Seoul, South Korea
City population: 9776000
Duration: 2003 – 2005
Implementation status: Completed
Scale: Micro-scale: District/neighbourhood level
Project area: 252000 m2
Type of area: Central Business District / City Centre, Other
Last updated: October 2021

The Cheonggyecheon Stream Restoration Project saw the dismantling and removal of an elevated freeway and the uncovering of a 5.84km section of the Cheonggyecheon historic stream in the centre of Seoul, South Korea (Ref. 2). One of the world’s largest and most densely populated cities, the revitalisation of the Cheonggyecheon Stream has provided Seoul with an ecologically sensitive green pedestrian corridor in an area that was previously recognised as being congested, overpopulated and polluted (Ref. 4). The restoration has provided environmental, social and economic benefits within its immediate proximity (Ref. 2). In addition to becoming a "vehicle for revitalisation, urban renewal and economic development", it has "also signified a shift in Korean planning priorities", with both city authorities and residents now placing an emphasis "on health, sustainability and social responsibility" (Ref. 4). It has further "become a template for planning intention and action across South Korea" (Ref. 4).

Cheonggyecheon Freeway before the NBS intervention
https://www.landscapeperformance.org/case-study-briefs/cheonggyecheon-stream-restoration#/sustainable-features

Overview

Nature-based solution

  • Grey infrastructure featuring greens
  • Riverbank greens
  • Parks and urban forests
  • Green corridors and green belts
  • Blue infrastructure
  • Rivers/streams/canals/estuaries
  • Wetlands/bogs/fens/marshes

Key challenges

  • Climate action for adaptation, resilience and mitigation (SDG 13)
  • Climate change adaptation
  • Water management (SDG 6)
  • Flood protection
  • Stormwater and rainfall management and storage
  • Improvements to water quality
  • Green space, habitats and biodiversity (SDG 15)
  • Habitat and biodiversity restoration
  • Green space creation and/or management
  • Environmental quality
  • Air quality improvement
  • Regeneration, land-use and urban development
  • Promotion of naturalistic urban landscape design
  • Economic development and employment (SDG 8)
  • Tourism support
  • Cultural heritage and cultural diversity
  • Protection of historic and cultural landscape/infrastructure

Focus

Creation of new green areas, Management of rivers and other blue areas, Ecological restoration of degraded ecosystems

Project objectives

The restoration project had five main purposes: to signal a transfer to sustainable urban development paradigm; to promote the recovery of eco-friendliness; to remove risks related to the concrete covering and elevated highway; to aid the restoration of historical and cultural spaces, and to provide balanced development between different areas within the city (Ref. 1). To achieve these purposes, three objectives were specifically targeted: restoration of a natural environment and enhancement of the quality of life; restoration of history and culture; and revitalisation of the economy (Ref. 1). As summarised by Ref. 5, "The essence of the restoration program was “space creation” – a place where the city’s residents could enjoy the ‘liveliness of a friendly Seoul.’ Defined concepts of history (tradition), culture (modernity), and nature (future) were introduced to confer diversity onto the respective sections of restored areas". Flood management was a further key component of the restoration, with particular emphasis on its being able to respond to "increasing incidences of flooding and the frequent torrential showers during summer [hence] the city built embankments that can withstand a 200-year-level extreme flood" (Ref. 5). Additionally, the number of bridges along the route of the restored stream were to be minimised "in order to transmit a maximum amount of water" (Refs. 5 & 6).

Implementation activities

By removing the overhead freeway and opening up the stream, the stream has been re-naturalised. Benefits were hoped to be had on the ecosystem through improving both water and air quality and increasing biodiversity; on society, particularly through providing flood protection and reducing the impacts of the urban heat island effect; and on the economy, particularly through boosting tourism and foreign investment, and by improving the profitability of existing businesses adjacent to the stream (Ref. 2).

Climate-focused activities

Climate change adaptation:

  • Increase or improve urban vegetation cover to help reduce outdoor temperature
  • Create or improve outdoor spaces to help people escape from urban heat
  • Renaturalization of rivers and other water bodies

Biodiversity conservation or restoration-focused activities

Biodiversity restoration:

  • Rehabilitate and restore damaged or destroyed ecosystems

Main beneficiaries

  • Local government/Municipality
  • Private sector/Corporate/Company
  • Citizens or community groups
  • Young people and children
  • Other

Governance

Management set-up

  • Government-led

Type of initiating organisation

  • Local government/municipality

Participatory approaches/ community involvement

  • Taskforce groups
  • Co-management/Joint management
  • Other

Details on the roles of the organisations involved in the project

The government led the restoration of the stream, headed by the Mayoral candidate of the time, Myungbak Lee, who "established as his major campaign pledge the restoration of Cheonggyecheon" (Ref. 8).

Project implemented in response to ...

... an EU policy or strategy? No
... a national policy or strategy? No
... a local policy or strategy? No

Financing

Total cost

€100,000 - €500,000

Source(s) of funding

  • Public local authority budget

Type of funding

  • Earmarked public budget
  • Other

Non-financial contribution

No

Impacts and Monitoring

Environmental impacts

  • Climate, energy and emissions
  • Lowered local temperature
  • Reduced emissions
  • Environmental quality
  • Improved air quality
  • Water management and blue areas
  • Improved water quality
  • Increased protection against flooding
  • Improved stormwater management
  • Enhanced protection and restoration of freshwater ecosystems
  • Green space and habitat
  • Promotion of naturalistic styles of landscape design for urban development
  • Increased number of protection areas
  • Increased green space area
  • Increased conservation or restoration of ecosystems
  • Increased number of species present
  • Increased ecological connectivity across regeneration sites and scales

Economic impacts

  • Increase of jobs
  • More sustainable tourism
  • Increased property prices
  • Stimulate development in deprived areas
  • Reduce financial cost for urban management
  • Attraction of business and investment

Socio-cultural impacts

  • Social justice and cohesion
  • Improved access to urban green space
  • Health and wellbeing
  • Improved physical health
  • Gain in activities for recreation and exercise
  • Cultural heritage and sense of place
  • Improvement in people’s connection to nature
  • Protection of historic and cultural landscape / infrastructure
  • Education
  • Increased support for education and scientific research
  • Increased knowledge of locals about local nature

Type of reported impacts

Achieved impacts

Presence of formal monitoring system

Yes

Presence of indicators used in reporting

Yes

Presence of monitoring/ evaluation reports

Yes

Availability of a web-based monitoring tool

No evidence in public records

References

Cheonggyecheon Stream after the NBS intervention
https://www.landscapeperformance.org/case-study-briefs/cheonggyecheon-stream-restoration#/sustainable-features
Cheonggyecheon before the restoration (2001, left) and after the restoration (2005, right)
https://www.coolgeography.co.uk/advanced/River_Restoration_Conservation.php
Cheonggyecheon Stream as an NBS
https://urban-regeneration.worldbank.org/Seoul
Information about this nature-based solution was collected as part of the UNA global extension project funded by the British Academy.