Damage assessment was continuing on Tuesday, days after persistent heavy rain fell at properties across the Midlands and the north of England.
National Trust leaders said climate change meant they should expect more severe weather events and put in measures to protect sites.
Harry Bowell, head of land and nature, said: “We recognise we need to adapt our places to cope with the likelihood of these extreme weather events – and we are already doing that through establishing trees and woodlands, restoring peatlands to hold more water in our landscapes, particularly upland areas – and through our work to reconnect rivers with their floodplains to create new areas of wetland to again help hold the water back in times of heavy and persistent rainfall.
“It is now more important than ever that we play our part to adapt to our changing weather patterns as well as implementing more measures to tackle climate change.
“But we also need more urgent and wide-ranging investment and action to address these issues by governments and leaders across the country.”
The trust runs Cragside in Northumberland, which was the first house to be powered by hydro-electricity.
Rising water levels overwhelmed the Victorian powerhouse and partially submerged the dynamos and turbines.
At the nearby Wallington Estate, beavers were released in the summer and their welfare has been checked after water levels rose significantly on a tributary that runs through their enclosure.
High winds blew a stone ball off one of its garden gates and toppled a sessile oak tree planted around 270 years ago.
On Northumberland beaches, the storm washed up a substance which was potentially harmful to dogs and samples have been sent away.
In the Peak District, the deluge eroded hundreds of metres of footpaths and damaged fences, walls and bridges.
Craig Best, general manager in the Peak District, said his journey home on Friday was frightening, adding: “The chaos and devastation the storm caused to homes, businesses, roads and transport systems in the area is truly shocking.
“It certainly brings it home how vulnerable we are to extreme weather events like this when you see it unfold.
“Let’s not forget though, in good condition the uplands of the Peak District can hold the key to reducing the impact of extreme weather conditions like this.
“They could be our first line of defence.”
There was also damage at Carding Mill Valley and the Long Mynd in Shropshire, where it eroded away banks of the Ashbrooke River.
At Kedleston Hall in Derbyshire, home to an 18th-century pleasure ground and 800-acre wildlife-rich parkland, the storm caused structural damage to a wooden footbridge on the lakeside walk and washed away bench seats.
And at Hardwick Hall in Derbyshire, staff raced to rescue a 300-strong book collection, some dating back to the 16th century, in the Long Gallery as rain leaked through windows.
The National Trust has urged would-be visitors to check with sites online as some areas may be closed during the clean-up operation.