The owners of Toddbrook Reservoir in Whaley Bridge have moved to reassure residents - following heavy rain yesterday.
More than 1,500 residents of Whaley Bridge had to leave their homes on August 1 for six nights after the reservoir dam threatened to breach after a period of excessive rainfall.
A major round-the-clock response from the emergency services, including Derbyshire Fire and Rescue Service, Derbyshire Constabulary and the Environment Agency, managed to avert disaster and stabilise the dam wall, and residents were allowed back into their homes on August 7.
The Canal and River Trust, which manages the reservoir, said on Friday afternoon that it had received calls from worried residents - as heavy rain fell in the area.
A spokesperson for the Canal and River Trust said: "We want to assure everyone that the reservoir is near-empty after more than a billion litres of water have been pumped out.
"Water levels are many metres below the dam wall and therefore there is no risk to residents.
"In fact there is only a small amount of water left in the centre of the reservoir to keep the local fish stock alive.
"Pipes for 11 high-volume pumps remain on site - these are there to pump out any rainfall that enters into the reservoir to ensure that it remains at near empty. They have the capacity to extract the equivalent of more than 12 bath tubs per second.
"The police, fire and rescue service, Environment Agency and the trust would not have allowed people to return home if there was a risk.
"Work to ascertain the cause of the problem with the dam spillway continues and we will report back fully in due course.
"We are also liaising with our engineers to work out the best time in the next few weeks to host tours for residents to see what’s happening on site."
The reassurances come after the Canal and River Trust took over responsibility for the reservoir site around the damaged dam from the emergency services.
Rob Jowitt, who will be managing the repair project for the Canal and River Trust, said: "Moving on from the emergency response, our job is to find out what went wrong and prepare a detailed plan for repairing the damaged dam wall.
"It is a huge job which is likely to take some time.
"As the emergency services leave the site, we want to assure the local community that the reservoir is safe and the dam wall is secure.
"Local people have been amazing during the emergency and we want to keep them to be up to date and part of the project moving forwards.
"As soon as we have a detailed design plan, we will be sharing it with everyone and inviting people on site to special open days to see what is being done."
An initial fish rescue has taken place and a second major phase will take place in mid-October when the weather is cooler and better for the health of the fish.
Coarse fish, such as bream, roach, perch and pike, have been captured in large nets by the trust's fish specialists and then transported to another trust reservoir, Upper Bittell Reservoir, near Birmingham.
Upper Bittell Reservoir, which, like Toddbrook Reservoir, is a Site of Special Scientific Interest, was drained and then refilled after maintenance works two years ago and is in a good position to re-home large numbers of fish.
Paul Breslin, fisheries officer with the Canal and River Trust, said: "We want to save as many fish as we possibly can.
"We have installed aeration pumps to provide the fish with extra oxygen in the water.
"The middle of summer is not an ideal time to move fish as they can get distressed by the heat - but we are working hard to do our very best for the wildlife caught up in this emergency."