Grapes thrive in Washington's Columbia Valley

About 15,000 years ago (relatively last weekend in earth's geology), the vast glacial Lake Missoula, burst through an ice dam that stretched from modern-day Canada to Montana. At maximum speed of 80 miles per hour, the collapse cascaded 500 cubic miles of water across the Pacific Northwest, carrying basalt, sand, silt, blocks of granite and massive volcanic boulders as far as Oregon. The lake re-formed and burst again 40 times over the next 2,000 years, leaving the visual legacies of the Columbia River Gorge - 80 miles long and 4,000 feet deep - and the wine country of Washington's Columbia Valley.

Washington is our country's second largest wine producer and Columbia Valley is its heart. Covering roughly the eastern third of the state, Columbia Valley is a desert plateau. The Cascade Mountains to the west trap coastal rain, allowing only 8 inches of annual rainfall. Even the hardiest of plants - the grape vine - wouldn't survive this frozen desert if it weren't for the warmth provided by the massive Columbia River. The river provides water too, pumped through an irrigation system established in 1903, which transformed the desert into fertile farmland.

Established in 1984 (relatively last weekend in wine's timeline), the Columbia Valley AVA (American Viticultural Area), is home to about 400 wineries. With a controllable water supply, a variety of soils deposited from the Missoula flood and extended sunshine - about two more hours daily than California - vineyards yield a wide range of grapes (Cabernet, Syrah, Chardonnay, Sauvignon Blanc ...), and complex wines characterized by concentrated flavors balanced by vibrant acidity.

In addition to Milbrandt, look for widely distributed labels such as Chateau Ste. Michelle and Columbia Winery, and boutique brands De Lille Cellars and Betz Family Winery.

• Advanced Sommelier and Certified Wine Educator Mary Ross writes Good Wine twice a month. Write her at food@dailyherald.com.