human consumption impossible. The public was furious against The Four Major Rivers Project.

When the construction era declines

The ill-advised Four Major Rivers Project was pushed through at lightning speed because a large share of the core power circles at the time — in politics, government, academia, media, and industry — supported it. This generation’s thinking was shaped by the lived experiences of the 1980s through to the 2000s, when civil engineering projects were synonymous with national development.

But now, fifteen years after completion, Korea’s civil engineering sector is heading downhill. The political forces that drove The Four Major Rivers Project are now in their seventies and eighties, and the momentum to lead new mega-scale construction drives has diminished. President Yoon Suk-yeol, claiming to be the unauthorised inheritor of Lee Myung-bak’s legacy, pushed for building fourteen new projects under the label of “climate-response dams,” but the planning phase demonstrated difficulty in finding any project large enough to prop up the old construction sector. It was also rumoured that the Yoon government failed to appoint any engineering experts who had worked on a project within the last decade, since the end of The Four Major Rivers Project. Instead, the appointments were filled with retired professors instead of experts and practitioners. With the decline of the Project, the industry and its generation were also fading into history.

When Dams grow old

With the decline of the construction era, the river dams themselves cannot avoid deterioration. The golden age of large-dam construction was from the 1960s to the early 1990s. During this time, the irrigation weirs that were built to supply agricultural water did not always have clearly recorded construction dates and as urbanisation advanced, many began losing their function and purpose. According to The 2021 National Water Management Master Plan, there are 33,942 irrigation weirs nationwide; of which 5,857 are damaged and 3,826 in decommissioned or abandoned condition.

With the passage of time, urbanisation continues to intensify and an increase in the regional weirs and agricultural dams becoming dysfunctional from lack of use are on the rise. Within this context, there was a pilot project to remove irrigation weirs hidden throughout the tributaries, but it failed to spread. Even experts and civil society groups who had long thought about weirs had to put aside these matters against the giant whirlpool of incidents surrounding the Four Major Rivers Project. Particularly, as the algal-bloom damage in major rivers became particularly severe, the entire environmental movement had no choice but to cling urgently to restoring the Four Major Rivers.

There were political factors, too. In South Korea’s effectively two-party system, President Lee Myung-bak of the conservative Saenuri Party pushed the Four Major Rivers Project, while the progressive Democratic Party opposed it. As the disagreement remained along partisan lines, an alternative vision remained absent. It became increasingly clear that a new generation would have to approach this issue from the ground up before a new vision could bloom.

Village Streams as the promise of restoration 

In 2016, I reread for the first time in ten years, a pilot-project report on removing irrigation weirs that the Ministry of Environment had published in 2006. According to the Ministry's Korea Institute of Civil Engineering and Building Technology, water quality improved most clearly after the removal of the Gokneung 2 Weir: biochemical oxygen demand (BOD) recovered from around Grade 3–4 to Grade 1.

I emailed activists across the country. I wanted to find colleagues who would start by making small, concrete wins to correct the wrongs of the Four Major Rivers Project. A reply came from the City of Seongnam in Gyeonggi Province. They wanted to try removing an irrigation weir on a tancheon (meaning an urban stream running through the city) which was no longer used. Over the next five years, we persuaded the city government, the Ministry of Environment, and the local council, and removed three irrigation weirs. Volunteer scientists and experts collaborated to collect and analyse the data. Flood risks were also carefully assessed. The results were dramatic - flood levels fell by 1 metre; the endangered Kentish plover birds returned to its habitat; and for the first time, water quality recorded Grade 1.

What most mattered was that, at each stage of the removal we closely analysed local conditions and actively engaged with the local stakeholders. Nothing about producing these small successes was easy. And we need more challenges, more successes, and more failures. One by one, we must remove and document the many barriers that still cut across rivers even after they have lost their purpose. We must share the results created through collaboration among diverse stakeholders, and in the process build the social capacity called trust—only then can we move to the next stage. 

To restore rivers, we must confront more deeply this process of understanding rivers as part of the life of a community, and make changes from within. Because this resolve that starts with small rivers may be the beginning of a vast transformation.

Editor’s Note: Dams as a double-edged sword for rivers across the world *

For thousands of years, humanity has built weirs and dams across rivers to store water, prevent floods, and generate energy. But in doing so, we have also left profound impacts on river ecosystems—disrupting flow regimes and water temperatures, and blocking fish migration. In 2010, 43% of the world’s rivers were fragmented at a moderate level or above, and that figure is projected to reach 89% by 2030. This study examined roughly 6,400 existing dams and 3,400 planned dams worldwide; in reality, however, there are millions of large and small structures, so the true extent of fragmentation may be underestimated.

Brazil’s Belo Monte Dam in the Amazon is one among many emblematic cases showing the harms dams can cause. About KRW 5 trillion was spent on its construction. The dam reduced flows in the Volta Grande stretch of the Xingu River by 80%, affecting 130 km of waterways. As a result, 66,000 hectares—nearly 1.1 times the area of Seoul—were flooded, harming five municipalities, tens of thousands of residents, and at least two Indigenous territories. The courts halted operations seven times because required social and environmental mitigation measures were not implemented. Environmental authorities issued 36 fines after 2012; yet of 47 interim remedial measures recommended in the process, 34 were not complied with.

As of 2024, roughly 56% of Brazil’s electricity comes from hydropower, while solar and wind account for 24%. Hydropower has the advantage of being a low-carbon power source, but the losses borne by Amazon communities and ecosystems are still being underestimated.

* Ro Gun Woo is the Programme Manager Ecology at Regional Office East Asia of the Heinrich Boell Foundation.