Estimates of water required
Every new vineyard conversion permit application filed in the Annapolis area within the past two years claims that they intend to dry farm their grapes. These new vineyards are planted at the intensive density rate of 1,100 grape plants per acre.
According to several applications submitted by new vineyard developers in Annapolis, every 45 acres of grapes conservatively consumes 1,000,000 gallons of water each season. They claim they will irrigate with 20 gallons of water per vine during a projected four month growing season, even though the application admits that the normal watering season for the area can last five months.
The applicants also say that in other areas of California each individual grapevine would normally be given 5 gallons per week or 100 gallons per plant during a longer five-month growing season. The bulk of this water will be used within the plants or transpire into the air. Just because the water is applied on the ground does not mean it charges the groundwater basins. Using figures presented in the application, this same 45 acres of grapes irrigated to normal standards would consume about 5,000,000 gallons.
There is quite a difference between a projected claim of using one million gallons in Annapolis and the almost five million gallons used at other locations, especially if multiplied by thousands of acres.