About 135,500 cu m of mud and rocks were removed from the quake lake, leaving a 475-m-long channel up to 10-m wide in the giant dam created by landslides, said Liu Ning, chief engineer of the Ministry of Water Resources and deputy director of the diversion project.
The lake's 200 million cu m of water threatened to break the dam flood the villages, towns and counties downstream, bringing more misery to those hot by the quake.
The rising water in the lake will flow over the blockage and continue its journey through the manmade canal, and that can happen as early as tomorrow, an expert team said.
The earlier plan to blow off the blockage with explosives was abandoned because the diversion channel was completed on time, Liu said.
Most of the more than 600 armed policemen working round the clock for nearly one week to break the lake's dam had left Tangjiashan, officials said.
Soldiers had carried more than 10 tons of dynamite to the site, trekking for hours on the mountains. They had to carry them back. Also sent back were garbage and surplus fuel to prevent environmental pollution.
A total of 197,477 people were evacuated to safer places till 8 am on Saturday in line with an emergency plan, said a local relief official.
Tan Li, Party chief of Mianyang and head of Mianyang city quake control and relief headquarters, had reiterated on Friday that 1.3 million people living downstream had to be evacuated to higher grounds demarcated by the government.
On Saturday night, downtown Mianyang city appeared deserted, with shops closed and several streets cordoned off. Sandbags had been stacked one upon another in front of the doors of houses and buildings along the projected flood path to prevent water from getting in.
Residents still living in the city were put through evacuation drills last week and were told that flood warnings will be communicated through signal shots and sirens.
The May 12 quake created 34 quake lakes, out of which 28 threaten to burst their banks and drown human settlements downstream.
Hu Yun, deputy director of the Sichuan provincial water resources department, said the threat posed by quake lakes would be over by June 10.
Donation management
The State Council, the country's cabinet, issued a circular on Saturday to strengthen management on donated relief material and funds. It has asked audit offices, supervision departments and the media to check against thefts.
Audit offices and fiscal departments have been told to monitor the handling of the donations by government departments and NGOs and publicize the results regularly.