TANGJIASHAN/MIANYANG, Sichuan, May 26 (Xinhua) -- Rescuers are preparing to dynamite the barrier of a swelling earthquake-induced lake at risk of bursting and threatening thousands of people downstream in southwest China.

Experts have proposed a water diversion channel to drain Tangjiashan Lake, formed by landslides that blocked a river known as the Jianhe after the May 12 earthquake in Sichuan Province.

Tangjiashan, one of 35 such lakes, is inaccessible by road and can only be reached by foot or air.

The water level in the lake rose by 1.6 meters on Monday, a slowdown in recent days, a hydraulic expert at the local observation site was quoted by the People's Daily Online.

Helicopters have airlifted professionals and materials for the operation to the blockage at the barrier lake in Beichuan County, Sichuan.

Sunday's adverse conditions hampered the operation, but the weather and visibility were fine on Monday morning, said a spokesman with the Mianyang Airport Headquarters for Quake Relief Flight Operation.

The weather around the lake area turned favorable on Monday and a predicted rain at night would not hamper the flight, according to officers at the site.

"Around 100,000 (people) would be evacuated to ensure the safety according to the current draining plan," Liu Ning, Ministry of Water Resources of China chief engineer, told the Shanghai-based Oriental TV.

"It's better for them to complain about the trouble that the evacuation would bring than to shed tears after the possible danger," he added.

A Mig-26 helicopter transported a large bulldozer from Leigu, near Tangjiashan, which can only be reached on foot or by air. By 7 p.m. on Monday, more than 10 diggers and bulldozers and 40-plus tons of relief materials, including tents, drinking water, food and gasoline, had been airlifted to the site.

Meanwhile, a contingent of armed police arrived on foot early on Monday to help with the task of draining the lake. They were to work on the barrier if bad weather and low visibility continued to hamper flights.

The armed police were part of the 1,800-strong force, including People's Liberation Army (PLA) personnel, who started hiking on Sunday toward the lake, 3.2 km upstream from the Beichuan County seat, from which thousands of quake survivors had been evacuated since Wednesday.

A PLA officer told Xinhua the soldiers each carried 10 kilograms of dynamite and planned to carry out small scale blasts to drain the rising water.

The lake dam is in danger of bursting after water levels rose by almost two meters on Saturday to 723 meters, only 29 meters below the lowest part of the barrier that reached 752 meters.

The risks were heightened as high winds and thunderstorms were forecast for the area on Monday and Tuesday. In addition, it was hit by a strong tremor measuring 6.4 on the Richter scale on Sunday.

The lake is currently holding more than 128 million cubic meters of water and could cause a devastating flood threatening the lives of 1.3 million residents in adjacent areas if the barrier bursts.

More than 30,000 residents downstream of Tangjiashan lake have been evacuated to higher ground, according to the Mianyang City government.

Altogether, 35 barrier lakes were formed by landslides after the quake that left 65,080 people dead and 23,150 others missing as of Monday noon, according to the Information Office of the State Council.

Professionals and materials are airdropped for operations to blow a barrier lake at Tangjiashan, Beichuan County, which was formed by landslides after the May 12 earthquake and now blocks the river Jianhe.(Xinhua Photo)

Source: Xinhua