Residents of a town evacuated due to fears a nearby reservoir could collapse will be temporarily allowed home to collect essentials as the damaged dam remains at a “critical level”.

Water levels at the Toddbrook Reservoir have been reduced by half a metre but engineers remain “very concerned” about the integrity of the damaged 180-year-old structure, which contains around 1.3 million tonnes of water.

Hundreds of people have been evacuated from the Derbyshire town of Whaley Bridge over fears it could rupture and flood their homes.

Prime Minister Boris Johnson is visiting Whaley Bridge amid the concerns over the dam.

An RAF Chinook and around 150 firefighters using high-volume pumps appear to have partly stabilised the “unprecedented, fast-moving emergency situation” caused by heavy rain.

During a multi-agency press conference, Assistant Chief Constable Kem Mehmet of Derbyshire Police said there was still  “a substantial threat to life” if the dam wall fails.

“We would ask residents to continue to heed police advice and stay away from Whaley Bridge,” he told the press conference on Friday.

Due to concerns raised by residents over pets being left behind, he said officers had made the “difficult” decision to allow people to return to their homes temporarily.

“We will be putting plans in place for residents to return to their home to pick up very vital things they need along with their animal welfare,” he told reporters.

“This is very controlled, I must stress that, because this is still life at risk.”

Summer weather August 2nd 2019
An RAF Chinook helicopter flies over Whaley Bridge (Danny Lawson/PA)

Numbers returning will be restricted to one person per household, he said, and it was “difficult” to say when people would be allowed to return permanently.

Julie Sharman, chief operating officer for the Canal and River Trust, told the press conference the water level needs to be reduced by “several more” metres, with more pumps being installed on Friday evening.

“This is still a very critical situation,” she said.

“Until we are confident we can control that risk, then our position has to be to protect the public safety and limit access because we don’t want to put people at risk.”

The Chinook has been dropping one-ton sandbags on to the damaged area to bolster the structure.

Improving weather and work on the inflows means the amount of water entering the reservoir has also reduced.

WEATHER Rain
(PA Graphics)

Police have closed railway lines in the Whaley Bridge area over the risk of potential flooding.

The Prime Minister said “first responders, engineers and RAF crews are working around the clock to fix the dam” and he has ordered Environment Secretary Theresa Villiers to chair a meeting of the Cobra emergency committee to discuss the situation.

Around 1,000 people were evacuated from the town but most found their own accommodation with family and friends, according to Derbyshire County Council.

Dam repair work
An RAF Chinook helicopter is placing sandbags on the damaged area of the dam wall (Danny Lawson/PA)

Carolyn Whittle, who lives in Meadowfield on the hillside in Whaley Bridge, said: “I’ve lived in Whaley for the best part of 45 years and I’ve never seen water flood over the dam like that, ever, nor thought that we could possibly be at risk in this way.”

The Environment Agency issued a “danger to life” warning covering the River Goyt on Thursday, as the river could “rise rapidly” due to water rushing in from the reservoir.

Meanwhile, clean-up operations are under way across parts of the North West hit by heavy rain, including Poynton in Cheshire – where residents were evacuated on Wednesday night.

The Environment Agency has 10 flood alerts, six flood warnings and one severe flood warning in place across England.

Toddbrook Reservoir
The dam holding back Toddbrook Reservoir towers over the town of Whaley Bridge (Danny Lawson/PA)

Richard Parry, chief executive of the Canal and River Trust, said an annual inspection of the Toddbrook Reservoir by a senior engineer took place last November.

The reservoir is on the north-west edge of the Peak District National Park and was built in 1831, according to experts, although the Environment Agency records it as being built in 1840-41.

According to a 2011 Environment Agency report on national dam incidents, Toddbrook “has a history of leakage”.