Project Location: Seoul, South Korea
Timeline: 2002 -2005 (3 years and 6 months)
Architects: Mikyoung Kim Design
Client: City of Seoul
Seoul, the capital of South Korea, is confronted with many significant issues. The effects of overpopulation and urbanization have resulted in a multitude of challenges, including scarcities in housing, transportation, and parking facilities, as well as the worsening of pollution levels and the unsustainable exploitation of resources. It is always gridlocked. Over a decade, urban and industrial development suffocated the remaining traces of nature in the city’s heart, notably in the congested and flat CBD.
Hoping to spur economic growth by providing new recreation options to residents and solve the city’s chronic runoff problems, The Seoul Metropolitan Government decided to do something bold. An initiative to transform the urban environment of the massive arterial highway by removing it and replacing it with a long, meandering park and stormwater mitigation system.
Degradation of the River
The Cheonggyecheon River is situated amid a historically significant neighbourhood. The first deterioration of the site can be traced back to the 15th century when many factors contributed to its decline. These factors include the expansion and depth of the river channel, the building of a stone and wood embankment, the use of the watercourse as a means of waste disposal, and the heightened sedimentation caused by the deforestation of the surrounding regions. Despite undergoing continuous dredging and modifications throughout the twentieth century, the river channel in the 1950s remained mostly a seasonal stream used by individuals for laundry purposes and as a recreational space for children.
As Seoul underwent a gradual transformation from a mostly rural area to a sprawling East Asian city, the Cheonggyecheon, referred to as the “clear valley stream,” deteriorated into a polluted waterway. The primary function of the stream in question was to serve as Seoul’s central sewage and drainage system, primarily designed to mitigate the risk of flooding.
By the year 1970, the area next to the river was characterized by the presence of slums. Additionally, the quality of the water in the river deteriorated with time due to a series of human interventions, including the process of channelization followed by the application of a concrete layer.
With the rapid progression of urbanization and industry, along with the widespread adoption of automobiles, the riverbed transformed, being repurposed into a 6-kilometre roadway. Above this roadway, a 5.8-kilometre elevated highway was constructed, boasting six lanes to accommodate the increasing vehicular traffic. Before the process of restoration began, the daily volume of vehicles that passed through this particular section amounted to almost 168,000. Among them, a significant proportion of 62.5% constituted vehicles engaged in traffic.
The ramifications of the very crowded transportation system along Cheonggye Street have become more severe. The levels of air pollution, namely criterion pollutants, were found to be much higher than the permitted thresholds. Additionally, the pollution caused by nitrogen oxide is above the established environmental air quality guideline for the city of Seoul. In addition, the concentrations of benzene, a volatile organic compound (VOC) known for its carcinogenic properties, were found to be elevated.
According to a health awareness study conducted among those living or employed near Cheonggyecheon, it was observed that the prevalence of respiratory disorders was more than twice as high compared to individuals residing in other geographical regions (SDI, 2003A). In conjunction with atmospheric pollution, the noise pollution observed in this particular region exceeded the prescribed benchmarks for commercial zones, hence posing a significant impediment to the creation of a desirable residential and occupational milieu.
In the year 2000, an engineering study was conducted which revealed the presence of structural deficiencies in the aforementioned roadways, hence highlighting the imperative need for a significant rehabilitation endeavour. The degradation and contamination of the Cheonggyecheon River stream may be attributed to the processes of urbanization, transportation, and industrial activities.
The objectives established for the urban revitalization initiative included the restoration of Cheonggyecheon’s natural ecosystem and the development of a public space that prioritizes human needs and experiences.
The proposed project included a range of objectives, including the restoration and landscaping of the stream, the establishment of measures to ensure water resource sustainability, the implementation of sewage treatment systems, the management of traffic flow, the construction of bridges across the river, the preservation and restoration of historical assets, and the effective resolution of social problems.
In addition to the aforementioned, the plan was formulated with the objectives of the restoration of cultural assets, as well as the conservation of all dug heritage pieces throughout the building process. Enhance the overall quality of air, water, and living conditions. The objective was also to establish a connection between the two geographically divided areas due to the river.
In the year 2003, the river underwent a process of re-exposure and was subsequently designated as the central element of a broader initiative aimed at revitalizing the urban environment. The rerouting of traffic, construction of bridges across the river, establishment of public parks and recreational areas, and renovation of nearby places of historical and cultural significance were undertaken. The enhancement of environmental circumstances resulted in the establishment of a focal point that has value in historical context and possesses aesthetic allure.
The waste that was generated as a result of the destruction was subjected to recycling processes and then used again. The process of urban redevelopment included the transformation of the site into a human-centric and ecologically conscious area, with a shoreline and pathways that run alongside the stream. Embankments were constructed to mitigate the most severe floods that the city may experience during the next two centuries. A total of 13.5 meters were designated to accommodate walkways, two-lane unidirectional roadways, and loading/unloading zones situated on both sides of the stream. A whole sum of 22 bridges was constructed over the Cheonggyecheon, including 5 bridges designated for pedestrian use and 17 bridges designed for motor vehicle traffic.
The stream that has been restored can be accessed from a total of 17 different sites. Terraces and lower-level pavements were constructed along both the top and lower segments of the stream, while the middle part was specifically planned to serve as an environmentally sustainable area. The incorporation of river parks and public art in many sites was undertaken to establish a platform for hosting performances and cultural events, while simultaneously augmenting the total capacity for public engagement and pleasure within the newly developed area.
The process of enhancing the aesthetic appeal of historic streets and structures was undertaken, with particular attention given to the restoration of the Gwangtonggyo Bridge. Originally constructed in 1410 to span the Cheonggyecheon Stream, this bridge was meticulously restored to its former condition, incurring a substantial expenditure of more than $5.9 million.
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