Sky News Think Bangladesh Never Used To Flood

Another example of Man’s intervention on Nature and the resulting effect, NOT climate change.

From ‘dirt. The Erosion of Civilisations’ by David R. Montgomery (my bold):

Today, the Chinese people overwhelmingly live on the alluvial plains

where great rivers descending from the Tibetan Plateau deposit much of

their load of silt. Flooding has been a problem for thousands of years on the

Huanghe, better known in the West as the Yellow River, a name imparted

r i v e r s o f l i f e 4 3

by the color of dirt eroded from the river’s deforested headwaters. Before

the first levees and dikes were constructed in 340 bc, the river meandered

across a broad floodplain. In the second century bc the river’s Chinese name

changed from Great River to Yellow River when the sediment load

increased tenfold as farmers began plowing up the highly erodible silty

(loess) soils into the river’s headwaters.

The earliest communities along the Yellow River were situated on elevated

terraces along tributaries. Only later, after the area became densely

populated, did people crowd onto the floodplain. Extensive levees to protect

farmlands and towns along the river kept floodwaters, and the sediment

they carried, confined between the levees. Where the river hit the

plains, the weakening current began dropping sediment out between the

levees instead of across the floodplain. Rebuilding levees ever higher to

contain the floodwaters ensured that the riverbed climbed above the alluvial

plain about a foot every century.

By the 1920s the surface of the river towered thirty feet above the floodplain

during the high-water season. This guaranteed that any flood that

breached the levees was devastating. Floodwaters released from the confines

of the levees roared down onto the floodplain, submerging farms,

towns, and sometimes even whole cities beneath a temporary lake. In 1852

the river jumped its dikes and flowed north, flooding cities and villages and

killing millions of people before draining out hundreds of miles to the

north. More than two million people drowned or died in the resulting

famine when the river breached its southern dike and submerged the

province of Henan during the flood of 1887–89. With the river flowing

high above its floodplain, levee breaches are always catastrophic.