A five-minute walk from Daecheong Station on Seoul Subway Line 3. A flat site of 393,000 square meters spreads out in the heart of Gangnam District, Seoul. It is the Tancheon water reclamation center that Seoul Mayor Oh Se-hoon proposed as an alternative to housing supply at Yongsan Park, suggesting building up to 13,000 dwellings. It has the advantage of being a large site near a station area, but the facility that treats up to 900,000 cubic meters of sewage a day must be moved first. Preserving the existing park and securing a replacement site must also be resolved, so actual housing supply could take close to 10 years.
The Tancheon water reclamation center visited on the morning of the 26th looked more like a park than a sewage treatment plant from the outside. After walking about four to five minutes from Daecheong Station, Maru Park appeared with walking trails threading through thick trees. A lawn square, children's play facilities, and sports facilities were also in place. If one did not know there was a large-scale sewage treatment facility, it looked no different from any neighborhood park in Gangnam.
Going deeper into the park revealed the scale of the facility. A signboard said it was 550 meters to the main building and the first treatment plant, and 1 kilometer to the second treatment plant. Beyond the fence along the edge of Maru Park, water treatment facilities stretched out in a long row. The park used by residents and the large-scale sewage treatment facilities sat side by side in the same space.
The Tancheon water reclamation center sits around 625 Gaepo-ro, Gangnam District. The site area is about 393,000 square meters, larger than the roughly 300,000-square-meter Yongsan Children's Garden. Completed in 1987, it has been operating for nearly 40 years and treats sewage generated across Gangdong and Songpa districts and parts of Gangnam and Seocho districts, and Hanam and Gwacheon. Its maximum daily treatment capacity is 900,000 cubic meters.
Residents around the water reclamation center have raised odor issues in summer and early fall. However, while looking around Maru Park and the treatment facilities this morning, there was no smell strong enough to make walking difficult. As it was a weekday afternoon, there were not many park users, but residents out for a walk or using sports facilities were seen here and there.
On this day, the mayor officially proposed at a second meeting with Minister Kim Yun-duk of the Ministry of Land, Infrastructure and Transport the transfer of the water reclamation center and the creation here of a residential and industrial complex for up to 13,000 households.
Seoul city put forward the Tancheon water reclamation center as an alternative due to its locational conditions. It is in a station area at Daecheong Station and also close to Suseo Station and the Suseo interchange. It is rare in the Gangnam area to secure a flat site of this size all at once.
After the transfer of the center, Seoul city is reviewing a plan to build dwellings on about half the site and place parks and research and development facilities for physical artificial intelligence (AI), such as robotics, on the rest. The idea is to supply a minimum of 10,000 to a maximum of 13,000 households and create a tentatively named "Southeast youth specialized industrial complex" where young people can solve both housing and jobs together.
The problem is that the upper area of the center is already used as a living space for residents. To create a housing complex, it must be decided how much of Maru Park and the sports facilities will be kept and where to relocate the facilities to be demolished.
A resident in their 70s, identified as A, who was walking in Maru Park, said, "I walk here every day," and added, "Even if apartments are built, I hope the park used by residents is kept."
The biggest hurdle is preparing replacement facilities to treat 900,000 cubic meters of sewage a day. Securing a transfer site and building new facilities, persuading residents in the relocation area, and going through administrative procedures must all be completed. Seoul city expects the transfer of the water reclamation center to take four to five years, followed by another roughly four to five years for housing construction. Even if the plan proceeds as scheduled, it means supplying housing in the short term is difficult.
Seoul city is aiming to complete the eligibility study for the center transfer project by the end of this year. Mayor Oh also explained to the Minister that selling nearby city-owned land would raise about 5.5 trillion won and that the city would attract private capital.
The Ministry of Land, Infrastructure and Transport (MOLIT) has not yet decided whether to develop the Tancheon water reclamation center. When Seoul city submits project materials, it plans to review the supply volume, business feasibility, and transfer plans. The Minister said, "We had a conversation with the intent to review it actively."