Shanghai is Sinking

S H A N G H A I,  China, July 28 -- The only thing keeping the Huangpu Riverout of the Peace Hotel’s Art Deco lobby on Shanghai’s waterfrontthis summer is a concrete flood wall.

It’s not that the river has risen more than usual during therainy season. Instead, Shanghai is sinking.

The land under the skyscrapers and 13 million people of thisbustling metropolis is deflating like a giant air mattress, slowlysettling as its shallow water table collapses after decades ofoveruse.

Sinking Widespread

Sinking cities are common in chronically dry China, which isguzzling water from underground aquifers to supply a boomingeconomy and growing population.

Land under 46 cities is sinking, the government says. Areasaround Beijing, the capital, have sunk by up to 14 inches over thepast decade.

Although Chinese officials warn publicly about relying tooheavily on wells, drought in recent years has complicated theirefforts. As rivers dry up, cities and farms drill more wells. Morethan 100 cities in northern China are short of water, the officialXinhua News Agency has reported. Some reservoirs are dry.

Shanghai has switched to river water for most uses, slowing itsannual descent to less than two-fifths of an inch. But after yearsof rapid decline, even that threatens China’s business capital,which sprawls across flat land less than 10 feet above the Huangpu.

“If we didn’t control this, the ground would collapse” bythree feet every decade, said Liu Yi, a government geologist whotracks the sinking. “The damage would be unbelievable — floods andwrecked buildings.”

Drained Water

Shanghai, one of the world’s most densely populated cities,switched fairly easily to water from the Huangpu and Yangtzerivers. But it still suffers the legacy of long, severe bouts ofground subsidence.

The problem stems from Shanghai’s rapid 19th centurymetamorphosis into a foreign colonial base. Shallow aquifers thathad supported a Chinese trading port were quickly strainedsupplying factories and a populace that tripled by 1900 to morethan 1 million.