Cost-benefit ratio for Incheon subway Line 1 Songdo extension drops from 0.9 to 0.3, Park Chan-dae transition team criticizes previous administration's feasibility study

Questions are mounting over the credibility of the planned extension of Incheon subway Line 1 into Songdo Section 8, after the project's cost-benefit ratio came in far below the city's own figure during the national pre-feasibility review process.

The transition committee for Incheon Mayor-elect Park Chan-dae said Monday that after analyzing results from the first joint review meeting between the Korea Development Institute (KDI) and Incheon city on the pre-feasibility study, the cost-benefit ratio had fallen from the city's stated figure of 0.9 to approximately 0.3 under KDI's assessment.

According to the transition committee, the total project cost rose from the city's estimate of 419.3 billion won ($272 million) to 472.6 billion won under KDI's review — an increase of 53.3 billion won — while projected benefits shrank from 27.1 billion won to 11.9 billion won, a decrease of 15.2 billion won.

With costs rising and benefits falling, the cost-benefit ratio dropped to roughly one-third of the city's original projection.

The transition committee criticized the administration of Mayor Yoo Jeong-bok, saying the approximately two years and three months of feasibility work and pre-feasibility preparation his office conducted fell short of KDI's objective verification standards.

The committee also said KDI's demand for additional traffic-impact-level demand data related to the Golden Harbor development project was a further sign of insufficient analytical reliability.

Park Chan-dae said the Songdo Section 8 extension was an essential project for residents' transportation convenience and the development of Songdo International City. "After the launch of the ninth elected administration, we will responsibly push to pass the pre-feasibility study by thoroughly incorporating KDI's supplementary requirements and working closely with relevant agencies," he said.