Planning & Environmental Compliance HYDRAULIC MODELING UPDATE Yolo Bypass Salmonid Habitat Restoration & Fish Passage Planning & Environmental Compliance HYDRAULIC MODELING UPDATE November 19, 2013 Sacramento, CA

Hydraulic Modeling Goals Identify Inundation Footprint Inundation Frequency Last Day of Inundation Flow Characteristics Depth Velocities WSEL Analyze a Large Period of Time for Several Alternatives

Past Yolo Bypass Habitat Modeling 1-D Steady-State of Habitat Flows at Fremont Weir 2-D Steady-State of Habitat Flows at Fremont Weir 2-D Steady-State of Habitat Flows at Fremont Weir & Yolo Bypass Tributary Flows

Past Yolo Bypass Habitat Modeling 1-D Steady-State of Habitat Flows at Fremont Weir Habitat flows introduced at a node; no connection w/ Sacramento River No other flows were incorporated into the model A single flow rate was modeled Flow was calculated in one direction only; not good for out of bank flows Fremont Weir KLRC (not included) Flow Introduced at Node

Past Yolo Bypass Habitat Modeling 1-D Steady-State of Habitat Flows at Fremont Weir Habitat flows introduced at a node; no connection w/ Sacramento River No other flows were incorporated into the model A single flow rate was modeled Flow was calculated in one direction only; not good for out of bank flows Time Flow Steady State Flow

Past Yolo Bypass Habitat Modeling Fremont Weir Flow Introduced at Node Flow Calculated in 1 Direction only Example Cross Sections KLRC (not included) 1-D Steady-State of Habitat Flows at Fremont Weir Habitat flows introduced at a node; no connection w/ Sacramento River No other flows were incorporated into the model A single flow rate was modeled Flow was calculated in one direction only; not good for out of bank flows

Past Yolo Bypass Habitat Modeling Fremont Weir Flow Introduced at Node Flow Calculated in 2 Directions KLRC (not included) 2-D Steady-State of Habitat Flows at Fremont Weir Habitat flows introduced at a node; no connection w/ Sacramento River No other flows were incorporated into the model A single flow rate was modeled Flow was calculated in two directions

Past Yolo Bypass Habitat Modeling Fremont Weir Knights Landing Ridge Cut Cache Creek Willow Slough Flow Introduced at Node KLRC Flow Node Putah Creek Flow Node Putah Creek Flow Calculated in 2 Directions 2-D Steady-State of Habitat Flows at Fremont Weir & Yolo Bypass Tributary Flows Habitat flows introduced at a node; no connection w/ Sacramento River Flow was calculated in two directions KLRC, Cache Creek, Willow Slough, & Putah Creek flow included Single flow rates were modeled

Past Yolo Bypass Habitat Modeling 2-D Steady-State of Habitat Flows at Fremont Weir & Yolo Bypass Tributary Flows Habitat flows introduced at a node; no connection w/ Sacramento River Flow was calculated in two directions KLRC, Cache Creek, Willow Slough, & Putah Creek flow included Single flow rates were modeled Time Flow Steady State Flow Habitat Flow Cache Crk. KLRC Putah Crk. Willow Slough Average Flows Expected When Habitat Flows were Available Between Dec. 1st & Mar 31st, from 1968-1998

Yolo County/NHC Review (2012) of The Last Yolo Bypass Habitat Modeling Model availability Topography and bathymetry Boundary conditions Computation assumptions Calibration and validation

Yolo County/NHC Review Model Selection / Availability Consider use of public domain models A survey conducted at a HMAT meeting on 2/4/13 showed that modelers were less interested in public domain models TUFLOW Classic Model Selection Vetted through HMAT Growing use within DWR GIS integration Numerical stability Robust wetting and drying 1D/2D linking

Yolo County/NHC Review Topography and Bathymetry Inaccurate data (e.g., obscured LiDAR) should be corrected New modeling effort is using CVFED LiDAR data or LiDAR data that was QA/Q’d through their exhaustive review process

Yolo County/NHC Review Topography and Bathymetry Additional data should be collected (e.g., missing creek detail and drain culverts) New Data Sacramento Valley CVFED LiDAR Steamboat Slough Lower Putah Creek Sacramento Slough Knights Landing Ridge Cut Miner Slough Willow Slough CVFED Creek & Rivers single beam Tule Pond/Canal & Ag crossings Yolo Bypass Features Sac. River Major ag roads, berms, ag structures, & irrigation ditches Deep Water Ship Channel not included: Field rice checks & culverts Prospect Island Cache Slough Sutter Slough

Yolo County/NHC Review Topography and Bathymetry Inaccurate data (e.g., obscured LiDAR) should be corrected Quality Control Data sources Vendor QC Meets published accuracy standards Internal QC before and after integration Obscured data errors Ponding, aquatic vegetation, dense riparian Techniques to reduce errors Manipulate or screen data Selective 1D/2D linking Sensitivity Analysis

Yolo County/NHC Review Boundary Conditions The reliability of inflows should be verified (e.g., Westside tributaries) Hydraulic structures should be added (e.g., Los Rios Check Dam) Hydraulic roughness should be verified Waterfowl assumptions should be included (i.e., managed ponding)

Model Domain and Boundary Conditions NEW OLD

Model Boundary Conditions OLD NEW Time Flow Steady State Flow Steady State Flow Daily Flows Modeled, So Flow Varies With Time. Water Years 1997 – 2012 Will Be Modeled. Flow Habitat Flow Cache Crk. KLRC Putah Crk. Willow Slough Time Average Flows Expected When Habitat Flows were Available Between Dec. 1st & Mar 31st, from 1968-1998

Westside Tributaries Boundary Conditions Source Data type Ridge Cut Slough inflow DWR’s Water Data Library (A02930) and this study1 Gauged flow and estimated flow Cache Creek Settling Basin inflow This study Estimated flow from gauge data Willow Slough Bypass inflow Yolo Bypass Management Strategy Estimated flow Putah Creek inflow

Knights Landing Ridge Cut

Cache Creek

Hydraulic Structures Affecting Shallow Flooding Wallace Weir Three agricultural crossing on Tule Canal Swanston Ranch check dam Willow Slough access and check dam Los Rios Check Dam Lisbon Weir

Hydraulic Structures Affecting Large Floods Fremont Weir Sacramento Northern railroad Interstate 5 causeway Sacramento Weir gate operations Southern Pacific railroad Interstate 80 causeway and embankments Delta Cross Channel operations Multiple bridges on the Sacramento and American Various restricted height levees

Hydraulic Roughness CV Riparian Mapping Project

Yolo County/NHC Review Computational Assumptions Model cell size should be refined TUFLOW End user can easily change Balance resolution, accuracy, and runtimes Currently using 100 to 200 ft cells Field scale features GIS integration 3D breaklines (e.g., berms and ditches) Sensitivity testing

Yolo County/NHC Review Computational Assumptions Wetting and drying should be validated TUFLOW Wetting & Drying Very robust Start fully dry Isolated pools Does not lead to instabilities Default thresholds 0.007 ft cell ctrs 0.003 ft cell sides

Yolo County/NHC Review Calibration and Validation Detailed model calibration and validation should be performed Calibration and Validations 1997 Flood (V) Yolo Bypass Corps / gauge flows HWMs 2006 Flood (C) Sacramento River Sutter Bypass Gauge flows 2010 Low Flow (C) Tule Canal and Toe Drain capacity ADCP and HWMs 2011 Recession (C) Yolo Bypass Air photo sequence Gauge flows Limited HWMs

Questions?

Time Period Selection

Linking 1D and 2D Domains From TUFLOW Manual

Test Model Test Model Created to… Rough Model Determine Feasibility Estimate Grid Resolution Rough Idea on Runtimes Rough Model Older Lidar Some modifications made to ensure flowpaths in canals and under bridges

Resolution Comparison

Courant Criteria Timestep is Courant Limited Almost always < 10 Often around 5 or less Cutting cell size in half increases runtimes 8 times! 𝐶 𝑟 = ∆𝑡 2𝑔𝐻 ∆𝑥 Where: ∆𝑡=𝑡𝑖𝑚𝑒𝑠𝑡𝑒𝑝, 𝑠 ∆𝑥=𝑐𝑒𝑙𝑙 𝑠𝑖𝑧𝑒, 𝑓𝑡 𝑔=𝑎𝑐𝑐𝑒𝑙𝑙𝑒𝑟𝑎𝑡𝑖𝑜𝑛 𝑑𝑢𝑒 𝑡𝑜 𝑔𝑟𝑎𝑣𝑖𝑡𝑦, 𝑓𝑡 𝑠 2 𝐻=𝑑𝑒𝑝𝑡ℎ 𝑜𝑓 𝑤𝑎𝑡𝑒𝑟, 𝑓𝑡 Cell size Depth Timestep Courant 200 10 60 5.4 100 30 50 12 4.8

Estimated CPU time - 6 month Simulation Test Model Runtimes Grid Resolution Estimated CPU time - 6 month Simulation hours 400 ft 0.73 200 ft 5.8 150 ft 17.1 100 ft 62.6 50 ft 524.2 (22 days) Model Runtimes will vary from above: Domain will be different Runtimes will vary depending upon number of wet cells Easy to switch cell resolution: Initial runs coarse resolution. Final runs fine resolution. Many simulations will be run at the same time (32+)

Ponded Water Model will not drain entirely Small drainage paths may not be well represented Puddles really exist (would evaporate/infiltrate) Puddles in long-term simulations Make it difficult to determine end of inundation period Provide decreased storage during next inundation period Look unrealistic Increase runtimes (wet cells) Infiltration options under review