Maybe it's just a change in their delivery of farm to market

[Wade]

Dead Pigs in River Not Affecting Shanghai's Water, Officials Insist - ABC News

 

[dyingsun]

Mao is long gone they say.... They'll all starve over there without any help. Pretty much like North Korea.

 

[mike]

Maybe the pigs drank the water first

• 80 of China‚ major rivers are so degraded that they no longer support aquatic life
• 90 percent of all groundwater systems under major cities in China are contaminated

So when authorities say the pigs havent made the water unsafe to drink...... they are not lying per se.

Known as the country's "mother river", it supplies water to millions of people in the north of China. But in recent years the quality has deteriorated due to factory discharges and sewage from fast-expanding cities.
Much of it is now unfit even for agricultural or industrial use, the study shows.

One-third of China's Yellow river 'unfit for drinking or agriculture' | Environment | guardian.co.uk