Tanja Lingen barely dares to think about the night her two sons went into the family vineyard cellar to salvage what they could of the supplies and equipment as waters from the nearby river Ahr rose to dangerous levels.

“They removed the fermentation airlocks on the oak barrels and replaced them with tight plastic stoppers just in the nick of time,” she says. They even had the presence of mind to film the dramatic scene, by chance capturing the fast disappearing chalk markings on the barrels which meant it was possible to identify what was in them.

“I could only bring myself to watch the film for the first time a few days ago,” she admits. “It made me feel quite queasy.”

Minutes after her boys had plugged the barrels, she recalls, there was a huge bang as an electrical outlet blew. Less than 20 minutes later, the waters from the river crashed into the cellar and house, 250 metres from its banks, reaching as high as the first floor.

Two months after the deluge – worse than anything of its kind ever recorded in Germany – Lingen and other locals are still picking up the pieces.

She has been overwhelmed by the support the family received from voluntary fire brigade and other helpers who assisted with pumping out the cellar and removing the tonnes of sticky sludge from the vineyard – which dates back to 1590 – as well as a guesthouse, in Bad Neuenahr. She’s grateful too for the €23k (£19k) in direct government aid she has received – €15k of which has gone straight into buying a new heating system.

The cellar and tasting room are sauna-like and still smell fusty. She has tasted the wine in the barrels “and I didn’t go down with a tummy bug so that’s a good sign,” she says, her joviality defying the scale of the disaster.

But she is now having to concentrate her efforts on the upcoming grape harvest – due to start in about a week, which is being seen as a hugely significant moment for the region’s 50 vintners, only four of whom did not lose property. They all have been affected by the floods and are struggling to get back on their feet.

An estimated €50m worth of wine has been lost, along with 10% to 15% of 560 hectares of vines, in the Ahr valley – Germany’s largest continuous expanse of red wine production, specialising in Pinot Noir, or what in German is known as Spätburgunder. Many of the destroyed vines were between decades and even hundreds of years old and will take years to replenish.

About 3,000 bottles of the Lingens’ wine which are covered in sludge and unfit for sale are packed in metal crates, labelled with the request “please don’t wash”. They are about to be sent to donors from across Europe who have paid above the odds for them in order to fund a “flood wine” scheme to support stricken vintners. It has so far raised almost €4.5m.

Over the past weeks, the challenge for the vintners has been to ensure that their vines have been kept free of fungal infections, of particular concern due to the high humidity caused by the flood and weeks of torrential rain. Volunteers have been bussed in to help prune them – vintners were preoccupied with cleaning up their vineyards – and more will be on hand to help with the harvest. Help, in the shape of manual labour and donations of machinery, has also been given by vintners from other wine regions across Germany and Europe,

Tanja Lingen’s main concern is her wine press, badly clogged and damaged, which is being repaired in the Mosel valley, and which she is unsure will be back in time for the harvest. “We are calling them every day in the hope it’ll be ready,” she says.

In the meantime the family have been busy washing their 600 litre stainless steel tanks, what Lingen calls a “sisyphean task”, involving removing each of the mud-congested valves and putting them in ultrasonic baths before they are steam cleaned.

Peter Kriechel, head of the Ahrwein trade association whose family has been making wine since at least 1555, feels the strain in his ankles as he stands on the steep slopes of his vineyard – most of which were spared damage – and measures the ripeness of his grapes by crushing a few of them between his fingertips and dropping the juice on the glass prism of a refractor.

It is one of the few pieces of equipment he was able to salvage from the waters, which destroyed his wine press, crusher and de-stemming machines.

Kriechel gazes over the devastated, patchy brown valley below and stresses the determination of the vintners to keep going.

“Wine is our livelihood as well as being a cultural asset,” he says. He also points out the strong symbiotic relationship between wine and the tourism and hospitality industries. Many hotels and restaurants destroyed are unlikely ever to open. In addition there are the hiking trails – including well-trodden, centuries-old wine routes, and scores of bridges and roads which make transportation possible, which may take years to reconstruct.

Kriechel walks through the hollowed out rooms of his own devastated family-run hotel and guesthouse in the village of Marienthal, surveying the damage. The grapes once prettily framing the entrance way are covered in mould and mud.

His eyes well up as he relays how that morning he received the news from an architect and structural engineer that it will have to be torn down. “Some people are asking, ‘is it worth it?’ They suggest that maybe we should just abandon the valley,” he says. “But when your family has been doing this for the best part of 500 years no idea seems more absurd.”