On Thursday 13 October in the afternoon, after the excursion at KICT, it was time to head towards the Cheonggyecheon Stream for a recreational tour, followed by a visit to the Cheonggyecheon Stream Museum. For the tour, the group was divided into three subgroups. Each subgroup was assigned a tour guide for a tour of two hours. This report is based on the information provided by the tour guide from group C, a retired seventy-year-old Korean man who had executed the study literature, and information gathered at the museum.

The Cheonggyecheon Stream flows through Seoul’s old city center that used to play an important role in the everyday life of the inhabitants. At that time, water flowed from the tributaries in the mountains into the Cheonggyecheon Stream and the inhabitants believed that the water had a healing effect. However, in the early 1900s the stream was perceived as a barrier for urban development and the water quality of the stream rapidly degraded because of industrialization, population increase, and changes in lifestyle. This resulted in the nickname ‘city’s cancer’. After the plan emerged in 1936 to eliminate the stream, the first actions to cover the tributaries of the stream and the stream itself started in 1958. In 1977, the complete stream was covered, and an elevated six-lane highway was present over the stream within the city center.

After the mid-1990s, the growth and development-oriented paradigm that has been actively present during the generations started to shift after collapse accidents of a bridge and store within a short period, alongside with the Asian Financial Crisis in 1997. Sustainable development started to become more important than immediate quantitative growth, because the Koreans realized that the rapid development led to the destruction of a lot of historical and cultural heritages, one of them being the Cheonggyecheon Stream.

The restoration of the Cheonggyecheon Stream was completed in 2005, resulting in a 11-kilometer-long stream with a lot of green on both sides. The stream flows into the Jungnangcheon river. The Cheonggyecheon Stream flows rather straight and is smaller than it used to be due to the urban development in the area and it is desired to create a more natural pattern with lower flow velocities. The water from the Cheonggyecheon Stream is being pumped up and is also used to discharge rainwater during periods with a lot of precipitation, resulting in a water level rise of sometimes two meters, which usually occurs maximum two times a year. The two Figures below respectively show the start of the Cheonggyecheon Stream and the gates that will open for large quantities of rainwater. At the start of the restored steam, one of the original bridges has been reconstructed using original and new stones.

As a result of the restoration, the elevated highway was removed. This resulted in fewer cars on the roads and an increase of public transport use. This phenomenon can be explained by the Braess paradox, which says that by taking away space in an urban area the traffic flow can be increased. The transition of private vehicle usage towards public transport due to the Cheonggyecheon Stream Restoration Project is briefly described in the micro study regarding smart and sustainable transport.