A similar proposal from the Song engineer Li Chun concerning flooding the lower reaches of the river to protect the central plains from the Khitai was overruled in 1020: the Chanyuan Treaty between the two states had expressly forbidden the Song from establishing new moats or changing river courses.
Unha proposta semellante do enxeñeiro Song Li Chun para inundar as partes baixas do río e protexer así as chairas centrais dos Khitai foi revogada en 1020: o Tratado de Shanyuan entre os dous estados prohibira expresamente aos Song establecer novos fosos ou cambiar o curso do río.