These dramatic pictures show how more of the Toddbrook Reservoir dam wall is crumbling away.
Around 400 homes in the lower valley area of Whaley Bridge were was issued.
It came after a massive emergency response was launched when a section of the dam wall collapsed following heavy rainfall and flooding.
Now latest images from the scene appear to show more of the dam wall has broken away.
Several more of the large concrete panels which form the wall have slipped into a muddy void which has formed beneath the affected area.
A landslip seems to be taking place on the grass slope next to the dam wall.
Emergency workers can also be seen forming a human chain on top of the wall as they lay sandbags in the battle to prevent further damage.
Those evacuated have been told to stay with family or friends, with others being sheltered at Chapel High School in nearby Chapel-en-le-Frith.
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Tonight engineers are assessing the stability of the dam. Police are warning people to stay away from the area.
Water is being removed from the reservoir and being pumped into the River Goyt below to relieve pressure on the wall.
