The Geography of Wine

Delivering Location Intelligence to the American Wine Industry

Great wine starts with geography

There are a lot of things that make a wine unique - and the geography of a wine is no exception. Temperature, climate, elevation, and soil type all play a part.

The  Alcohol and Tobacco Tax and Trade Bureau (TTB)  designates grape-growing regions with distinguishable geographic features and boundaries as  AVAs (American Viticultural Area's) .

Sonoma Valley, California in 3D

Understanding American Viticultural Areas

For more than 40 years, American Viticultural Area (AVA) designations have allowed vintners to more accurately describe the origin of their wines and help them build and enhance the reputation and value of the wines they produce. There are 242 established AVAs in the United States, with California having the most at 139, and no two regions are alike. AVAs can vary in size, ranging from a small region on a mountain side to an area spanning multiple states.

Many AVAs highlight special features like volcanic soil or high elevation, which gives their grapes a unique flavor.

Napa Valley, pictured above, is known globally for it's award winning wines.

Napa Valley, pictured above, is known globally for it's award winning wines.

Defining AVAs

The official boundaries for AVAs are detailed in the United States  Code of Federal Regulations  and reviewed, approved, and maintained by  TTB . Laid out in an almost narrative format, the code describes boundaries following various hydrographic features and contour lines.

To join the Umpqua Valley AVA in Oregon, the vineyard has to fall within the boundaries defined above.

In order to ensure all AVAs are consistent, a strict process is in place for petitioning for a new AVA or for expanding an existing one.

Each AVA proposal must include:

  • Proposed AVA name, which directly relates to the proposed location with external evidence to the significance of the name.
  • A USGS map or maps that outline the proposed AVA boundaries and its description.
  • Evidence for why the drawn boundary encompasses a unique region, including climate, soil composition, and/or physical characteristics that the boundary follow, such as elevation contours or rivers.
  • A step by step list of distinguishing features that demarcate the boundary of the proposed AVA, following specific Federal Code of Regulations wording and guidelines.

Some AVAs cover multiple maps and have to be laid out on the ground to see the full extent of their borders.

Traditionally, AVA boundaries were carefully handrawn and edited on paper maps. But recently, TTB has digitized the 242 AVAs using ArcGIS, making the review and approval process easier. What once had to be be done by hand, has become simple clicks on a webmap.

All 242 AVAs are now publicly available through the AVA Map Explorer


Wine Regions vary from Coast to Coast

From Vineyard to Kitchen Counter

AVAs affect everything from the taste to the label.

AVAs help to make wines stand out from their competition. By highlighting the regions and micro-climates in which grapes are grown, certain wines and AVAs can attract loyalty with just a name.

Similar to the TTB's strict requirements in designating an AVA, they also have strict labeling requirements that encompass everything from type of wine to the location the grapes were grown and the percentage of the wine itself.

America's Wine Regions Are Expanding

While other organizations and universities have created partial or complete AVA datasets for their own uses, the TTB polygons and the CFR remain the official source. All 242 AVA can now be explored directly using the  AVA Map Explorer  on TTB's website.

AVAs are constantly changing and evolving. With 17 proposed AVAs in review, which are also visible in the Map Explorer, more wine flavors and varieties could be on the way soon — and that’s something we’ll drink to.

Cheers!

For any questions regarding AVAs, contact:

Karen A. Thornton

AVA Program Manager

TTB Regulations and Rulings Division

Napa Valley, pictured above, is known globally for it's award winning wines.

To join the Umpqua Valley AVA in Oregon, the vineyard has to fall within the boundaries defined above.

Some AVAs cover multiple maps and have to be laid out on the ground to see the full extent of their borders.

All 242 AVAs are now publicly available through the AVA Map Explorer