Tuesday, October 29, 2013

Aral Sea and the Amu Darya River

The Aral Sea was once the world's fourth largest inland water body with a surface of 67,300 square kilometers. It supported a lucrative muskrat pelt industry and thriving fishery, providing 40,000 jobs and supplying the Soviet Union with a sixth of its fish catch.
The Aral Sea is fed by two of Central Asia's greatest rivers, the Amu Darya in the south and the Syr Darya in the north. The former is the longest river in the region, snaking through 2,414 kilometers of steppe.

In the 1950s and 60s, the  Soviet Union built an enormous irrigation network, including 20,000 Km. of canals, 45 dams, and more than 80 reservoirs, all to irrigate sprawling fields of cotton and wheat in Kazakhstan, Turkmenistan, Tajikistan and Uzbekistan. Many of the canals were poorly built, allowing water to leak or evaporate. From the Qaraqum Canal in Turkmenistan, the largest in Central Asia, it is said that up to 75% of the water went to waste.

Of the 47,750 km of interfarm irrigation channels in the basin, only 28% have antifiltration linings. Only 77% of farm intakes have flow gauges, and of the 268,500 km of onfarm channels, only 21% have antifiltration linings, which retain on average 15% more water than unlined channels.

The Amu Darya had lost so much of its flow that it no longer reached the Aral Sea. Today, it ends around about 110 kilometers away.

Photo: Corbis

Pictured above is the Amu Darya a little ways upstream from where it now ends. Deprived of a major source of its water, the inland sea shrank rapidly. In just a few decades, the Aral Sea has been  significantly reduced in size. It is now a series of smaller water bodies, with a combined volume one-tenth its original and much higher salinity due to all the evaporation.

The future of the Aral Sea, and the responsibility for its survival are now in the hands of the five countries: Kazakhstan, Uzbekistan, Tajikistan, Kyrgyzstan, and Turkmenistan. In 1994, they adopted the Aral Sea Basin Program.

The Program’s four objectives are:
- To stabilise the environment of the Aral Sea Basin
- To rehabilitate the disaster area around the sea
- To improve the management of the international waters of the Aral Sea Basin
- To build the capacity of institutions at the regional and national level to advance the program’s aims