Dozens of roads have been closed in Derbyshire, where a major incident was declared in the wake of Storm Christoph.
At one point 40 flood warnings were in place, with the River Derwent's peak reaching Derby in the afternoon.
Some homes and businesses have been flooded in the Bakewell area and the centre of Matlock is impassable.
Resident Bill Storey said water arrived "with such force". "It seemed to surround us really quickly," he added.
The warnings span the county, from the River Trent in Swarkestone to the River Derwent at Chatsworth.
Simon Spencer, deputy leader at Derbyshire County Council, said the major incident was declared because of the potential risk to life.
"We have to make sure we co-ordinate as best we can to mitigate the impact of this flooding," he said.
He said the major incident would bring together organisations such as the police, fire and support agencies to co-ordinate the response.
"With Covid restrictions it is an absolute nightmare for those on the front line, and I pay tribute to all those involved," he said.
Later the council leader, Barry Lewis, announced a £100,000 fund for residents and businesses affected by flooding.
The Derwent at Chatsworth rose to 4.02m (13ft) on Wednesday night but has started to drop.
Flood barriers have been put in place at Hall Leys Park, in Matlock, and the main road through the town has been closed, with water coming out of the drains.
The Derbyshire Dales district was badly affected overnight, with homes in part of Bakewell swamped and the town briefly cut off.
As the water moved south throughout the day, the car park at Elvaston Castle Country Park was closed in the afternoon due to flooding on the estate.
Derbyshire County Council asked people to avoid walking there as the lake had overflowed and many paths were submerged in water.
Meanwhile, in Nottinghamshire, a car had to be towed out of the Rufford Lane ford, prompting a warning from the Environment Agency.
The ford is the site of some of the highest number of flood rescues in England.
At Attenborough Nature Reserve in Nottinghamshire, the flood gates have been closed due to the River Trent's rising water levels, Broxtowe Borough Council said.
The flooding on one residential street in Bakewell was the "worst in more than 40 years", according to resident Mr Storey.
Mr Storey lives on Wye Bank, where council and emergency workers have been trying to protect houses overnight.
He said: "It's heartbreaking. A couple of people have said it has got into their ground floors and it's river water, so it's not clean.
"It was only a trickle during November 2019 but this came through with such force, it seemed to surround us really quickly.
"I'm a flood warden and I keep my eye on it and I could see this was on its way but you can't stop it going through."
The A6 was closed at Matlock and Rowsley and the fire service urged drivers not to risk going through standing water.
The River Derwent in Derby reached its peak of 2.58m (8.46ft) at about 17:00 GMT on Thursday before starting to drop.