(Corrects first three paragraphs to make clear families had moved before area was submerged)
By Prak Chan Thul
PHNOM PENH, Feb 2 (Reuters) - Floodwater released by a recently opened Chinese hydroelectric dam in Cambodia has completely submerged a village, the campaign group International Rivers said on Friday.
Hundreds of families from five villages in the northern province of Stung Treng had moved several months ago to designated project resettlement sites, before the floodwater from the dam submerged the area, the group said.
In Srekor village, site of the submerged area, 10 families relocated to a resettlement village, while 63 stayed behind, moving to forested higher ground from where they saw the waters rise steadily since December to reach the roofs of their homes.
"The thriving community of Srekor has become a silent waterworld," International Rivers said, adding that the village's farms, temple, ancestral graves and fishing grounds had been destroyed.
The 400-megawatt Lower Sesan 2 Dam, a joint venture between China's Hydrolancang International Energy Company and Cambodia's Royal Group, finally began operation in November.
About 75 meters high and 8 km (5 miles) long, the dam has taken years to build. Part of China's hydropower ambitions in the Mekong region it is aimed at generating electricity for Cambodia.
Representatives of the joint consortium could not be reached on Friday for comment.
Environmental rights groups have repeatedly warned the project would have a costly impact on the Mekong River's fisheries and biodiversity.
Prime Minister Hun Sen has labeled those who have raised concerns about the project "radical", saying that Cambodia needs to keep up with rising energy demand.
International Rivers said floodwater levels had risen up to 7 metres since the dam began operation.
Villagers in Srekor described the destruction wrought by the released floodwater.
"Vegetation such as coconuts, mango, jackfruit and pineapple trees are all gone," villager Sarun Sokhom, 61, told Reuters, adding that approximately 54 homes were submerged.
Another villager, Sut Thoeun, 41, said the water began to rise quickly during the rainy season in December.
Both villagers said that authorities had not provided help to people who had chosen to stay behind.
Stung Treng provincial authority spokesman Men Kong said the floods were expected and that villagers could still approach authorities about resettlement and compensation.
(Editing by Amy Sawitta Lefevre and Simon Cameron-Moore)
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