Data component Source or options Notes Crop ET and Regional ET: - ETAW Option 1: ETo and Kc Option 2: aggregate from more detailed ETo and Kc Option 3: processed satellite imagery Applied Water To be calculated from ETAW and seasonal CWC §531.10 reporting as it becomes efficiencies. [Surface water data from water available may suppliers]. GW use is unmeasured or not reported. Private water rights diversions from SWRCB Improved ways to estimate use are Groundwater measured or estimated, when available needed. Agronomic Options: reported by suppliers; estimated by DWR DWR will develop and recommend Uses procedures. Environmental Reported by water suppliers. Limited studies and DWR will develop and recommend Uses estimates available procedures (to work with suppliers, California Department of Fish and Game and U.S. Fish and Wildlife Service, CARCD, and other groups to develop estimation procedure). Recoverable Reported from water suppliers DWR may develop and recommend procedures Acronyms: ET- evapotranspiration, ETAW = evapotranspiration of applied water, ETo reference evapotranspiration, Kc crop – – coefficient, SWRCB State Water Resources Control Board, CARCD California Association of Resource Conservation – – Districts
Data component Source or options Notes Crop ET and ETAW Regional ET: Option 1: ETo and Kc Option 2: aggregate from more detailed ETo and Kc Option 3: processed satellite imagery - Applied Water To be calculated from ETAW and seasonal efficiencies. [Surface water data from water suppliers]. Private water rights diversions from SWRCB Groundwater measured or estimated, when available CWC §531.10 reporting as it becomes available may GW use is unmeasured or not reported. Improved ways to estimate use are needed. Agronomic Uses Options: reported by suppliers; estimated by DWR DWR will develop and recommend procedures. Environmental Uses Reported by water suppliers. Limited studies and estimates available DWR will develop and recommend procedures (to work with suppliers, California Department of Fish and Game and U.S. Fish and Wildlife Service, CARCD, and other groups to develop estimation procedure). Recoverable Reported from water suppliers DWR may develop and recommend procedures Acronyms: ET- evapotranspiration, ETAW = evapotranspiration of applied water, ETo – reference evapotranspiration, Kc – crop coefficient, SWRCB – State Water Resources Control Board, CARCD – California Association of Resource Conservation Districts
Draft%20Methodology%20for%20Quantifying%20Efficiency%20of%20Ag%20Water%20Use.docx