Well Water Use

California AgQuest Consulting Well Water Use Calculator

The amount of water used during a growing season for a grape vineyard can be estimated based on research work by the University of California. This research work is used as the basis of the "well-watered" calculations.
Background Discussion About This Calculator

Enter your Starting Date
Select your Weather Station
Trellis System
Cross Arm Width (in)
Row Spacing (ft)
Vine Spacing (ft)


	Crop Coeff, Kc	% Shaded Area	*Well Watered Use For Week
			Inches/wk	Gallons/vine/wk

			*These amounts must be adjusted for RDI and irrigation distribution uniformity.

Notes for Applying Well-Water Use Results: 1. The calculation is based on "normal" climate conditions for the specified weather station and "clean" cultivation (i.e. no actively growing cover crop). 2. The calculated well water use for the week should be multiplied by the percentage of well-water use intended for a specific vineyard. The weekly water use will be decreased by the degree of RDI. If the degree of RDI is intended to be 70%, then the weekly water use should be multiplied by 0.70. 3. The calculated well-water use for the week is for an irrigation system that distributes water with a 100% uniformity. Therefore, the weekly water use should be increased by the estimated Distribution Uniformity (DU) of a specific system. This is done by dividing the calculated weekly use by the DU. If an irrigation system has a DU of 80%, then the weekly water use should be divided by 0.8. 4. A beginning date for calculations is limited to May 1 or later since the equations developed through research tend to over predict water use very early in the growing season Disclaimer: The calculation of grapevine well-water use is intended as a guideline for growers. California AgQuest Consulting assumes no liability for the application of this information to a specific vineyard situation. Factors that can influence local conditions include the soil chemistry and/or the presence of soil pests. In addition to understanding local conditions for a specific vineyard, the implementation of an irrigation strategy should be supported by monitoring the status of both the soil moisture and vine stress.