Cheonggyecheon Stream

As the renovation involved the demolition of the Cheonggye Highway and the restoration of the Cheonggyecheon Stream, the entire redevelopment area has been converted into open spaces and public green areas, hosting recreational events and cultural activities.

On the economic side, the renovation project significantly increased the attractiveness of the area, which consequently led to a new influx of businesses and economic activities. The area saw a 3.5% increase inthe number of economic activities compared to the beginning of the project, as well as an increased number of employees by almost 50,000 from the end of the project until 2012. These changes in employmentand businesses’ structure are also given by the shift of the downtown area into the city financial and professional district from the previous vocation for manufacturing. The increased attractiveness of the areaalso resulted in a 30% land appreciation brought by the project, which significantly increased the real estate value of the downtown neighborhoods. Thanks to the renovated pedestrian connections built toconnect different city attractions, the stream became an important spot for tourists and transient population.

The major impact brought by the stream renovation is connected to the environmental benefits generated by the creation of new public green areas. The new 163,000 sqm of green public spaces and therestoration of the water body ecosystem significantly reduced the temperatures of the area and mitigated the heat-island effect. In addition, these measures helped to reduce the flooding risks as the nature-based solutions implemented helped to strengthen the city urban resilience and climate adaptation. The green areas and the change in mobility systems in the area significantly reduced air pollution, decreasing PM-10 levels, nitrogen dioxide and volatile organic compounds. Moreover, the provision of vast green areas improved the biodiversity of the district by 639% and helped to preserve and strengthen the urban ecosystem. In general, the project followed a circular process for the demolition of the existing highway, by recycling or reusing the scrap iron, steel, waste concrete and asphalt extracted from the demolition.Lastly, the project also built a new sewage treatment and a new water management system, where the highly polluted rainfall is separated into a segregated pipeline and treated in the treatment facilities, thus without flowing directly into the stream.

The most important social benefit brought by the regeneration of the Cheonggyecheon Stream is the significant shift to a more sustainable mobility in the entire downtown area. In fact, the replacement of the highway with open public spaces led to the creation of a mass transit-oriented system, with an increase in public transport capacity and the construction of a pedestrian roads network. The intervention drove a crucial shift to a public transportation system, decreasing the traffic volume in the downtown area by 7% in 2007 and increasing bus ridership by a sharp 15% after the completion of the renovation project. The benefits brought by the new public spaces and the improved transportation systems pushed car users to switch to public transportation. The redevelopment also focused on ensuring public safety for the downtown residents. Firstly, the highway needed to be demolished as it presented important structural flaws and severe corrosion levels of its steel components, threatening the citizens’ safety. In addition, the stream restoration helped to decrease the flooding risk in the area, which was extremely high before the renovation. Another important positive effect brought by the stream regeneration has been the reinforcement of the historical identity of the downtown community, achieved by renovating the historical streets and buildings and restoring the original stream flow with its historical bridges. In addition, the stream public areas became a renowned venue for cultural events and recreation activities, helping to preserve the cultural heritage of the area and the city. Lastly, the successful regeneration and the consequent benefits brought by the project significantly improve the awareness of citizens on environmental issues, as a survey conducted after the completion of the intervention showed an increased willingness-to-pay for renovation projects and environment-focused restorations.

The Cheonggyecheon Stream renovation projects did not receive any environmental or sustainability certification or protocol.

The project had been entirely financed through public funding provided by the Seoul Metropolitan Government with the municipal capital budget.

Being developed as a public project, the Stream renovation had been entirely financed with the resources provided by the Seoul Metropolitan Government. The Government provided the entire project budget of USD 345 million which has been secured from three different budget sources. The first USD 89,7 million, around 26% of the total budget, were taken from the resources allocated for the demolition and reconstruction of the Cheonggye highway, already present in the city masterplan. Another 26% was secured by the downsizing of less urgent municipal projects and by improving the efficiency of the city administration work procedures, which saved around USD 89,7 million from the municipality budget. Lastly, the remaining USD 165,6 million was secured from general accounting adjustments to the municipal budget of the city. These accounting adjustments and savings on existent municipal resources only amounted to about one percent of the entire yearly municipal budget and helped the government to avoid recurring to debt instruments and increasing the financial burden on its budget. The redevelopment was also conducted establishing several tax-based incentives. During the renovation project, the Municipality offered economic support to businesses and established special agreements with vendors who had to move due to the project construction.

Amirtahmasebi, R., Orloff, M., Wahba, S., & Altman, A. (2016). Regenerating Urban Land: A Practitioner’s Guide to Leveraging Private Investment, World Bank Group, Washington DC. Availabe here.

Image from TwilightShow, retrieved here. Used under Standard License.