Drought raises irrigation question in Barolo

For decades irrigation has been banned in many European wine regions, now with the perception of increasing droughts some regions are questioning this.

Barolo’s Oscar Arrivabene, winemaker and director of Domenico Clerico, told Harpers that the legal prohibition on irrigation was potentially at odds with the realities of a warming climate.

The Bordeaux appellations of Pessac-Léognan, Pomerol and Saint-Emilion have been granted permission to irrigate their vines this year after heatwaves and low rainfall across the region threaten the vines with hydric stress. Normally, irrigation is forbidden in the region although recent modifications to the winegrowers' code – the Cahier des Charges – have allowed it under certain conditions.

With many wine regions themselves short of water, irrigation will require the building of dams to capture water run off, or the installation of wells to access underwater reservoirs. But many producers prefer dry farming as it is known in South Africa. It forces the vines roots to go deeper to access reliable water, reducing the need for irrigation.

Some regions also grow on soils that naturally store water, chalk for example has high water holding capacity, in dry years, vines on chalk typically fare much better than say those grown on sand or gravel. For example in Bordeaux, the left bank vines grown on free draining gravel often suffer in a drought, compared to the vines grown on chalk in St-Émilion on the right bank, but in a wet year the gravel provides drainage.