HUANGTUPO VILLAGE, China - Wang Zhushu rarely sleeps at night. Instead, the 61-year-old retiree paces, listening to the drone of passing ships that shake the walls of her house on the banks of the Yangtze River.

Wang's one-story, brick-and-concrete house rests, she says, on increasingly unsteady earth, weakened and waterlogged as rising waters turn the Yangtze into an ever-broadening reservoir behind China's mammoth Three Gorges Dam.

"The house has become crooked. Water seeps through the floor and there are cracks growing here, here and here," said Wang, pointing to the ceiling, a storeroom, and a rock wall with crevices three fingers wide. At night, "I can feel the vibrations. I walk around and around the room, and I worry."

For millions of Chinese living along the reservoir's shores, the dam that the government said would give them a new life is stirring fresh concern.

Four years after the waters began rising in the 410-mile-long reservoir, villagers tell of warped foundations and fissures snaking along the earth. Pollution in the once fast-running river is building in the now-turbid reservoir. Landslides, common in the rainy region, are occurring more frequently. The ships are nothing new, but now they are one more reason for Wang to worry.

The $22 billion dam - the world's biggest hydroelectric project, due to be completed in 2009 - was supposed to end flooding along the Yangtze and provide a clean-energy alternative to coal.

Yet along the way, more than 1.4 million people had to be moved. Though critics and experts warned the environment and people would pay too high a price, their criticisms were ignored and suppressed by a government in thrall to large engineering projects.

Now, even a few officials are breaking ranks to predict catastrophe. Toxic algae are blooming, feeding off industrial waste and sewage, and tainting water supplies.

Experts have warned that the waters in the enormous reservoir are undermining hillsides. Water seeps into loosely packed soil and rocks, making them heavier and wetter. It can trigger landslides on steep slopes like those rising from the Yangtze.

Additionally, the huge weight of the water on the bedrock exerts a pressure that could lead to earthquakes. Chinese officials have denied it could happen here, but some observers are unconvinced.

How the communist government deals with these problems has become a test for the Communist Party leadership headed by President Hu Jintao, who has promised to deliver more compassionate, responsive and environmentally sensitive government.

In September, state-controlled media ran rare admissions by officials about the problems.

Wang Xiaofeng, deputy director of the Three Gorges Project Construction Committee, was quoted as saying China risked disaster. Vice Mayor Tan Qiwei of Chongqing, a sprawling metropolis next to the reservoir, told of 91 reported landslides along 22 miles of shoreline.

"The ecological situation in Three Gorges areas is worse than I expected," said Chen Guojie, a professor with the Institute of Mountain Hazards and the Environment at the government-backed Chinese Academy of Sciences. He ticked off a list of worries - tremors, erosion and pollution - and said the social impact was equally grave.

"Farmers lost their land and moved to new towns, but these towns had no industry and there were not enough jobs," he said. "So many of the young farmers were forced to leave their homes and work in other cities."

As criticism has mounted in recent weeks along with the problems - a landslide in the region killed at least 34 people last month - the government has launched a renewed public-relations campaign stressing the project's benefits.

Beijing also says it will shore up the area's environment with new measures to control pollution, close industrial and mining enterprises, and monitor geological hazards. Meanwhile, local governments are relocating the tens of thousands of people living in dangerous areas.