"I should like to hear," said Duke Huan,
"about the harmful effects of water"
Kuan Chung replied
"...It is the nature of water to flow, but
when it reaches a bend [in the channel] it is retarded
and when the bend is full [the water] is impeded.
[In some places] where the bank curves [the water] pounds against it and crumbles it away;
[in other such places][the water] becomes agitated and leaps up.
When it leaps up it runs to one side.
On running to one side it formss whirlpools.
After forming the whirlpools it returns to its central course.
On returning to its central course [and slowing] it deposits its silt,
and when this has occurred [the channel] becomes obstructed.
Obstruction leads to a change of course.
Change of course brings fresh stoppage.
Thus impeded, the river runs wild.
Running wild, it injures men.
When it injures men, there arises great distress among them.
In great distress they treat the laws lightly.
Laws being treated lightly, it is difficult to maintain good order.
Good order lapsing, filial piety disappears.
And when people have lost filial piety, they are no longer submissive."
(from Needham Science and Civilization in China 4:3:223)
and from the same source, pg. 295:
And here's another glimpse of the Realities:
Fields that have no access to creeks cannot be drained if flooded, and cannot be watered if dry. It is hard to bring manure to them and to remove the harvest. these fields are mostly owned by poor people in distressed circumstances who should be treated with compassion. Fields which abut on a creek or lie along its length, are easy to irrigate when dry and easy to drain when flooded. Manure can easily be brought to them and the harvest can easily be taken away. These fields are mostly owned by rich and powerful persons.
Gu Yanwu, quoted in Mark Elvin Another History pg. 105 (DS735 .E47 1996)