Brian Joyce, Stockholm Environment Institute Brian.Joyce@sei-us (530) 220-2111

1. A Climate Driven Model of the Water Resources of The Sacramento and San Joaquin Hydrologic Regions: Model Structure and Data Inputs Brian Joyce, Stockholm Environment Institute Brian.Joyce@sei-us.org (530) 220-2111

2. Supported by California Department of Water Resources • In Collaboration with: • David Yates • National Center for Atmospheric Research • David Groves • RAND Corporation • Andy Draper • Montgomery-Watson-Harza

3. Sacramento/San Joaquin Valley WEAP Model

4. Level of Analysis • Planning Areas (PA’s) • 11 PA’s in Sacramento River Hydrologic Region • 4 “Rim” PA’s • 7 “Valley” PA’s • 10 PA’s in San Joaquin Hydrologic Region • 4 “Rim” PA’s • 6 “Valley” PA’s • Also include 1 “Valley” PA in the Tulare Lake Hydrologic Region

5. Trinity River Pitt River Thomes/Elder Creek Stony Creek Feather River Cache Creek Yuba River Bear River Putah Creek American River Cosumnes River Mokelumne River Stanislaus River Tuolumne River Merced River San Joaquin River Watersheds • Sacramento Hydrologic Region • 4 “Rim” Planning Areas • 15 Watersheds • San Joaquin Hydrologic Region • 4 “Rim” Planning Areas • 11 Watersheds • North Coast Hydrologic Region • 1 “Rim” Detailed Analysis Unit • 1 Watershed

6. 500 m Elevation Bands

7. Two-Bucket Approach

8. Land Use Classification • Hydrology module is applied for each land class within a catchment object • Estimates streamflow, as well as snow accumulation/melt

9. Irrigation and Refuge Demands • Sacramento River Hydrologic Region • 7 “Valley” PA’s • 9 Agricultural Demand Areas • 8 Managed Wetlands • San Joaquin Hydrologic Region • 6 “Valley” PA’s • 9 Agricultural Demand Areas • 2 Managed Wetlands • Tulare Lake Hydrologic Region • 1 “Valley” PA • 1 Agricultural Demand Area • 0 Managed Wetlands

10. Land Use Based Demands

11. Irrigated Areas • Hydrology module estimates irrigation demands for 20 crop types • Input requirements: Crop schedule, Kc, Rooting depth, Soils data • Also, estimates water demand for Outdoor Urban • Input requirements: same as crops

12. Managed Wetlands • Wetlands use same catchment object and hydrology routine as irrigated areas. • Also includes “ponding” and “flow through” requirements

13. Urban Indoor Demands

14. Urban Indoor • Single Family and Multi Family demands estimated as function of water use per household • Industrial and Commercial demands estimated as a function of water use per employee

15. Priority = 17 Preference = 1 Limit = 50% Demand Preference = 1 Limit = 40% Demand Preference = 3 Priority = 15 Limit = 100% Demand System Operations • Reservoir releases and water deliveries “operated” using • Storage Priorities • Storage Buffers • Supply Preferences • Transmission Constraints

16. System Operations • In-Stream Flow Requirements (IFR) are treated as demand objects. Assigned priorities relative to agricultural and urban water demands. • 21 IFR’s in model. Includes AFRP, Delta Outflow, and others

17. System Operations Sacramento-San Joaquin Delta • Water quality considerations: • Use GMOD for Delta salinity standards • Use Kimmerer-Monismith to estimate required net Delta outflow to maintain X2 • Delta exports • Constrained by VAMP, E/I Ratio • Target San Luis filling Sep-Mar

18. Questions Brian Joyce Stockholm Environment Institute Brian.joyce@sei-us.org (530) 220-2111