The social significance of the Four Major Rivers Project involved a great many matters to be discussed from many angles: not only the conflicts of interest it would create, but also potential environmental problems; the efficiency issue that an excessive budget relative to its purpose would make it a project worse than doing nothing; the lack of grounds for the expected reduction in unemployment through job creation; disaster-prevention effects; controversy over deteriorating water quality; changes before and after surface surveys of cultural heritage; where and how to save and allocate the enormous budget; soaring vegetable prices due to crop damage; and a decline in the food self-sufficiency rate. Had it gone through the ordinary process of legislation by the National Assembly, all these issues should have been considered, refined and revised, and handled on the basis of content and a budget suited to today's Korea. To prevent this, there were protests by many civic groups and lawmakers who had interests at stake or were concerned, and the well-known current-affairs programs PD Note and Chuchuk 60 Minutes had scheduled broadcasts that were suddenly cancelled. Under these circumstances, suspicions gradually grew that the efforts that should have gone into passing the bill directly had been spent elsewhere. Moreover, as a result of abusing delegated legislation to finally pass the Four Major Rivers Project, the bill was passed through delegated legislation without sufficient discussion, arbitrarily taking budget that should have been used elsewhere. It was also enough to provoke public anger that, as controversy over the project grew, it was linked to the Grand Canal project and the two were treated as separate matters, used as a tool to ultimately steer things in the desired direction.

This is drawing strong criticism that, rather than trying to resolve the Four Major Rivers issue quickly because it was important and urgent, the aim was to get good results in judgments about what achievements had been made within the term of office. This issue drew intense reactions and interest not only in Korea but also from foreign media. Critics have argued that the Four Major Rivers Project, with unclear purposes, is a clearly environmentally destructive project that violates the Ramsar Convention and the Convention on Biological Diversity and must be stopped. Ryoichi Hori, Japan representative of the Ramsar Network, "said strongly that Korea hosted the 2008 Conference of the Parties to the Ramsar Convention and promised to protect the world's wetlands, so destroying wetlands like this is unthinkable and must be stopped immediately." Afterward, the Ministry of Land, Transport and Maritime Affairs tried to prove the project's results by issuing a press release saying it contributes greatly to job creation and revitalizing local economies, but even now, as of 2016, attempts to properly assess the economic ripple effects of the Four Major Rivers Restoration Project appear to have produced no notable results.

For reference, Article 75 of the Constitution provides that the President may issue Presidential Decrees on matters delegated by statute with their scope specifically defined, and Article 95 provides for Prime Ministerial Decrees and Ordinances of Ministries. Where whether orders or rules violate the Constitution or statutes is a premise of a trial, the Supreme Court has final review (Article 107(2) of the Constitution), and Article 98-2 of the National Assembly Act requires enforcement decrees and the like to be submitted to the competent standing committee of the National Assembly. The policy assessments and media reports in the material are the author's summary, so when citing them in an assignment check the original texts and provisions directly.