Snake River Valley is an American Viticultural Area (AVA) in south-western Idaho. Located near the state capital, Boise, it covers five million acres (two million hectares) along the Snake River, and includes more than 90% of Idaho’s vineyards. A diverse range of wines are produced in the valley from grape varieties including Chardonnay, Riesling, Merlot and Syrah.
The AVA’s borders are defined by the ancient (now dry) Lake Idaho and the moderating climate afforded by the Snake River, which wends its way across southern Idaho before turning north to mark the border between the states of Oregon and Idaho, finally joining the larger Columbia River near the Yakima Valley AVA. A small, northern portion of the Snake River Valley AVA crosses into south-eastern Oregon.
Idaho's first vines were planted in the north of the state in the 1860s, but viticulture didn't arrive in the Snake River Valley until the 1970s. The AVA was approved in 2007 (five years after the first application), breathing new life into the state's little-known wine industry. This means that Snake River Valley wineries no longer have to use the misleading generic state appellation, but rather have the credibility of an official viticultural area. The industry here has grown rapidly in the past decade, climbing from 11 wineries within the AVA in 2002 to more than 50 today.
The Snake River Valley is made up of flat, river-basin land with altitudes ranging from 2100ft to 3400ft (640–1036m) above sea level, surrounded by even higher mountains. Although the growing season in the Snake River Valley is considerably shorter than in regions in Washington and Oregon, the intense sunlight and high diurnal temperature variation brought about by the altitude are often sufficient to ripen the grapes. White wines from the region display piercing acidity and minerality, crisp fruit flavors and lower alcohol – all of which are related to the short and extreme growing season. Red wines are more problematic – while often they show balance and harmony, with an Old World elegance, they can also be thin, tannic and lacking in ripe flavors.
The Snake River is vital to the region's overall terroir because it provides not only water for irrigation (necessary in the AVA's dry environment), but also unique mesoclimates. Air currents cooled by the river help, in turn, to cool nearby areas, which is particularly beneficial in this hot climate. In winter, the wind currents work in the opposite way, warming the surrounding areas sufficiently to stop the vines from being killed by the cold. Soils are varied, but are generally free draining, derived from sediments left by the now-dry Lake Idaho. The sandy soils and extreme temperatures mean that the vine-killing phylloxera louse cannot survive here.
Snake River Valley is currently Idaho's only AVA, but two others are being considered by the Alcohol and Tobacco Tax and Trade Bureau (TTB). One of them, Willow Creek Idaho, would be located within the current Snake River Valley AVA boundaries.
