Dos Rios AVA

Dos Rios AVA occupies a remote corner of northern Mendocino County, roughly 40 miles north of Ukiah and 25 miles east of the Pacific Ocean. The AVA sits at the confluence of the Eel River and the Middle Fork of the Eel River, a setting that inspired its name. Its L-shaped boundary follows steep, terraced slopes with gradients ranging from 30 to 75%, making this one of California's most challenging viticultural landscapes. The surrounding area is known as much for white water rafting as for viticulture.

• Part of the broader North Coast AVA and Mendocino County
• Total area of 15,500 acres, though commercial viticulture covers only 6 acres
• L-shaped AVA boundary defined by steep, terraced river-valley slopes
• Confluence of Eel River and Middle Fork of the Eel River defines the heart of the appellation

Dos Rios experiences a transitional Mediterranean climate that blends maritime and continental influences. Marine breezes channel through the river valleys, moderating summer temperatures and keeping winters relatively mild. This interplay of ocean air and inland conditions creates a frost-free growing season that varies considerably, from 125 to as many as 250 days annually, giving growers meaningful flexibility depending on site and vintage.

• Transitional Mediterranean climate with both maritime and continental characteristics
• Marine breezes moderate summer heat and soften winter cold
• Frost-free season ranges from 125 to 250 days, a wide variation reflecting terrain diversity
• Cooler summers and warmer winters compared to purely continental inland sites

The soils of Dos Rios are well-drained to excessively well-drained loams, sandy loams, and gravelly loams, ranging from deep to very deep profiles. They are weathered from sandstone, siltstone, schist, and greywacke, and are rich in mineral nutrients. Despite this mineral richness, the soils are very rocky, with poor fertility and limited water retention. These challenging conditions naturally restrict vine vigor and encourage the deep rooting associated with concentrated, premium-quality fruit.

• Loam, sandy loam, and gravelly loam soils derived from sandstone, siltstone, schist, and greywacke
• Well-drained to excessively well-drained; limited water retention stresses vines beneficially
• Mineral-rich but low in fertility, promoting low yields and concentrated fruit
• Very rocky texture throughout, consistent with the steep terraced slope environment

Dos Rios is dedicated entirely to red wine production. The approved varieties reflect both Bordeaux and Rhone influences, with Cabernet Sauvignon, Cabernet Franc, Merlot, and Petit Verdot representing the Bordeaux family, while Syrah broadens the palette. Zinfandel and the rare Italian-origin Charbono round out the plantings. With only 6 acres under commercial cultivation and a single operating winery, Vin de Tevis, the AVA operates at extremely low volumes with a clear focus on premium production.

• Approved red varieties: Cabernet Sauvignon, Cabernet Franc, Merlot, Petit Verdot, Syrah, Zinfandel, and Charbono
• Exclusively a red wine AVA; no white varieties are currently cultivated
• Vin de Tevis is the sole commercial producer operating within AVA boundaries
• Low-volume, premium production model driven by the scarcity of viable vineyard land

The Dos Rios AVA was established on October 13, 2005, by the Alcohol and Tobacco Tax and Trade Bureau. The petition was submitted by Ralph Jens Carter of Sonoma, California. The name honors the defining geographic feature of the area, the Spanish phrase 'Dos Rios' meaning 'two rivers,' a reference to the confluence of the Eel River and the Middle Fork of the Eel River. Despite the AVA's large total acreage, commercial vineyards remain limited to just 6 acres, with the research data noting potential for additional plantings in the future.

• Established October 13, 2005 by the TTB
• Petitioned by Ralph Jens Carter of Sonoma, California
• Name translates from Spanish as 'two rivers,' referencing the Eel River confluence
• Only 6 acres of commercial vineyards as of 2023, within a 15,500-acre AVA boundary