[Seoul's Future] "Road Undergrounding Must Be Considered Carefully for Safety"

Bypass Roads Instead of Full Undergrounding as an Alternative
Provide Incentives to Reconstruction Associations Along the Hangang River
Encourage Bypass Routes Like Jeoldusan Holy Site

[Asia Economy Reporter Hwang Seoyul] Jin Heeseon, Specially Appointed Professor of Urban Engineering at Yonsei University, identified three essential changes needed for Seoul: ▲safety ▲jobs ▲housing issues. However, she did not view these problems as challenges that only the public sector must solve. Especially regarding the job issue, she emphasized that the public sector should not be the supplier but rather provide pleasant infrastructure such as housing, transportation, and parks to enable the private sector to supply jobs autonomously. At the same time, she expressed a cautious stance on the recent active discussions about underground roads.

Professor Jin served in the Seoul Metropolitan Government for 32 years until her retirement as the 2nd Deputy Mayor of Seoul in 2020. During her tenure, she held positions such as Director of the Housing and Architecture Bureau and Head of the Urban Regeneration Headquarters, personally experiencing the policy-making process encompassing the entire city of Seoul, including New Town projects, housing supply, and urban planning and management. Based on this experience, she authored books on Seoul’s urban space such as ‘Spaces Coveted by Power: Blue House, Gwanghwamun, Yongsan’ and ‘Black Hole Gangnam Apartment Nation.’

-There have been many ideas about undergrounding roads such as Gangbyeonbuk-ro, Gyeongbu Expressway, and Olympic-daero. What are your thoughts on this?

▲I oppose undergrounding all arterial roads. I think we should try one or two first, thoroughly review them, and then consider moving forward. When talking about underground roads, the most frequently cited example is Boston’s ‘Big Dig’ project. However, driving through the underground roads is extremely claustrophobic. Traffic jams occur, the space feels enclosed, and water drips down the walls. It also raises safety concerns in case of an earthquake. Since safety is increasingly emphasized, we must consider extreme scenarios during the planning stage. For example, what if an oil-fueled vehicle enters and causes an accident? What about claustrophobia during traffic congestion? Considering all these factors would cost trillions of won, so we must also consider whether we can bear such costs.

※Big Dig Project: Meaning ‘digging deep into the ground,’ this project was carried out in Boston, Massachusetts, USA, to alleviate traffic congestion and redevelop the downtown area for the 21st century. It expanded a 6-lane road connecting about 26 km between Boston’s outskirts and downtown to 8-10 lanes, replacing elevated roads with underground roads to create parks and green spaces. The project started discussions in 1982 and took about 25 years to complete in 2007.

Former Seoul Deputy Mayor for Administration Jin Hee-seon, a special professor in the Department of Urban Engineering at Yonsei University, is walking through the back alleys of downtown Gangnam, Seoul. Photo by Heo Young-han younghan@

-How should we approach future road planning?

▲Considering the speed of societal change, we need to proceed with a long-term plan. The trend is increasingly toward pedestrian-centered and public transportation-centered systems. If there is a total road volume in a city, in foreign countries, the space ratio occupied by pedestrians and cars is about half and half, but in Seoul, the car ratio is high. Manhattan also appears to have a high car ratio, but pedestrian sidewalks along Times Square and Broadway are gradually expanding. In Madrid, Spain, all lanes are two lanes each way, and four lanes each way only in unavoidable cases. The rest is pedestrian-friendly. In contrast, Gangnam seems to have only major roads. Also, with autonomous vehicles, machines will connect and move by themselves, increasing speed compared to now. If such an era arrives in 10 years, undergrounding might become unnecessary.

As we move toward autonomous driving, pedestrian-centered, and public transportation-centered systems, we must consider whether it is truly appropriate to underground major roads and whether they are suitable for undergrounding, taking into account technological speed and urban lifestyle. Policies declaring ‘because traffic volume is high, we will underground and build apartments on the remaining land’ could cause problems.

-Are there alternatives to fully undergrounding roads?

▲We can consider bypass roads like Jeoldusan Holy Ground. For example, passing through the Namsan Tunnel briefly is fine, but if you think about traveling over 16,000 km underground and encountering congestion, it becomes a serious problem. Instead of fully undergrounding roads, creating several bypasses would be better.

On September 8th, the first day of the Chuseok holiday. The Gangbyeonbuk-ro heading towards Guri, as seen from Seogang Bridge in Seoul, is congested with vehicles of holiday travelers. Photo by Jinhyung Kang aymsdream@

-What methods can realize this?

▲There are many reconstruction and redevelopment complexes along the Han River, and I think it would be good to encourage road construction such as bypasses or underpasses by providing incentives to maintenance project associations. Besides these areas, many complexes are adjacent to streams; for example, if housing price issues are resolved, it would be great to connect the Mokdong reconstruction complex with Anyangcheon. There is some regret about the Banpo reconstruction complex right in front of the Han River; it seems possible to create such roads in front to connect with the Han River.

If resources are limited, bridges are also an option, and pursuing diversity in connections would be much better. I dream of a city where cars coexist rather than being excluded. Rather than grand changes all at once, actively encouraging reconstruction associations with incentives would be good. It won’t happen overnight, but if we don’t start thinking about it now, we won’t be able to do it even after 10 years.