No doubt the Three Gorges Dam is an incredible engineering feat. 

Its wall towers as high as a 40/50 story building and is over 2 kilometres wide. Think of the gates of Mordor. 

It holds back almost 40 cubic kilometres of water. That makes it the biggest hydro-electric scheme in the world at 22.5 Gigawatts. 

It also has a ship-lift and canal system for moving large, river-borne ships, between the dam and the downstream river. 

But it wasn't just built to store water or generate electricity. It is also meant to attenuate annual monsoon flooding. 

But it is being severely tested.  

The rains this year are regarded by China as a once in 100 years deluge. And many concerns are now arising.

Tacitly, the dam holds back sediment that is vital to downstream farms and which help to create a sponge for floods. 

That silt is now building up in the dam and displacing water, leading to faster filling and bigger outflows. 

The outflows are swamping downstream towns and cities. But the build up is also because vegetation displaced by the dam, upstream, is not there to slow down runoff water from hills. 

But there are other less tacit, more speculative concerns. 

The gradient of the dam, its construction, cracks, poor testing and a host of other concerns are being voiced. 

Its probably unlikely to collapse although a video is circulating showing projected impacts of a collapse. 

However, it has created significant problems. China's other 94,000 dams are also showing vulnerability. 

But hopefully this dreadful monsoon season will taper in August and weather outlooks are improving.  

(c) Peter Missing @ me2u2all.blogspot.com