Cheonggye Expressway – Seoul, South Korea



Perhaps more so than any American example, the Cheonggyecheon Expressway in Seoul demonstrates that a major highway can be removed without major negative impacts, when accompanied by a com­prehensive strategy of Transportation Demand Management and transit expansion.

Un­like most major U.S. cities, Seoul enjoyed signifi­cant mass transit use prior to the project. How­ever, like U.S. cities, it was increasingly choking on its own traffic, with average annual increases in the 1990s of 13 to 15%.

The Cheonggyecheon project illustrates the tangible economic and environmental benefits that can flow from urban design that is driven in large part by quality-of-life perceptions.


Transportation Demand Mangement

Through a combination of incentives and disincentives, the city of Seoul, South Korea, has made mass transit a progressively more attractive alternative to the automobile for trips into and within central Seoul. Two key components – the “No Driving Day” program and bus system improvements – were implemented in the months after demolition of the Cheonggye Expressway. These were part of a much larger set of programs addressing congestion, not just in the Cheonggye corridor but throughout Seoul.

  • In 1996, the city of Seoul began charging private vehicles with less than three occupants a toll of 2000 won (about $2 US) at two major points of entry to the central business district, Namsan Tunnels #1 and #3, during weekdays and for a shorter period on Saturdays. Within a year, traffic fell by 14% and speeds increased 38%. While traffic on alternate routes increased 6%, speeds increased by 16%. Tunnel traffic has since returned to pre-toll levels, but the average number of passengers in vehicles has gone up, and average speeds have remained faster. 
  • In 2003, a voluntary “No Driving Day” program was introduced. Participants who leave their cars at home one weekday per week are now eligible for benefits including half-price tolls, 10-20% discounts at public parking lots, a 5% reduction in auto taxes, gas, maintenance and car wash discounts. By 2006, the program had resulted in a 4% decrease in traffic, a 10% reduction in carbon emissions, and annual fuel savings of $50 million (US). 
  • Starting in 1997, the city instituted regular fee increases for public parking, and in 2004 it announced that it would be reducing the supply of public parking downtown. The city has also sought to restrict the parking supply by lowering parking requirements for commercial development, and a residential parking permit program has been established.
  • Gas taxes have been increased, and an incentive-based Transportation Demand Management program for employers implemented.
  • Finally, in 2004, the city’s bus system was fundamentally restructured. Most significantly, a network of median bus-only lanes introduced in 1996 was greatly expanded. By 2005, four routes extended 22 miles; by 2007, the system had reached seven routes and 42 miles; by 2010 it encompassed 12 routes and 73 miles. In 2004, the existing network of curbside bus-only lanes was also expanded. Fares and schedules were coordinated, and integrated with the subway system, and services were color-coded (local downtown buses, for example, are branded yellow). A smart card was introduced, and ITS technology is now used to manage the system. The results: within months, rider satisfaction had reached 90%, speeds in bus rapid transit corridors had improved by 33% to 100%, and accidents and injuries on all routes had fallen by a third. Between January and late May of 2005, meanwhile, bus ridership increased by nearly a million passengers per day, or almost one-quarter.

The Cheonggye Expressway

Cheonggyecheon (“clear valley stream”) is a former seasonal waterway in the city center of Seoul, South Korea. Between 1958 and 1976, the stream was covered and replaced by the Cheon­ggye Road and Cheonggye Elevated Highway, or Cheonggye Expressway. Prior to demolition, combined traffic counts on both roads were ap­proximately 168,000 vehicles per day, about five-eighths of which was through-traffic.

Between 2003 and 2005, the roads were removed and the stream was restored. The stream is now the centerpiece of a 3.6-mile linear park with new two-lane, one-way streets on each side of the park.

While the city’s official budget was approximately $385 million (U.S.), media sources have estimated the project’s total cost at more than $900 million (U.S.).

Post-Project Evaluation

  • In the 15 months after its opening, the park attracted approximately 90,000 visitors per day, 30% of them from outside the metro­politan area.
  • A 2005 study by the Seoul Development Institute found that land values of adjacent parcels had increased by an average of 30%.
  • While before and after traffic counts for the corridor were unavailable, the number of vehicles passing through downtown de­creased 9% after a bus rapid transit system and aggressive Transportation Demand Management measures were implemented as part of the project.
  • Summer temperatures in the park, accord­ing to project planner Kee Yeon Hwang, are 7 degrees lower than at locations a quar­ter-mile away.
  • While two historic bridges were restored (the GwanggyoBridge had been hidden un­der the highway, while the SupyogyoBridge had been relocated to a park), construction was delayed by a lawsuit claiming that an accelerated timeline had resulted in destruc­tion of archaeological assets.
  • An estimated 1,200 street vendors were dis­placed by the project. Many were relocated to a flea market at a nearby stadium; how­ever, in 2007 the stadium was demolished, and plans were made for yet another new market nearby. 


Seoul Metropolitan Government

Heart and soul of the city, The Guardian, Nov. 1, 2006 (UK)

Public Transport Reforms in Seoul: Innovations Motivated by Funding Crisis. John Pucher, HyungyongPark, and Mook Han Kim, RutgersUniversity; Jumin Song, University of Michigan

Case Study Source: Department of Transportation, City of Seattle

Leave a Reply

Your email address will not be published. Required fields are marked *