Feature by Jakob Walter, PE, and Kush Chohan, PE, GE

McMillen Jacobs Associates maintains a diversified portfolio of projects in California. For 20 years we have provided design and consulting services for underground wine facilities and personal event spaces on privately owned sites that have been constructed either by mined or cut-and-cover methods. While these special projects have historically been focused in Napa, Sonoma, and San Luis Obispo Counties, we have recently expanded our services to similar projects in Southern California (Moraga Vineyards) and the Pacific Northwest (Figgins Family Wine Cave).

Within the hills of the wine country in California the large wine production and storage caves have often been excavated by roadheader and drill-and-blast methods, with a final lining provided by means of reinforced shotcrete. Increasingly, however, clients have shown a desire for personal cave structures on residential sites in regions with softer ground and less cover. In satisfying this growing demand, McMillen Jacobs has gained significant experience designing final lining systems that are often reinforced concrete structures that can be built within a temporary excavation. The teams tasked with such projects have managed and performed design for both temporary support of excavation and final cave construction as well as surface drainage and grading layouts. By addressing all these aspects of a residential cave project in-house, McMillen Jacobs can serve clients to a fuller capacity while simplifying the design and permitting process for all stakeholders.

Palmaz Winery Barrel Storage

While the market for cut-and-cover wine caves and event spaces has grown in recent years, McMillen Jacobs continues to design excavated caves on a much larger scale. The firm has been engaged in and continues to be awarded large production wine facility projects such as Palmaz Vineyards Winery Cave, in which all aspects of wine making can operate underground. This provides an environmentally stable condition for wine fermentation and aging as well as a resilient structure safe from seismic and wildfire occurrences.

In addition, wine caves can be less expensive than aboveground warehouses. Even if the initial cost of cave construction is slightly higher than for an aboveground structure, this increased construction cost is offset by eliminating heating, cooling, and humidity-control equipment and monthly bills. No climate control is required in a wine cave, and the year-round constant temperature and humidity are optimum for wine storage. Corks and barrels do not dry out, thus reducing the amount of wine lost to evaporation.

We are enthusiastic about our growing business of design services for large, production-scale winery caves, as well as smaller residential use caves. Please reach out to us if you have any questions or inquiries about a special underground project you or your colleagues are considering.

For more information contact Kush Chohan at Chohan@mcmjac.com.