Nearly 1 million people in China's northern Hebei province were relocated after record rains forced authorities to channel water from swollen rivers to some populated areas for storage, sparking anger online over the homes sacrificed to save Beijing.

The vast Hai River basin covers an area the size of Poland that includes Hebei, Beijing, Tianjin. Over a span of one week from late July, the region with a population totaling 110 million experienced its most serious flooding in six decades, with Hebei, particularly Baoding prefecture, the worst hit.

According to flood control laws, when basin-wide flooding causes reservoirs, the first line of defense, to exceed their limits, water may be temporarily channeled to so-called "flood storage areas" — including low-lying populated land.