Huayuankou in Henan marks the starting point
of the river's lower reaches. It is a vulnerable spot
for floods, where the river gradient diminishes
rapidly downstream causing flood water to back up
and raising the high-water level here.
Before the flood arrives, the river's flood plain
is calm and dry, as shown in the top picture.
Harvest from the flood plain depends on the magnitude
of the river's runoff during the flood period.
Roughly once in ten years the entire flood plain
would be submerged.
Nowadays, miles and miles of dikes line both shores
of the river along its lower reaches.
Thousands of people are mobilized to
combat flood each year
between July and August.
Picture source: YRCC, Huanghe Feng,
Yellow River Pub House, 1996.
