A group of German winemakers from the Mosel valley has called on politicians in the country to halt the planned construction of a highway and road bridge above their Riesling vineyards.

The winemakers have voiced their concerns over a plan to build a 1.7km long, 160m high bridge across the valley, near the towns of Bernkastel-Kues and Traben-Trarbach. The four-lane bridge will carry the B50 road across the Mosel river, with construction set to begin shortly, after the 40-year-old plan had previously hit the buffers due to legal challenges and problems in securing private finance.

The road will emerge from a tunnel through the side of the Ürziger Würzgarten wine mountain, cross the Mosel river via a concrete bridge and continue along the top of the vineyards of Zeltingen-Rachtig, Wehlen, Graach and Bernkastel, with an additional slip road passing close by the village of Erden.

The winemakers are concerned about the long-term impact of the road on water distribution to their vines. Existing forest above the vineyards is set to be removed and the new road embankment will effectively seal off a large swathe of the hilltop. The forest currently forms the water reservoir needed to sustain the vines during the frequent spells of hot weather in the valley.

"The whole project lacks any long-term thinking," said Ernst Loosen of Dr. Loosen wine estate. ""I don't understand why this bridge and motorway is supposed to be built at all. The maximum time saved in any direction of travel can be no more than 30 minutes."

Markus Molitor of Markus Molitor estate in Wehlen, added: "This bridge will destroy the aesthetics of the cultural landscape at the Mosel. The impact on tourism, especially during the lengthy building works will be great.

"The vines will be detrimentally affected by shadow from the bridge, water distribution will be permanently altered; and all this disruption comes not just to anywhere, but precisely to some of the rare 'Grosse Lagen' (Grand cru) vineyards of the Mosel. The main official argument that this road is needed to make the airport Frankfurt Hahn more accessible is highly doubtful: to destroy a cultural heritage environment for a business with no clear future is really a poor trade-off."

No-one was immediately available for comment at the German Embassy in London when contacted by just-drinks today (26 May).