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우리나라의 하천, 특히 4대강은 모두 천정천이라 해서 하상바닥의 고도가 그 주변보다 높은 하천구조고 우리나라 지하수는 대부분이 천성지하수로 그 깊이가 얼마 되지 않는데 준설로 인해서 하상고도가 낮아지면 천성지하수로 갈 유역의 지하수가 4대강본류로 갈 가능성은 충분함.

다시 말하자면 지하수가 있는 높이보다 하천바닥의 높이가 높았는데 공사한답시고 하천바닥을 파버려서 하천바닥이 지하수가 있는 높이 보다 낮아지게 되면 지하수가 죄다 강으로 흘러들어간다는 얘기네요. 

덕분에 주민들은 극심한 물부족을 겪고 있는거고 이게 다 사대강 때문이다라고 주장하는 거고 국토부에서는 아니다, 니들이 농사 짓느라 물낭비를 해서 그런 거다라고 주장하는 거고요.

지금 조사중이라 하는데 여태까지 해온 짓을 봐서 제대로 조사결과를 발표할 리도 없고, 발표된 조사결과를 주민들이 믿지도 않겠죠.