Police are urging people to stay away from Whaley Bridge as the operation to secure the dam at Toddbrook Reservoir continues.
In a statement issued this morning, the force said there was still a risk the dam will fail, but that teams would be working throughout the day to further shore up the reservoir wall.
Assistant Chief Constable Ken Mehmet said: "Our message today remains the same -- as there is still a risk the dam will fail – please stay away from the area.
“If you are asked to leave, please heed emergency services and expert advice and do so. We understand that being asked to leave your home is an extremely difficult and worrying situation to find yourself in, however it is not a decision we have taken lightly and ultimately the safety of the public is our main concern.
“The evacuation point at Chapel High School, Long Lane, Chapel-en-le-Frith, High Peak, SK23 0TQ, will remain open today and residents will be accommodated if they are unable to make alternative arrangements.
“We have evacuated more than 1,000 people from the areas that would be immediately affected by floodwater should the wall fail.
“The majority have been able to find accommodation with family and friends. About 40 people have also been put up in a local hotel and they will be looked after today.
“We don’t know how long this operation will take to conclude but we and our colleagues in the emergency services, partner agencies, Environment Agency and military are doing everything humanly possible to save the reservoir wall and to protect the town.”
Police have been assisted overnight by partner agencies including the fire service who have sent firefighters from across the country, the Environment Agency, the ambulance service, local councils and emergency planning staff.
RAF crews have also been using a Chinook helicopter to move more than 50 tonnes of aggregate into the reservoir wall to reinforce it.
This work was done in conjunction with expert structural engineers, who have been advising the emergency response since yesterday afternoon.
Throughout the day, work will continue to further shore up the reservoir wall. The Chinook will also be dropping aggregate into other parts of the reservoir today, to stem the flow of water going into it.
There are also a total of 16 high volume water pumps which have been installed in the reservoir, in order to reduce the water levels. These have been provided by fire services from across the country and the Canal and River Trust.