Environment: The builders who were dammed

"I came, I saw and I was conquered," said President Roosevelt when he inaugurated the Hoover Dam in 1935. Few Western leaders would be likely to repeat such gushing enthusiasm today. Worldwide, huge dams have become increasingly controversial.

One of the most famous dams of all time was the Aswan Dam in Egypt in the 1950s, where the West and the Soviet Union vied with each other to finance the expensive project, and thus gain political influence. The Russians won. At the time, the project was enormously popular. Crowds chanted: "After the dam, our land will be paradise." But the project brought few benefits, in the longer term.

Elsewhere, opposition to large dams has had dramatic consequences. Conservationists in Tasmania failed to prevent the government creating the Pedder dam in the 1960s. In 1983, however, crowds forced a retreat on proposals to build a dam close to the junction of the Franklin and Gordon rivers, which would have flooded a wilderness area. More recently, there have been moves to restore the environmentally unique Lake Pedder, by draining the reservoir which the dam created.

In eastern Europe, the popular resistance to dams played a key early role in creating the mass movements which ended the Communist era. The Gabcikovo dam on the Danube was approved by the Communist authorities in Hungary and Czechoslovakia. But a huge environmentalist movement in Hungary - the biggest opposition since the uprising of 1956 - forced the government to back down, in 1988. The retreat marked the first sign that crowds could force even an authoritarian regime on to the defensive. Within a year, demonstrations in East Germany, Czechoslovakia and elsewhere ended one-party rule throughout the region.

More recently, dams have remained highly controversial. The Pergau dam in Malaysia was heavily funded from the British aid budget, so that the taxpayer subsidised British contractors. An official condemnation by the National Audit Office forced the Government to back down, in 1993. The adventure does not seem likely to be repeated.

- Steve Crawshaw