Lewis-Clark Valley is a winegrowing region and designated AVA that covers land in both Idaho and Washington. It was awarded its AVA status in 2016 and at its establishment it shifted the border of the neighboring Columbia Valley AVA. Lewis-Clark Valley is the third appellation to be officially recognized in Idaho.
©Lewis-Clark Valley Wine Alliance
The AVA covers 124,000 hectares (306,500 acres), with only 33ha (82 acres) under vine at its inception, though there are plans already for a further 20ha of vineyards. The valley encompasses the area around the Washington city of Clarkston and the neighboring city, Lewiston, in Idaho. Both are situated at the confluence of the Snake and Clearwater Rivers.
The elevations are lower than the surrounding regions which allows for warmer temperatures and more growing days, with the highest areas of the appellation are all shy of 2000 feet above sea level. Higher elevations in the area are susceptible to temperatures too cold for reliable ripening of grapes and creates the risk of winter frosts cold enough to kill vines. Grapes grown in the region include the vinifera varieties Cabernet Sauvignon, Cabernet Franc, Merlot, Chardonnay and the common Rhône varieties that are popular in the Columbia Valley such as Syrah and Viogner. The scale of wine production is small enough that wineries are still experimenting with what varieties will be the most successful.
A little more than 70 percent of the Lewis-Clark Valley AVA is in Idaho, while the rest extends into Washington and what had been the far eastern area of the Columbia Valley AVA. Because the Alcohol and Tobacco Tax and Trade Bureau has strict rules limiting overlapping AVAs, the Columbia Valley's border was shifted west. Producers on the Washington side of the border lost the Columbia Valley designation in a decision that was opposed by some affected producers for fear that the lesser known Lewis-Clark Valley designation would inhibit sales. The decision was only made after petitions and local growers successfully demonstrated a difference in climate and soil between the overlapping portions of the AVA on the Washington-side and the more westerly parts of the Columbia Valley. A key point of difference was the influence of the Missoula Floods that caused erosion and great gravel deposits that did not significantly travel east to the contested area. The shift in boundary decreased the Columbia Valley by 23,000ha, a tiny portion of its roughly 4.4 million remaing hectares. Lewis-Clark Valley is further defined by the dominant humus-rich mollisol soils that contrast with the volcanic andisol soils of the surrounding regions.
