Root Zone Water Budget • Independently estimate:
• Precipitation (PR) • Evapotranspiration (ET) • Runoff (RO) • Percolation (DP) • Change in Storage (dS)
• Solve for Applied Water (AW) AW = ET + RO + DP + dS – PR
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Butte Valley Water Budget Development
NDVI for Crop Coefficient (Kc)
Reference ET (ETo) Daily ET (ETo x Kc)
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Oregon State University PRISM
AW – Applied Water DP – Deep Percolation
PR – Precipitation RO – Runoff
ET – Evapotranspiration
From Precipitation: NRCS Curve Number (CN) method From Irrigation: Estimated as % of Applied Water
Estimated Daily Based On Soil Type, Precipitation, and Applied Water
Estimated Daily, Generally Negligible on Annual Basis
Closure Term
Butte Valley Water Budget Development
Water Budget Analysis Area
• Majority of Butte Valley Watershed • Watershed area: 388,000 acres • Groundwater basin area: 80,000 acres
• Divided into over 14,000 Polygons • Alfalfa • Grain and Hay • Pastures • Misc. Truck • Strawberries • Idle • Wetlands • Native Vegetation • Developed Areas • Water Bodies
• Land Use Classification • DWR (2000, 2010, 2014)
3 Butte Valley Water Budget Development
Water Budget Analysis Area
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• Entire Butte Valley Watershed
• Watershed area: 388,000 acres
• Groundwater basin area:
80,000 acres
• Divided into over 14,000 Polygons
• Land Use Classification
• DWR (2000, 2010, 2014)
Butte Valley Water Budget Development
• Annual Inflows = Annual Outflows
• Minimal change in root zone storage
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Water Budget Summary by Land Use
Grain and Hay (2010, 2014) Pasture (2009 – 2018)
Alfalfa (2010, 2014)
Butte Valley Water Budget Development
• Annual Inflows = Annual Outflows
• Minimal change in root zone storage
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Water Budget Summary by Land Use
Wetlands (2009 – 2018) Native (2009 – 2018)
Butte Valley Water Budget Development
Strawberries (2010, 2014)
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Groundwater Basin Land Surface Water Budget (2009 – 2018)
Butte Valley Water Budget Development
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Groundwater Basin Land Surface Annual Water Budget (2009 – 2018)
*Note: Positive numbers represent inflows and negative numbers represent outflows.
WET YEAR DRY YEAR
Butte Valley Water Budget Development
Butte Valley Water Budget Development 9
Land Surface Water Budget: Precipitation
• Wet Year: 2011
Butte Valley Water Budget Development 10
Land Surface Water Budget: Precipitation
• Dry Year: 2014
Butte Valley Water Budget Development 11
Land Surface Water Budget: Precipitation
• Wet Year – Dry Year
Butte Valley Water Budget Development 12
Land Surface Water Budget:
Evapotranspiration • Wet Year: 2011
Butte Valley Water Budget Development 13
Land Surface Water Budget:
Evapotranspiration • Dry Year: 2014
Butte Valley Water Budget Development 14
Land Surface Water Budget:
Evapotranspiration • Wet Year – Dry Year
Butte Valley Water Budget Development 15
Land Surface Water Budget:
Applied Water • Wet Year: 2011
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Land Surface Water Budget:
Applied Water • Dry Year: 2014
Butte Valley Water Budget Development 17
Land Surface Water Budget:
Applied Water • Wet Year – Dry Year
Next Steps
• Refine Based on Local Knowledge • Integrate with IDC Model • Integrate with Groundwater/Surface Water
Model • Others?
18 Butte Valley Water Budget Development