Just north of Knightsen, a rural enclave east of Brentwood, you’ll find Corteza Vineyards. On this 27-acre piece of land, Art Corteza grows a variety of winegrapes. Although not apparent just by looking, Art’s vineyard is one of the more dynamic vineyards in the county. Art has been introducing new varietals of winegrapes such as Grenache Blanc and Carignan, uncommon in a region known for Old Vine Zinfandel. Recently, however, winegrape growers in Contra Costa County have experienced a reduction in demand for Zinfandel grapes. Thus, Art’s crop diversity has set him up well in the wine market.

As a newer grower in the county, Art has plenty of challenges in establishing his vineyard. One major challenge is irrigation. Originally, Art’s land was 44-acres, but it was later sectioned off to just 27-acres. When this happened, the irrigation was cut and capped, leaving an unknown amount of intact irrigation infrastructure. While the underground pipes and dripline were still intact, a well was needed to create a new water source to irrigate. A few years later, Art learned about Contra Costa Resource Conservation District’s (CCRCD) technical assistance in irrigation and reached out to me. 

Working with Art, I surveyed the vineyard’s irrigation infrastructure. The California Department of Food and Agriculture’s Technical Assistance Program (TAP) promotes irrigation efficiency with the goal of increased water conservation for farmers. Through this program, I performed a pump test to determine the potential total output of Art’s irrigation system and I assessed sections of reduced water output through a Distribution Uniformity (DU) test. The tests determined that the ends of the irrigation rows were getting noticeably less water, so I helped Art reduce the number of rows. Now, more water will reach the ends of the rows, leading to a more consistent grape yield and healthier vines. 

Art hopes to expand Corteza Vineyards by expanding the estate label of his wine. Art is also planning to work with other local growers and winemakers to improve the namesake of Contra Costa County’s wines and create resilience for Contra Costa winegrapes. I am glad to continue to be of service to Art as he works to achieve these goals.