Evolution of River Flows in the Sacramento and San Joaquin Valleys Historical Level of Development Study Technical Memorandum, Final March 2016 Prepared by MWH for the Metropolitan Water District of Southern California …… Table of Contents Executive Summary .................................................................................................................................... 1 Study Approach ......................................................................................................................................... 1 Modeling Tools ......................................................................................................................................... 2 Model Validation ....................................................................................................................................... 3 Model Results ............................................................................................................................................ 3 Climate Change ......................................................................................................................................... 9 Conclusions ............................................................................................................................................... 9 Chapter 1 Purpose and Scope of Work .......................................................................................... 1-1 Study Approach ...................................................................................................................................... 1-1 Organization of Technical Memorandum ............................................................................................... 1-2 Chapter 2 Historical Timeline ........................................................................................................ 2-1 Land Use ................................................................................................................................................. 2-1 Evapotranspiration .................................................................................................................................. 2-5 Stream Diversions .................................................................................................................................. 2-7 Groundwater ........................................................................................................................................... 2-9 Flood Control ........................................................................................................................................ 2-12 Sacramento Valley ...................................................................................................................... 2-12 San Joaquin Valley ..................................................................................................................... 2-13 Basin Imports and Exports ................................................................................................................... 2-16 Sacramento Valley ...................................................................................................................... 2-16 North San Joaquin Valley ........................................................................................................... 2-17 CVP Imports and Exports ........................................................................................................... 2-17 SWP Imports and Exports ........................................................................................................... 2-22 Other Basin Exports .................................................................................................................... 2-24 Delta Inflows ........................................................................................................................................ 2-26 Net Delta Outflow ................................................................................................................................ 2-26 Regulatory Environment....................................................................................................................... 2-29 Water Right Decision 1485 ......................................................................................................... 2-29 Central Valley Improvement Act ................................................................................................ 2-29 Endangered Species Act Listings ................................................................................................ 2-30 Bay-Delta Accord ....................................................................................................................... 2-30 Monterey Agreement .................................................................................................................. 2-31 Water Right Decision 1641 ......................................................................................................... 2-31 CALFED Record of Decision ..................................................................................................... 2-31 Operations Criteria and Plan and Biological Opinions ............................................................... 2-31 Fixed Level of Development Scenarios ................................................................................................ 2-32 1900 Level of Development ........................................................................................................ 2-32 1920 Level of Development ........................................................................................................ 2-32 1940 Level of Development ........................................................................................................ 2-32 1960 Level of Development ........................................................................................................ 2-32 1980 Level of Development ........................................................................................................ 2-33 2000 Level of Development ........................................................................................................ 2-33 2010 Level of Development ........................................................................................................ 2-33 Chapter 3 Modeling Tools and Data .............................................................................................. 3-1 Model Selection ...................................................................................................................................... 3-1 C2VSim ........................................................................................................................................ 3-1 CalSim II ....................................................................................................................................... 3-2 i – March 2016 Historical Level of Development Study Spreadsheet Models ...................................................................................................................... 3-3 Consumptive Use Model............................................................................................................... 3-3 Information Flow between Models ......................................................................................................... 3-3 Data Sources ........................................................................................................................................... 3-4 Inflows .......................................................................................................................................... 3-4 Land Use ....................................................................................................................................... 3-4 Climate Data ................................................................................................................................. 3-4 Stream Diversions ......................................................................................................................... 3-4 Gage Data ..................................................................................................................................... 3-4 Chapter 4 C2VSim Model ............................................................................................................... 4-1 Revisions to Historical C2VSim Simulation .......................................................................................... 4-1 Stream Network ............................................................................................................................ 4-1 Bias Correction ............................................................................................................................. 4-1 Sacramento-San Joaquin Delta ................................................................................................... 4-12 Input Files for Fixed Level of Development Simulation ...................................................................... 4-17 Land Use Category for Fixed Level of Development ................................................................. 4-17 Crop Acreage for Fixed Level of Development .......................................................................... 4-17 Urban Demand for Fixed Level of Development ....................................................................... 4-18 Initial Conditions for Fixed Level