Recent history shows us that, for the sake of achieving a higher rate of economic development, humanity has consistently neglected the consequent environmental degradation.

As the dire state of our environment and the urgent need to protect it has gained greater attention the subject has grown increasingly controversial, both uniting nations in the shared experience of environmental damage and dividing them in how to deal with it.

In a five-part series that travels from the timber docks of China to the mountain ranges of America, Assignment Earth looks at just a handful of the many pressing issues confronting our fragile world.

Part Four

Damning the Mekong

When water is released it raises the level down river causing a destuctive force
Throughout Southeast Asia, farmers and fishermen complain that China's thirst for hydroelectric power is choking the Mekong, a waterway that sustains about 70 million people.

China has completed two dams across the river, with two more under construction and four others planned.

Indiscriminate Chinese releases of water have fatally altered fish breeding cycles that depend on seasonal changes of water levels. 

Assignment Earth travels to Thailand where we see the growing environmental troubles being faced as a result downstream, including lower water levels, less nutrient-rich sediment and degraded fisheries.

Guided by a specialist on this subject, we meet the families of fishermen and farmers and speak with government officials and scientists who attest to the critical problems caused by the serial blockage of the river upstream.

Crops are eroded and destroyed down river
On the Salween river, the longest undammed river in Southeast Asia, several huge dam projects are planned in China, Burma and Thailand. 

People living on the Salween, tell us of their fears for the future if their river is altered like the Mekong.

In this episode we see how impoverished families are already affected by dams on the Mekong and better understand how more dams will affect not only the Mekong but also the pristine Salween.

Part four of our five part series aired 23 June 2007 at the following times:

Saturday 23 June 2007 (14.30, 22.30 GMT)
Sunday  24 June 2007 (02.30,12:30 GMT)
Monday 25 June2007 (07:30 GMT)
Tuesday 26 June 2007 (07.00, 13.30 GMT)
Wednesday 27 June (11.30, 20.30 GMT)
Thursday 28 June (05.30, 19.30 GMT)
Friday 29 June (03.00, 16.30 GMT)
Saturday 30 June 2007 (06.30 GMT)

Watch Part One here:

Watch Part Two here:

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