ECUEIL, France (Reuters) - Champagne makers will escape the harsh weather damage hitting other French wines this year thanks to an old tradition that allows them to blend new bubbly with reserves saved from past years.
The 2016 champagne harvest has been hammered by a combination of frost, rains and drought that is set to take output to its lowest for more than 30 years, down around 30 percent from 2015, producers group CIVC told Reuters.
Yet makers actually plan to slightly raise the number of bottles produced to meet an expected increase in global demand for the premium sparkling wine in the coming three years, they said.
In the vineyards of Champagne, producer Nicolas Maillart's harvest was well under way this week with a team of seasonal pickers -- mostly from Spain and Portugal -- racing down the rows of vines snipping off bunches of grapes, some showing severe damage.
The crop experienced severe frosts in the spring, followed by heavy rainfall that led to severe attacks of mildew fungus. Then a heatwave in late August and early September scorched some of the remaining grapes, Maillart said.
"I have never known a year like this, and there has never been as much rain in Champagne in living memory," he said.
But the Champagne region, situated around 150 km (90 miles) northeast of Paris, has a long-standing system in place to cope with capricious weather. Wine makers are allowed to mix output from the last harvest with the best quality wines kept in reserve from prior vintages.
"This means that when the harvest is bad we can even improve quality," Richard Desvignes, producer of champagne Lacourte-Godbillon, said as he showed off large metal drums of vintage reserves. "We are extremely lucky."
Reserves, which can amount to 40 percent of a champagne bottle, are used both for risk management and to maintain the style and character of the wine from year to year.
"The impact of this year's poor harvest will be less negative than if we had not put quality reserves in place in the early '90s," Thierry Gasco, cellar master at Pommery, said during a tour of a section of his 18 km of cellars, carved out of the chalky soil of Reims.
The Champagne region produces about 300 million bottles a year and has more than 1 billion in stock.
"Champagne is a blended wine. We blend years, we blend grape varieties, we blend origins, villages, in champagne, so we are able to achieve resilience in champagne production in spite of hard years," CIVC head Vincent Perrin said.
Further south, in France's famous still-wine regions such as Burgundy and Val-de-Loire, output is expected to fall by 21 and 35 percent respectively, according to farm ministry data.
Producers there will not have Champagne's wiggle room if they want to carry the regional label.
Mixing vintages is strictly forbidden in other famous producing regions, which means the sharp fall in output will directly cut the number of bottles produced.
Additional reporting by John Cotton; Editing by Mark Trevelyan