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Task 4.4 Sediment Budget and Conceptual Model of Coastal Processes Consultant shall develop a concept-level sediment budget, accounting for the inputs and outputs of sediment at the project site. The sediment budget will synthesize site observations, engineering analyses, and historic records to estimate the scale of identified sediment sources and sinks and pathways of sediment transport in the vicinity of the project site, and a summary of the uncertainties of this estimate. The sediment budget will be informed by estimates of sediment supply from San Lorenzo Creek from several recent reports such as Changing Channels: Regional Information for Developing Multi-benefit Flood Control Channels at the Bay Interface (SFE1 2017). As part of this task, consultant shall develop a conceptual model of coastal processes that relate key drivers to the functional physical responses of the system. Consultant shall use the conceptual model to identify the physical processes that have the greatest role in the system response and functional impacts, and to evaluate how possible interventions or actions could affect the processes and result in improved system functions. The conceptual model will be based on the specific categories: drivers or actions, physical processes, physical response, functional response. The conceptual model will support the interpretation and diagnosis of the system in its existing condition, and to identify potential beneficial interventions or restoration actions. Task 4.4 Deliverables • Memo on the conceptual model and the sediment budget in PDF format. Task 4.4 Schedule • Seven months from start of task Task 4.5 Field-Based Geomorphic Assessment Consultant shall conduct a field-based geomorphic assessment, informed by the outcomes of the background document review, field data collection, local wave study, and conceptual model tasks. The geomorphic assessment shall emphasize observations, measurements, and documentation of existing site conditions, with attention to documenting landforms and biological features indicative of historic and ongoing geomorphic processes, such as: surface and shallow-subsurface sediment composition & grain size distributions; dynamic landforms indicating deposition or erosion; and indicators of tidal inundation and wave runup. Consultant shall collect surface and sub-surface data to characterize the sediments at select locations. This will include sediment samples for assessing the composition and grain size, as well as undisturbed sediment cores to assess shear strength and layering of sediments (or alternatively, in-situ measurements of relative shear strength using a shear torvane). It is understood that the East Bay shores include mudflats that were formed at different periods in geologic time, which results in non- uniform erosion and evolution, and which could influence the expected performance of potential future placements of coarse sediments. Task 4.5 Deliverables • Field-based Geomorphic Assessment Memo in PDF format