The winners of the June 4 metropolitan mayoral and gubernatorial elections have made many costly pledges on the campaign trail to drum up support for vote. Now they are strongly advised to more closely examine the feasibility of their promises before seeking to put them into practice.

A tally compiled by the Korea Manifesto Center puts the combined costs of the projects promised by 14 of the 17 winners at 220.7 trillion won, with the central government expected to cover 101 trillion won or 46 percent of the funding requirements.

The Finance Ministry described the financing schemes of the 14 winners as “unrealistic,” citing the difficulty for the central government to raise the budget transferred to local governments.

Of the central government’s 355 trillion won in total spending this year, 115 trillion won is to be distributed to local governments. The ministry says it is simply impossible to provide another 101 trillion won to local governments over the next four years.

This means many of the development projects promised by the winners are impractical as they expect the central government to foot a significant share of their bills.

For instance, Hong Joon-pyo, the incumbent governor of South Gyeongsang Province from the ruling Saenuri Party who won reelection, has promised many large-scale schemes, including a 14 trillion won project to develop the western part of the province.

Yet the feasibility of following through with these ideas is highly dubious as Hong suggested he would rely on the central government for 74 percent of the projects’ funding requirements.

Incheon Mayor-elect Yoo Jeong-bok, a close confidant of President Park Geun-hye, also pledged many projects, which added up to 25 trillion won in costs. Stressing his connection with Park, Yoo suggested he would burden the central government with about one-third of the cost. Yet this might just be wishful thinking.

Winners from the Saenuri Party were not alone in expecting the central government to provide significant funding to implement their campaign pledges. Many winners from the main opposition New Politics Alliance for Democracy did the same.

For instance, Lee Si-jong, the incumbent governor of North Chungcheong Province who was reelected, hopes the central government will provide up to 90 percent of the funds for his 11 trillion won development projects. His hope can be described as far-fetched.

Other winners, in contrast, plan to finance their pledges mostly with funds raised by local governments, despite their limited financing ability.

Lee Nak-yon, the governor-elect of South Jeolla Province from the NPAD, plans to foot 90 percent of his 29 trillion won bill with funds from the provincial government. But his provincial government has a fiscal self-reliance ratio of 21.7 percent, the lowest among the 17 metropolitan cities and provinces.

It is natural for elected officials to seek to make good on their campaign promises. But it would be foolish to try to keep promises of questionable feasibility.

The winners of the June 4 local elections need to put their pledges through thorough feasibility tests and abandon impractical ones as early as possible, with an apology to the electorate. Otherwise, they will wreak fiscal havoc to their own local governments.