Introduction of Version 2.0b• Significant changes to sediment model

– Box volumes are no longer static.

– Net sedimentation is constrained by box geometry.

– Tributary loads do not include bed loads, only suspended fraction.

– Tributary loads distributed representatively between Bay segments

– Calibrated to net sedimentation for 4 South Bay subregions reported by Jaffe et al.

– Improved boundary conditions at Delta and Lower South Bay. (improved mass conservation)

Introduction of Version 2.0b

• Implications for PCB model:– Improved mass conservation (99.98% daily

conservation)– Improved accounting of sediment-water

exchange.– Constrained erosion/deposition improves

forecast.

Future Plans (v2.0)

• Address comments from v1.0 draft report and incorporate changes into v2.0 (in progress)

• Calibration and Validation– Sediment sampling to improve estimates of PCB inventory and

historic loads

– Tracer experiments to quantify flushing, compare with obs.

• Uncertainty and Sensitivity Analysis – with TetraTech– Monte Carlo type UA

– More rigorous SA

• v2.0 draft and final reports – (Draft = September 2005)