Figure 1: Conceptual Model for Benefits to Native Fishes (Delta Habitats Group 2002) Geomorphic Feature. Hydrodynamic Character.

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1 Figure 1: Conceptual Model for Benefits to Native Fishes (Delta Habitats Group 2002) Geomorphic Feature Hydrodynamic Character Function Distributary Channels Deep Fast flowing Open water / Oversized Marsh channels Shallow Perennial flooding Sluggish flow SAV Marsh tidal channels Marsh Surface/ Edge Fast flowing Regularly flooded/ flushed Protection from predation Food resources Native Fishes Tidal Marsh with Dendritic Channels Habitat

2 Figure 1A: Comments from AMWG & others on DHG Conceptual Model Other factors to add to the model Landscape features Substrate Adjacent Habitats Seasonal inundation pattern Fluvial processes: Marsh creek Temperature Competition Types of Food resources Access Geomorphic Feature Hydrodynamic Character Function Spawning Predation by waterfowl Water quality Distributary Channels Open water/ Oversized channels Deep Fast flowing Shallow Perennial Flooding, Sluggish flow SAV?? Marsh tidal channels Marsh Surface/ Edge Fast flowing Regularly flooded/flushed Protection from predation Food resources Native Fishes Tidal Marsh with Dendritic Channels Habitat

3 Figure 2: PSNERP Conceptual Model Level 3.0 (ACTION SCENARIO dike breach example) Restoration Action Restored Processes Structural Changes Functional Response Juvenile salmon access to shallow water habitat Scouring (erosion) of tidal channels increased habitat edge, higher channel order system High tidal channel network complexity Increase juvenile salmon residence time Reintroduce full tidal prism, flooding frequency and duration Suspended sediment transport into subsided marsh area Sediment accretion on subsided surface Higher growth and survival in nearshore Potential Constraints Contaminants Nonindigenous species Increased nutrient delivery and transformations increased sediment trapping Recolonization and growth of emergent tidal marsh vegetation enhanced detritusbased food web rate dependent on subsidence Increase production of benthic invertebrates and insects Increase juvenile salmon prey consumption

4 Figure 3A. Chinook salmon growth: habitats, processes and attributes. Marsh plain Riparian Elevation Frequency and magnitude Adult Insects Primary production Channel edge Aquatic Inverts KS Food Access & egress to migration corridor SAV canopy will block Ushaped Channels Especially small and numerous (minimum 30 cm deep at LLW) Temperature Extreme high temperatures are negative KS Growth (Nov 15June 1) SAV densities Reduce access to food

5 Figure 3b. Chinook salmon survival: habitats, processes and attributes Higher marsh plain Marsh structure Channel shape Shading Deep channels >30cm at LLW Permanent SAV Migratory birds (winter) Distance from nest (spring) Further is better Temperature High temperatures increase disease Disease Fish predation Growth (see other model) KS Survival Size Avian predation Channels $1m deep & 2m wide Flying/diving Channel edge or marsh plain 0.5m max Wading Nonbreeding winter birds

6 Figure 4: Levee Breach and Salinity Dynamics Model Salinity Effects In Delta Dissipation of Tidal Energy Local Salinity Trapping Regional Circulation Changes Tidal Phasing in DS Timing of Exchanges Tidal Prism of Site Marsh Plain Elevation Breach Location (on site) Tidal Range Size of Breach

7 Figure 5a: Levee Breach and Salt Trapping Flood Tide: Flow along Dutch Slough and entering Shallow Tract Conditions in Dutch Slough: Currents driven by along slough surface slope Salinity set by advection: lags by 3 hours (highest at end of flood) Flows into Shallows: Timing of flows set by surface slope and frictional resistence Volume of shallows, size of breach Likely to be centered around high/low water

8 Figure 5b: Levee Breach and Salt Trapping Scenario I: DS tides slack at high/low water (Progressive Wave), Exchange flows peak at high water (no delay) Rising MW Slack HW Salinity in channel increases through flood tide High salinity waters move into shallows at end of flood tide. Falling MW Slack LW Channel freshens while shallows remain saline. High salinity waters released back into Dutch Slough. Leads to salinity intrusion

9 Figure 5c: Levee Breach and Salt Trapping Scenario II: DS flows maximum at high/low water (Standing Wave), Exchange flows peak at high water Rising MW (slack) HW (flood) Period of minimum salinity in DS. No exchange. Exchange flows in phase with channel flows. Salinity around mean value. Falling MW (slack) LW (ebb) Period of maximum salinity in DS. No exchange Salinity released from shallows similar to salinity in channel.

10 MeHg in Fish Figure 6: Mercury Methylation Model MeHg in Bay bioaccumulation transport Food chain MeHg in Water transport Channel Design Marsh Plain Elevation wetting/drying Labile Carbon Plant Types* MeHg in Sediments methylation Hg Hg inputs Tidal Range sulfate Temperature Fe/AVS Soil Amendments

11 Figure 7: Simple HydoGeoEco Simulation Model Design Criteria Other TM Funct. Fish, Other Bio CM Other eg historical Ref. sites Geoecomorpic processes Rest. Actions Alts: 1... n: For channels, marsh plain, spatial configuration Evolution Geoecomorph CM: physical, bio, channel process evolution over time Measurable AM: evaluate CMs, refine if nec., Regenerate rest actions. Funct. Response Bio, phys, channel CMs predict response to evolution Measurable