San Francisco Bay Coastal System

Overview

San Francisco Bay is a heavily urbanized estuary that is impacted by numerous anthropogenic activities, including channel dredging, aggregate mining, delta discharge and sediment load regulation, urban run-off, urban sediment trapping, heavy ship traffic, oil spills, exotic species introduction, and salt pond restoration. The Golden Gate strait is the sole inlet connecting the Bay to the Pacific Ocean, and serves as the conduit for over 2 trillion gallons of water daily in addition to the transport of mud, sand, biogenic material, and pollutants. Despite this physical, biological and chemical connection, prior research has typically treated the Bay and adjacent Ocean as separate entities, compartmentalized by artificial geographic boundaries, such as the Golden Gate Bridge.

However, recent research completed as part of the USGS Project "Coastal Evolution: Process-based, Multi-scale Modeling" has demonstrated the dynamic nature of processes at the mouth of San Francisco Bay, but more critically the important connection between San Francisco Bay physical processes and the adjacent coastal environment. This new project, the San Francisco Bay Coastal System, will treat the region as a single physical entity that is impacted throughout by physical processes and anthropogenic activities from the delta to the shelf edge.

The primary goal is to identify the physical processes and anthropogenic influences that have resulted in significant morphological changes to the San Francisco Bay Coastal System. This, in turn, will aid in the assessment of the future impact of sea level rise, climate change, and sediment management practices on the region's beaches, tidal wetlands, and submarine resources. Prior work in San Francisco Bay has focused almost exclusively on fine sediment transport (i.e., mud) due to its association with pollutants. However, sand in the San Francisco Bay Coastal system is a critical component for area beaches both inside and outside the bay, protective shoals, tidal wetlands, and aggregate mining. Recent USGS research shows that the San Francisco Bar, a massive sediment body covering over 100 square kilometers, has lost over 90 million cubic meters of sediment, primarily sand, in the last 50 years, and Central San Francisco Bay has lost a comparable volume. With sand dominating the active bed in these regions, understanding the source and potential transport of sand in this system is essential to identifying the reasons for this pattern of massive sediment lost.

The development of the San Francisco Bay Coastal System Project reflects the importance of an integrated, system-wide approach toward understanding sediment transport pathways from the delta mouth to the shelf. No portion of the bay or bay mouth is an isolated system, and in order to understand the evolution, past, present and future, of any region, the processes by which the system interacts must be identified.This work is particularly relevant now, as numerous agencies (e.g. San Francisco Bay Conservation and Development Commission (BCDC), California State Lands, U.S. Army Corps of Engineers, San Francisco District, National Park Service, etc.) are looking to the USGS for science support in developing long-term sediment management strategies in San Francisco Bay. Our work is essential to these agencies seeking to understand the short- and long-term impact of existing or modified sediment management practices on sensitive bay habitats, shoal development leading to navigation hazards, and sediment supply to beaches. The USGS is leading science in this region under this unique project featuring:

• System-wide research integration
• Multiple temporal and spatial scales
• Supporting science for management needs
• Strong academic collaboration
• Diverse, state-of-the-art research tools
• Sand transport focus

Start/End Dates 10/1/2008 - 9/30/2013 Location San Francisco Bay Investigators Barnard, Patrick, Coastal Geologist, Project Chief Erikson, Li, Coastal Engineer Hein, Jim, Geologist Hiett, Janee Jaffe, Bruce, Oceanographer Lacy, Jessie, Oceanographer McGann, Mary, Geologist Rosenbauer, Bob, Geochemist

Fort Point Wayside Poster from National Park Service [larger version]

Objectives

• Quantify sediment transport pathways and mechanisms in the system
• Integrate historical and recent data collection inside and outside the bay
• Assess the influence of anthropogenic activities, past and present
• Develop a sand sediment budget of the bay

Approach

The strength of this project is in the integration of work inside and outside the bay, past and present. We are building from a firm scientific base, but modifying the work to directly address relevant societal needs. Due to our strongly developed research and agency collaboration in the region, spin-up time for the new project is minimal and we can hit the ground running in year 1. The project framework is designed to understand physical processes in numerous portions of the San Francisco Bay Coastal System at a variety of spatial and temporal scales, combining ongoing and new work.

Tasks and SubTasks

• Task 1, 'Synthesis,' ties all the tasks together to present a single, coherent presentation of San Francisco Bay Coastal System sediment transport pathways, historical changes, and anthropogenic impacts.
• Task 2, 'San Francisco Bight Coastal Processes' supports ongoing work along the open-ocean coastline immediately adjacent to the mouth of San Francisco Bay seeking to understand the processes controlling short- and long-term beach evolution, with emphasis on Ocean Beach. Research to date strongly suggests a direct link between bay sediment supply, ebb-tidal delta evolution, and beach response.
• Task 3, 'Crissy Field Coastal Processes,' primarily OFA funded by the National Park Service, represents an important link between bay and open-ocean processes as it is the first sand beach encountered inside the bay. The beach is supplied by littoral drift that moves into the bay, but the shoreline is also strongly shaped by wave and tidal current interaction that result in closure of an inlet leading to Crissy Marsh.
• Task 4, 'Processes and Morphology Near the Mouth of San Francisco Bay,' investigates the evolution of morphology near the entrance to San Francisco Bay over time scales of years to decades. Emphasis is on major sand features and transport pathways. These include the shape and evolution of the Golden Gate sand waves, the massive ebb tidal delta, pocket beaches near the Golden Gate, the Golden Gate narrows, and wind-blown sediment over the San Francisco peninsula.
• Task 5, 'San Francisco Bay Sedimentation and Geomorphic Evolution,' largely OFA-funded, supports ongoing work to quantify historical bay bathymetric changes and synthesize a gravity core data set (over 300 bay-wide), all in an effort to identify and explain system-wide historical and present-day patterns of erosion and deposition.
• Task 6, 'Shoal-Channel Sediment Transport,' is an NSF-funded project to determine the mechanism by which sediment is transferred between shoals and channels in South San Francisco Bay.
• Task 7, 'Persistence of the Cosco Busan Oil Spill in San Francisco Bay,' supports ongoing work to assess the short and long-term impact of this major oil spill on water quality and sensitive habitats in the San Francisco Bay Coastal System.

Products

• SF Bay Coastal System web site
• San Francisco Bight Coastal Processes web site
• Turbid Bay: Sediment in Motion, video: http://walrus.wr.usgs.gov/scivideos.html#turbidbay
• USGS Scientists Investigate Coastal Processes Affecting a Restored Tidal Wetland in the San Francisco Presidio: Sound Waves newsletter article
• Image archive and samples
  
  Publications
• Barnard, P.L., Erikson, L.H. and Hansen, J.E., 2009, Monitoring and modeling shoreline response due to shoreface nourishment on a high-energy coast: Journal of Coastal Research, Special Issue 56, p. 29-33
• Barnard, P.L., Erikson, L.H., Hansen, J.E., and Elias, Edwin, 2009, The Performance of nearshore dredge disposal at Ocean Beach, San Francisco, California, 2005-2007: USGS Open-File Report 2008-1347, 93 p.
• Barnard, P.L., Erikson, L.H. and Kvitek, R.G., 2011, Small-scale sediment transport patterns and bedform morphodynamics: new insights from high resolution multibeam bathymetry. Geo-Marine Letters, Volume 31 (4), p. 227-236, doi:10.1007/s00367-011-0227-1
• Barnard, P.L., Erikson, L.H., Rubin, D.M., Dartnell, P. and Kvitek, R.G., 2012. Analyzing bedforms mapped using multibeam sonar to determine regional bedload sediment transport patterns in the San Francisco Bay coastal system. Sedimentology, In: Li, M.Z., Sherwood, C.R., and Hill, P.R. (Eds.), Sediments, Morphology and Sedimentary Processes on Continental Shelves: Advances in technologies, research and applications. Special Publication 44 of the International Association of Sedimentologists (IAS), p. 273-294
• Barnard, P.L., Hoover, D. and Hansen, J.E., 2011. Nearshore bathymetric evolution on a high-energy beach during the 2009-10 El Niño winter. In: Wang, P., Rosati, J.D. and Roberts, T.M. (Eds.) Coastal Sediments '11, Proceedings of the 7th International Symposium on Coastal Engineering and Science of Coastal Sediment Processes, American Society of Civil Engineers, Miami, FL, p. 1390-1403
• Barnard, Patrick L., and Kvitek, Rikk G., 2010, Anthropogenic influence on recent bathymetric change in west-central San Francisco Bay: San Francisco Estuary and Watershed Science, v. 8, no. 3, 13 p. [http://escholarship.org/uc/item/6k3524hg] [Download pdf (4.1 MB)]
• Barnard, P.L., O'Reilly, B., van Ormondt, M., Elias, E., Ruggiero, P., Erikson, L.H., Hapke, C., Collins, B.D., Guza, R.T., Adams, P.N. and Thomas, J.T., 2009, The framework of a coastal hazards model: a tool for predicting the impact of severe storms: U.S. Geological Survey Open-File Report 2009-1073, 21 pp.
• Brand, A., Lacy, J.R., Hsu, K., Hoover, D., Gladding, S., and M.T. Stacey. 2010. Wind-enhanced resuspension in the shallow waters of South San Francisco Bay: Mechanisms and potential implications for cohesive sediment transport. Journal of Geophysical Research-Oceans 115 (C11024), doi:10.1029/2010JC006172
• Chin, J.L., Woodrow, D.L., McGann, M., Wong. F.L., Fregoso, T., and Jaffe, B. E., 2010, Estuarine Sedimentation in Central San Francisco Bay, California: Chaper I in Chin, J.L., Woodrow, D.L., McGann, Mary, Wong, F.L., Fregoso, Theresa, and Jaffe, B.E., 2010, Estuarine sedimentation, sediment character, and foraminiferal distribution in central San Francisco Bay, California: U.S. Geological Survey Open-File Report 2010-1130, 58 p., data tables, and GIS data., p. 3-13,
• Dallas, Kate L., and Barnard, Patrick L., 2011, Anthropogenic influences on shoreline and nearshore evolution in the San Francisco Bay coastal system: Estuarine, Coastal and Shelf Science, v. 92, no. 1, p. 195-204, doi:10.1016/j.ecss.2010.12.031
• Dallas, K. and Barnard, P.L., 2009, Linking human impacts within an estuary to ebb-tidal delta evolution. Journal of Coastal Research, Special Issue 56, p. 713-716
• Hanes, D. M., 2009, Recent technologies usher in new era of coastal geomorphology research: Eos Trans. AGU, 90(23), 198-199
• Hanes, D.M, Barnard, P.L., Erikson, L.H., Shi, F., Elias, E., Hsu, T.J., Hansen, J.E. and Dallas, K., 2011, Recent scientific advances and their implications for sand management near San Francisco: the influence of the ebb tidal delta. In: Wang, P., Rosati, J.D. and Roberts, T.M. (Eds.) Coastal Sediments '11, Proceedings of the 7th International Symposium on Coastal Engineering and Science of Coastal Sediment Processes, American Society of Civil Engineers, Miami, FL, p. 472-483
• Hansen, Jeff E., and Barnard, Patrick L., 2010, Sub-weekly to interannual variability of a high-energy shoreline: Coastal Engineering, 57(11-12), 959-972. doi:10.1016/j.coastaleng.2010.05.011
• Hansen, J.E. and Barnard, P.L., 2009, The observed relationship between wave conditions and beach response: a tool for coastal management: Journal of Coastal Research, Special Issue 56, p. 1771-1775, http://e-geo.fcsh.unl.pt/ICS2009/_docs/ ICS2009_Volume_II/1771.1775_J.E.Hansen_ICS2009.pdf
• Hansen, J.E., Elias, E., List, J.H. and Barnard, P.L., 2011, A numerical model investigation of the formation and persistence of an erosion hot spot. In: Wang, P., Rosati, J.D. and Roberts, T.M. (Eds.) Coastal Sediments '11, Proceedings of the 7th International Symposium on Coastal Engineering and Science of Coastal Sediment Processes, American Society of Civil Engineers, Miami, FL, p. 1769-1782
• Ji, S., Hanes, D.M., and Shen, H.H., 2009, Comparisons of Physical Experiment and Discrete Element Simulations of Rapidly Sheared Granular Materials in an Annular Shear Cell, Mechanics of Materials: doi:10.1016/j.mechmat.2009.01.029
• Lacy, J.R., and Hoover, D.J., 2011, Wave exposure of Corte Madera Marsh, Marin County, California; a field investigation: US Geological Survey Open-File Report 2011-1183, 28 p.
• McGann, M., 2008, High-resolution foraminiferal, isotopic, and trace element records from Holocene estuarine deposits of San Francisco Bay, California: Journal of Coastal Research, v. 24, no. 5, p. 1092-1109
• McGann, Mary, 2010, Central San Francisco Bay Foraminferal Study: Chaper III in Estuarine sedimentation, sediment character, and foraminiferal distribution in Central San Francisco Bay, California: U.S. Geological Survey Open-File Report 2010-1130, p. 35-58
• Rosenbauer, R.J., Campbell, P.L., Lam, Angela, Lorenson, T.D., Hostettler, F.D., Thomas, Burt, and Wong, F.L., 2010, Reconnaissance of Macondo-1 well oil in sediment and tarballs from the northern Gulf of Mexico shoreline, Texas to Florida: U.S. Geological Survey Open-File Report 2010-1290, 22 p.
• Shi, F., Hanes, D.M., Kirby, J.T., Erikson, L., Barnard, P.L. and Eshleman, J., 2011, Pressure gradient-dominated nearshore circulation on a beach influenced by a large inlet-tidal shoal system. Journal of Geophysical Research-Oceans, Volume 116, C04020, 18 pp., doi:10.1029/2010JC006788
• Sterlini, F., S. J. M. H. Hulscher, and D. M. Hanes, 2009, Simulating and understanding sand wave variation: A case study of the Golden Gate sand waves, J. Geophys. Res., 114, F02007, doi:10.1029/2008JF000999
• Woodrow, D., Chin, J., Wong, F., Fregoso, T., and Jaffe, B., 2010, Gravity cores, radiocarbon dates, and grain-size of surficial sediments, Central San Francisco Bay, California: Chaper II in Estuarine sedimentation, sediment character, and foraminiferal distribution in Central San Francisco Bay, California: U.S. Geological Survey Report Series 2010-1130, p. 14-34
• Yates, M.L., Guza, R.T., O'Reilly, W.C., Hansen, J.E. and Barnard, P.L., 2011, Equilibrium shoreline response of a high wave energy beach. Journal of Geophysical Research-Oceans, Volume 116, C04014, 13 pp., doi:10.1029/2010JC006681
• Yu, X., Hsu, T.J., and Hanes, D.M., 2010, Sediment transport under wave groups: Relative importance between nonlinear wave shape and nonlinear boundary layer streaming, Journal of Geophysical Research: Oceans, 115, C02013, doi:10.1029/2009JC005348