The proposed Petaluma Gap AVA

The Tax and Trade Bureau (TTB), the government agency responsible for approving new AVAs, opened the Petaluma Gap AVA petition for public comment on October 27. This approval phase will last 60 days. People who wish to voice their support, or concerns, should first review all documents related to the Petaluma Gap AVA application here. Then, you can use this online form to submit your comments on Petaluma Gap AVA.

The Petaluma Gap AVA is located in Sonoma and Marin Counties in California. It’s proposed borders lie largely within the North Coast AVA. The petition also calls for expanding the North Coast AVA so that the entirety of the Petaluma Gap AVA will be included therein. The petition was initially submitted in February, 2015.

The Petaluma Gap AVA will also partially overlap with the Sonoma Coast AVA. No boundary changes are proposed to the latter AVA. That region is quite large but, unlike the North Coast AVA, is limited solely to Sonoma County.

One of the most viticulturally meaningful aspects of the Petaluma Gap area is wind. The name refers to a break in the coastal range of hills and mountains which run roughly parallel to the coast. This “gap” allows cold, oceanic wind to reach farther inland, cooling vineyards with both air and fog.

Though specific micro-climates may vary, this type of cooling generally allows grapes to retain their acidity longer into the growing season. It can also retard sugar accumulation. This can lead to fresher, lower alcohol wines and/or allow growers to let harvest later for deeper color, softer structure and more developed fruit flavors.

Only a portion of the Sonoma Coast AVA is cooled in this way. Sites within the proposed Petaluma Gap AVA routinely experience winds in excess of eight miles an hour. That’s rare in places that are nearby but not affected by the gap. It’s quite common for Petaluma Gap vineyards to have winds that are ten miles an hour faster than these other sites.

The new AVA will include about 4,000 total acres. At the time of application, that included nine wineries and 80 vineyards.

For more information on the proposal, including maps, lists of wineries and growers and related tasting events, visit the Petaluma Gap Winegrowers’ Alliance website.

Copyright Fred Swan 2016. Image courtesy of Petaluma Gap Winegrowers Alliance. All rights reserved.