The dam here is a mass of weathered concrete, rusting steel fixtures,
and old-fashioned power pylons, set in a narrow valley of tawny rock.
Ticket-sellers and souvenir shop staff spring to life when a rare
foreign visitor joins a small number of Chinese sightseers paying to
walk across the top.

When the Sanmenxia dam was completed in 1960, after three years in
construction under Soviet supervision, it was hailed as a symbol of the
new revolutionary China and its image printed on the country’s
banknotes. The first dam on the Yellow River, it signalled man’s
impending triumph over a nature that regularly brought floods to
millions of villagers.

Now, there is debate about whether the dam should be opened and the
river waters allowed to run free. The hydro-electric plant that now
hums below the dam should be written off, and a nearby aluminium
refinery supplied with power from cheaper thermal sources.

This argument is put by Professor Zhang Guangdou, the 92-year-old doyen
of China’s hydraulic engineers, who said recently on national
television that the dam should be pulled down before it caused more
flooding upstream. He is backed by Shaanxi province, which has been
menaced by flood waters backing up the Wei River, a tributary that
joins the Yellow River just above the dam, as far as the historic city
of Xian.

“Sanmenxia was a mistake,” said Professor Zhang, revealing that other
Chinese experts had doubts about the project but were silenced because
of reverence for Soviet leadership. One eminent hydrologist who
attacked the project, Professor Huang Wanli, was denounced as a
“rightist” and sent off for years of hard labour. He died in 2000 at
the age of 90.

The problem is the massive silt load of the Yellow River, 60 times
greater than that of the Mississippi, from the soft earth found in the
region upstream. Within four years of opening, the dam had lost 40 per
cent of its water storage capacity because of silt, and its
Soviet-built turbines were clogged.

Beijing began remedial work that is still going on.

Now the dam has less than 10 per cent of its original storage capacity,
and its spare capacity to hold water in the late summer flood season is
relatively insignificant. The 400,000 villagers who were evicted and
transferred to bleak Ningxia and Inner Mongolia are wondering about the
sacrifice they have made, as are upstream farmers whose land has been
spoiled by salt flushed up by a rising water table.

The hillsides around the reservoir remain a picture of hardship, of
tiny wheat fields on the ridges and terraces of an eroded landscape, of
houses that are mostly caves in cliff-faces fronted with a brick
facade. The dam’s powerhouse generates only about 25 megawatts,
compared to the 1160 megawatts planned by the Soviet experts.

Sanmenxia has become a case study in what can go wrong in a big dam; how dubious the claimed benefits are in some cases.

It was cited in the vain opposition to the vastly bigger Three Gorges
Dam on the Yangtse River, whose reservoir is now said to be turning
into a toxic mix of human and industrial waste.

It is also used to argue against the new Xiluodu project on the Jinsha
River, which is China’s next largest dam, where many thousands of
villagers have been violently evicted this year.

According to a spokesman of Leibo village, who brought their grievances
to Beijing last month, local officials have seized land not needed for
the dam.

Perhaps because of this, China’s hugely powerful hydro-electric
establishment is refusing to accept that Sanmenxia was a mistake. It
managed to water down a Shaanxi resolution calling for the dam to be
demolished.

The Ministry of Water Resources has just announced a “comprehensive”
scheme to flush away sediments and shore up the Wei River embankments,
at a cost of 25.31 billion yuan ($4.4 billion) between now and 2010.

Sanmenxia is proving a costly socialist icon.