Seoul's 'Sinsangdo Underpass' to Expand and Reopen on 24th... Expected to Improve Yangnyeong-ro Bottleneck Situation

Connection from Sangdo Station (Line 7) to Guksabong Tunnel (Sangdo-dong), 221m extension, expansion from 2 to 4 lanes
Average travel speed increased from 11.2 to 24.7 km/h... Bottleneck resolved, habitual traffic congestion expected to decrease

[Asia Economy Reporter Lim Cheol-young] Seoul City announced on the 23rd that it will open the ‘Sinsangdo Underpass,’ the only remaining two-lane section on the 2,450m stretch of Yangnyeong-ro connecting the northern end of Hangang Bridge to Nambusunhwan-ro, expanded to four lanes in both directions, on the 24th.

The ‘Sinsangdo Underpass,’ which connects Sangdo Station (Seoul Subway Line 7) and Guksabong Tunnel (Sangdo-dong, Dongjak-gu), is expected to reduce habitual traffic congestion by eliminating the bottleneck that caused traffic jams during rush hours with the opening of four lanes in both directions. The average travel speed during rush hours is expected to increase by 13.5 km/h, from 11.2 km/h to 24.7 km/h.

The long-awaited project by local residents, the ‘Sinsangdo Underpass Expansion Project,’ overcame numerous obstacles and reached completion two years after construction resumed, opening as a four-lane road in both directions. The upper road maintenance work will be completed by April next year.

A total of 42.2 billion KRW was invested, with the underpass extended by 221m and expanded to four lanes, and the surrounding roads and upper road improved. A 1.7m-wide pedestrian walkway was installed inside the underpass to enhance walking convenience for vulnerable road users. Additionally, transparent soundproof walls were installed between the walkway and the roadway to avoid visual claustrophobia, and by completely separating the walkway from the roadway, exhaust fumes and fine dust were blocked.

In particular, the height inside the underpass (box section) was raised to about 6.0m to provide drivers with a wide field of view and a sense of openness. Safety facilities were expanded to prevent road accidents and ensure safe driving, including the installation of heating wires to prevent road freezing and grooving to prevent slipping.

Lee Jeong-hwa, head of Seoul City’s Urban Infrastructure Headquarters, said, “Not only Yangnyeong-ro but also surrounding roads such as Sangdo-ro and Euncheon-ro will see improved vehicle travel speeds and reduced congestion during rush hours, which is expected to greatly contribute to regional development.”

This content was produced with the assistance of AI translation services.